How to use OnlineCheckWriter: A Developers Simple Guide

🚀 Welcome & Quick Start

Welcome to the Online Check Writer API V3! Our API makes it incredibly easy to integrate check writing, payment processing, and banking features into your application. Most integrations take less than 1 hour to complete.

What Can You Do With Our API?

✅ Create and manage bank accounts
✅ Write, print, and mail physical checks
✅ Send checks via email (eCheck)
✅ Process ACH and wire transfers (domestic & international)
✅ Manage virtual bank accounts (Cloud Banking)
✅ Handle cryptocurrency transactions
✅ Create payment links and receive payments
✅ Manage contacts and payees
✅ Generate financial reports and statements

🎯 Quick Start in 3 Steps

Register for a Sandbox account at https://test.onlinecheckwriter.com
Get your API token from the Developer Panel in the left sidebar
Make your first API call to retrieve your user details

📹 Need Help?

Video Tutorial: Watch our API integration video
Live Chat: Click here for immediate help
Skype Support: onlinecheckwriter (Mon-Fri 9am-5pm CST)
Email: support@onlinecheckwriter.com

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🔥 Most Common Use Cases - Complete Guide

These are the three most frequently used API operations. Each section below provides complete, working examples that you can copy and use immediately.

📨 Use Case 1: Check Mailing - Send Physical Checks via USPS

What is Check Mailing?

Check mailing allows you to create a check digitally and have it physically printed and mailed via USPS directly to the recipient. You never have to touch paper or go to the post office.

Prerequisites for Check Mailing:

✅ A verified bank account (bankAccountId) → How to get this
✅ A payee/recipient (payeeId) → How to get this
✅ A created check (checkId) → How to get this
✅ From and To addresses (optional - uses defaults if not provided)

Complete Step-by-Step Process:

Step 1: Create a Bank Account (One-time setup)

POST /bankAccounts
{
  "bankAccounts": [{
    "name": "Business Checking",
    "accountNumber": "1234567890",
    "bankRoutingNumber": "121000358",
    "addressLine1": "123 Business St",
    "city": "San Jose",
    "state": "CA",
    "zip": "95113",
    "bankName": "Chase Bank"
  }]
}

// Response: { "bankAccountId": "bnk_12345" }

Step 2: Create a Payee (The recipient)

POST /payees
{
  "payees": [{
    "name": "John Smith",
    "addressLine1": "789 Main Street",
    "addressLine2": "Apt 4B",
    "city": "Los Angeles",
    "state": "CA",
    "zip": "90001",
    "phone": "555-0123"
  }]
}

// Response: { "payeeId": "pay_67890" }

Step 3: Create the Check

Need these IDs? Get bankAccountId | Get payeeId

POST /checks
{
  "checks": [{
    "bankAccountId": "bnk_12345",  // From Step 1
    "payeeId": "pay_67890",         // From Step 2
    "amount": 500.00,
    "memo": "Payment for Invoice #1234",
    "issueDate": "2024-01-25"
  }]
}

// Response: { "checkId": "chk_99999" }

Step 4: Mail the Check

Need the check ID? Learn how to create checks →

POST /mailchecks
{
  "checkId": "chk_99999",  // From Step 3
  "mailType": 1,            // 1 = First Class (3-5 days)
  "sendDate": "2024-01-26"  // Optional: Schedule for future
}

// Response: { "success": true, "trackingNumber": "XXXXX" }

Mail Type Options:

Mail Type	Description	Delivery Time	Cost
1	First Class Mail	3-5 business days	$1.85
2	First Class with Tracking	3-5 business days	$4.50
3	Express Mail	1-2 business days	$26.35

Complete JavaScript Example for Check Mailing:

async function mailCheckComplete() {
  const API_TOKEN = 'your_token_here';
  const BASE_URL = 'https://test.onlinecheckwriter.com/api/v3';
  
  const headers = {
    'Authorization': `Bearer ${API_TOKEN}`,
    'Content-Type': 'application/json'
  };

  // Step 1: Create bank account (skip if already exists)
  const bankResponse = await fetch(`${BASE_URL}/bankAccounts`, {
    method: 'POST',
    headers: headers,
    body: JSON.stringify({
      bankAccounts: [{
        name: "Business Checking",
        accountNumber: "1234567890",
        bankRoutingNumber: "121000358",
        addressLine1: "123 Business St",
        city: "San Jose",
        state: "CA",
        zip: "95113"
      }]
    })
  });
  const bank = await bankResponse.json();
  const bankAccountId = bank.data.bankAccounts[0].bankAccountId;

  // Step 2: Create payee
  const payeeResponse = await fetch(`${BASE_URL}/payees`, {
    method: 'POST',
    headers: headers,
    body: JSON.stringify({
      payees: [{
        name: "Vendor ABC",
        addressLine1: "456 Vendor Ave",
        city: "Dallas",
        state: "TX",
        zip: "75001"
      }]
    })
  });
  const payee = await payeeResponse.json();
  const payeeId = payee.data.payees[0].payeeId;

  // Step 3: Create check
  const checkResponse = await fetch(`${BASE_URL}/checks`, {
    method: 'POST',
    headers: headers,
    body: JSON.stringify({
      checks: [{
        bankAccountId: bankAccountId,
        payeeId: payeeId,
        amount: 1000.00,
        memo: "Monthly payment"
      }]
    })
  });
  const check = await checkResponse.json();
  const checkId = check.data.checks[0].checkId;

  // Step 4: Mail the check
  const mailResponse = await fetch(`${BASE_URL}/mailchecks`, {
    method: 'POST',
    headers: headers,
    body: JSON.stringify({
      checkId: checkId,
      mailType: 1  // First class mail
    })
  });
  
  const result = await mailResponse.json();
  console.log('Check mailed successfully!', result);
  return result;
}

🖨️ Use Case 2: Check Printing - Generate PDF for Local Printing

What is Check Printing?

Check printing generates a PDF file that you can download and print on your own check stock or blank paper. Perfect for businesses that want to print checks in-house.

Prerequisites for Check Printing:

✅ A verified bank account (bankAccountId) → How to get this
✅ A payee/recipient (payeeId) → How to get this
✅ A created check (checkId) → How to get this

Complete Step-by-Step Process:

Step 1-3: Same as Check Mailing (Create Bank Account, Payee, and Check)

Step 4: Print the Check to PDF

POST /checks/print
{
  "checkId": ["chk_99999"],  // Can print multiple checks at once
  "paperType": 1              // See paper types below
}

// Response: { 
//   "success": true, 
//   "data": { 
//     "url": "https://download-link.com/your-check.pdf" 
//   }
// }

Paper Type Options:

Paper Type	Description	Best For
1	Check on Top	Standard business checks with stub at bottom
2	Check on Middle	Checks with stubs on top and bottom
3	Check on Bottom	Checks with stub at top
4	Three per page	Multiple checks on one page
5	Wallet size	Personal-sized checks
6	Simple print	Plain paper printing (no special stock needed)

Complete JavaScript Example for Check Printing:

async function printCheckComplete() {
  const API_TOKEN = 'your_token_here';
  const BASE_URL = 'https://test.onlinecheckwriter.com/api/v3';
  
  const headers = {
    'Authorization': `Bearer ${API_TOKEN}`,
    'Content-Type': 'application/json'
  };

  // Step 1: Get existing bank account (or create new)
  const banksResponse = await fetch(`${BASE_URL}/bankAccounts`, {
    method: 'GET',
    headers: headers
  });
  const banks = await banksResponse.json();
  const bankAccountId = banks.data.bankAccounts[0].bankAccountId;

  // Step 2: Get existing payee (or create new)
  const payeesResponse = await fetch(`${BASE_URL}/payees`, {
    method: 'GET',
    headers: headers
  });
  const payees = await payeesResponse.json();
  const payeeId = payees.data.payees[0].payeeId;

  // Step 3: Create check with voucher for detailed stub
  const checkResponse = await fetch(`${BASE_URL}/checks`, {
    method: 'POST',
    headers: headers,
    body: JSON.stringify({
      checks: [{
        bankAccountId: bankAccountId,
        payeeId: payeeId,
        amount: 2500.00,
        memo: "Professional Services",
        invoiceNumber: "INV-2024-001",
        voucher: {
          voucherNumber: "V001",
          memo: "January Services",
          date: "2024-01-31",
          voucherItems: [
            {
              name: "Consulting",
              description: "20 hours @ $100",
              quantity: 20,
              unitCost: 100,
              total: 2000
            },
            {
              name: "Travel",
              description: "Expenses",
              quantity: 1,
              unitCost: 500,
              total: 500
            }
          ]
        }
      }]
    })
  });
  const check = await checkResponse.json();
  const checkId = check.data.checks[0].checkId;

  // Step 4: Generate PDF for printing
  const printResponse = await fetch(`${BASE_URL}/checks/print`, {
    method: 'POST',
    headers: headers,
    body: JSON.stringify({
      checkId: [checkId],
      paperType: 1  // Check on top
    })
  });
  
  const result = await printResponse.json();
  console.log('PDF URL:', result.data.url);
  
  // Optional: Download the PDF
  window.open(result.data.url, '_blank');
  
  return result;
}

Bulk Printing Example:

// Print multiple checks at once
POST /checks/print
{
  "checkId": ["chk_111", "chk_222", "chk_333"],
  "paperType": 4  // Three per page
}

// Returns single PDF with all checks

📧 Use Case 3: eCheck (Email Check) - Send Checks Digitally

What is eCheck?

eCheck (electronic check) allows you to send checks digitally via email. The recipient receives a secure PDF of the check that they can print or deposit electronically. It's instant, free, and environmentally friendly.

Prerequisites for eCheck:

✅ A verified bank account (bankAccountId) → How to get this
✅ A payee/recipient (payeeId) → How to get this
✅ A created check (checkId) → How to get this
✅ Recipient's email address

Complete Step-by-Step Process:

Step 1-3: Same as above (Create Bank Account, Payee, and Check)

Step 4: Email the Check

POST /emailchecks
{
  "checkId": "chk_99999",
  "recipientEmail": "recipient@example.com",
  "subject": "Payment for Invoice #1234",
  "message": "Please find attached your payment. Thank you for your services.",
  "ccEmails": ["accounting@company.com", "records@company.com"],
  "sendDate": "2024-01-25"  // Optional: Schedule for later
}

// Response: { 
//   "success": true, 
//   "message": "Check emailed successfully"
// }

eCheck Parameters Explained:

Parameter	Required	Description
`checkId`	Yes	The ID of the check to email
`recipientEmail`	Yes	Primary recipient's email
`subject`	No	Email subject line (default: "Payment from [Your Name]")
`message`	No	Email body message
`ccEmails`	No	Array of CC recipients
`sendDate`	No	Schedule for future delivery (YYYY-MM-DD)

Complete JavaScript Example for eCheck:

async function sendECheckComplete() {
  const API_TOKEN = 'your_token_here';
  const BASE_URL = 'https://test.onlinecheckwriter.com/api/v3';
  
  const headers = {
    'Authorization': `Bearer ${API_TOKEN}`,
    'Content-Type': 'application/json'
  };

  // Step 1: Create or get bank account
  const banksResponse = await fetch(`${BASE_URL}/bankAccounts`, {
    method: 'GET',
    headers: headers
  });
  const banks = await banksResponse.json();
  let bankAccountId;
  
  if (banks.data.bankAccounts.length === 0) {
    // Create new bank account
    const newBankResponse = await fetch(`${BASE_URL}/bankAccounts`, {
      method: 'POST',
      headers: headers,
      body: JSON.stringify({
        bankAccounts: [{
          name: "Business Checking",
          accountNumber: "9876543210",
          bankRoutingNumber: "121000358",
          addressLine1: "456 Corporate Blvd",
          city: "San Francisco",
          state: "CA",
          zip: "94105"
        }]
      })
    });
    const newBank = await newBankResponse.json();
    bankAccountId = newBank.data.bankAccounts[0].bankAccountId;
  } else {
    bankAccountId = banks.data.bankAccounts[0].bankAccountId;
  }

  // Step 2: Create payee with email
  const payeeResponse = await fetch(`${BASE_URL}/payees`, {
    method: 'POST',
    headers: headers,
    body: JSON.stringify({
      payees: [{
        name: "Digital Vendor LLC",
        email: "vendor@digitalvendor.com",
        addressLine1: "789 Online Ave",
        city: "Austin",
        state: "TX",
        zip: "78701",
        phone: "555-9999"
      }]
    })
  });
  const payee = await payeeResponse.json();
  const payeeId = payee.data.payees[0].payeeId;

  // Step 3: Create check with attachment option
  const checkResponse = await fetch(`${BASE_URL}/checks`, {
    method: 'POST',
    headers: headers,
    body: JSON.stringify({
      checks: [{
        bankAccountId: bankAccountId,
        payeeId: payeeId,
        amount: 750.00,
        memo: "Website development - Phase 1",
        invoiceNumber: "WEB-2024-001",
        note: "Internal: Q1 web project"
      }]
    })
  });
  const check = await checkResponse.json();
  const checkId = check.data.checks[0].checkId;

  // Step 4: Email the check
  const emailResponse = await fetch(`${BASE_URL}/emailchecks`, {
    method: 'POST',
    headers: headers,
    body: JSON.stringify({
      checkId: checkId,
      recipientEmail: "vendor@digitalvendor.com",
      subject: "Payment for Website Development - Invoice WEB-2024-001",
      message: `Dear Digital Vendor LLC,

Please find attached the payment for Phase 1 of the website development project.
The check can be printed or deposited electronically.

Amount: $750.00
Invoice: WEB-2024-001

Thank you for your excellent work!

Best regards,
Accounts Payable`,
      ccEmails: ["accounting@mycompany.com", "projectmanager@mycompany.com"],
      sendDate: "2024-01-25"
    })
  });
  
  const result = await emailResponse.json();
  console.log('eCheck sent successfully!', result);
  return result;
}

Advanced eCheck Example with Attachment:

// First, add an attachment to the check
POST /checks/{checkId}/attachments
// Upload invoice or supporting document

// Then email the check with attachment
POST /emailchecks
{
  "checkId": "chk_99999",
  "recipientEmail": "vendor@example.com",
  "subject": "Payment with Invoice Attached",
  "message": "Payment and invoice documentation attached."
}

🎯 Quick Decision Guide: Which Method Should You Use?

Scenario	Best Method	Why
Recipient prefers physical checks	Check Mailing	Arrives via USPS, no action needed from you
You want to print checks in-office	Check Printing	Full control, immediate printing
Need instant delivery	eCheck	Arrives in seconds via email
Saving on postage	eCheck	No mailing costs
Bulk payments to multiple vendors	Check Printing	Print all at once on multi-check paper
Remote/international recipients	eCheck	No geographical limitations

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🏁 Getting Started

Step 1: Create Your Account

For Testing (Sandbox)

Go to https://test.onlinecheckwriter.com
Register for a free sandbox account
Login and navigate to the Developer Panel

For Production (Live)

Go to https://app.onlinecheckwriter.com
Register for a live account
Complete account verification
Contact support@onlinecheckwriter.com to enable API access

Step 2: Get Your API Token

Login to your account
Click on "Developer Panel" in the left sidebar
Copy your API token (keep it secure!)

Step 3: Test Your Connection

Make a simple GET request to verify your setup:

curl --request GET \
  --url 'https://test.onlinecheckwriter.com/api/v3/me' \
  --header 'Authorization: Bearer YOUR_API_TOKEN' \
  --header 'Accept: application/json'

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🔴 IMPORTANT: API Prerequisites & Dependencies

⚠️ READ THIS FIRST - Understanding API Dependencies

Many API endpoints require IDs from other resources. You CANNOT create a check without first having a bank account and payee. This section shows you exactly what you need and in what order.

🔄 API Dependency Quick Reference Table

What You Want To Do	Required IDs/Data	How To Get Them (In Order)
Create a Check	`bankAccountId` →, `payeeId` →	1. POST /bankAccounts OR GET /bankAccounts 2. POST /payees OR GET /payees 3. Then POST /checks
Print a Check	`checkId` →	1. Create check first (POST /checks) 2. Use checkId from response 3. POST /checks/print
Mail a Check	`checkId` →, `fromAddressId`, `toAddressId`	1. Create check (POST /checks) 2. Create addresses (POST /customFromAddress, POST /customToAddress) 3. POST /mailchecks
Email a Check	`checkId` →	1. Create check (POST /checks) 2. POST /emailchecks
Add Signature	`bankAccountId` →	1. Create bank account (POST /bankAccounts) 2. POST /bankAccounts/{id}/signatures
Create Check with Category	`bankAccountId` →, `payeeId` →, `categoryId` →	1. Create bank account 2. Create payee 3. Create category (POST /categories) 4. POST /checks
Add Attachment to Check	`checkId` →	1. Create check first 2. POST /checks/{checkId}/attachments
Cloud Bank ACH Payment	`accountId` →, `contactId`	1. Create cloud bank account 2. Create contact 3. POST /cloud-bank/send-payment/ach
Fund Cloud Bank Account	`accountId` →, `sourceBankAccountId` →	1. Create cloud bank account 2. Have verified bank account 3. POST /cloud-bank/account/{id}/fund

📋 First-Time Setup Checklist (Do These First!)

Follow this EXACT order when setting up your integration for the first time:

Step 1: Get Your User Information

GET /me
# Save your userId and account details

Step 2: Create a Bank Account

POST /bankAccounts
{
  "bankAccounts": [{
    "name": "My Business Account",
    "accountNumber": "1234567890",
    "bankRoutingNumber": "121000358",
    # ... other required fields
  }]
}
# SAVE THE RESPONSE: bankAccountId = "bnk_xxxxx"

Step 3: Add Signature (Optional but Recommended)

POST /bankAccounts/{bankAccountId}/signatures
# Upload signature image file

Step 4: Create Payees (Recipients)

POST /payees
{
  "payees": [{
    "name": "John Smith",
    "addressLine1": "123 Main St",
    # ... other fields
  }]
}
# SAVE THE RESPONSE: payeeId = "pay_xxxxx"

Step 5: Create Categories (Optional)

POST /categories
{
  "categories": [{
    "name": "Office Supplies"
  }]
}
# SAVE THE RESPONSE: categoryId = "cat_xxxxx"

Step 6: NOW You Can Create Checks!

Need these IDs? Get bankAccountId | Get payeeId | Get categoryId

POST /checks
{
  "checks": [{
    "bankAccountId": "bnk_xxxxx",  # From Step 2
    "payeeId": "pay_xxxxx",        # From Step 4
    "categoryId": "cat_xxxxx",     # From Step 5 (optional)
    "amount": 100.00,
    "memo": "Payment"
  }]
}
# SAVE THE RESPONSE: checkId = "chk_xxxxx"

🔍 How to Find Existing IDs

If you already have resources created, here's how to retrieve their IDs:

Get All Bank Account IDs:

→ Jump to Bank Accounts section for full details

GET /bankAccounts

# Response will include:
{
  "data": {
    "bankAccounts": [
      {
        "bankAccountId": "bnk_xxxxx",  # <-- Use this ID
        "name": "Business Checking",
        "isVerified": true              # <-- Check verification status
      }
    ]
  }
}

Get All Payee IDs:

→ Jump to Payees section for full details

GET /payees

# Response will include:
{
  "data": {
    "payees": [
      {
        "payeeId": "pay_xxxxx",  # <-- Use this ID
        "name": "John Smith"
      }
    ]
  }
}

Get All Check IDs:

→ Jump to Checks section for full details

GET /checks

# Response will include:
{
  "data": {
    "checks": [
      {
        "checkId": "chk_xxxxx",  # <-- Use this ID
        "status": 0,              # <-- Check status (0 = new)
        "amount": "100.00"
      }
    ]
  }
}

Get All Category IDs:

→ Jump to Categories section for full details

GET /categories

# Response will include:
{
  "data": {
    "categories": [
      {
        "categoryId": "cat_xxxxx",  # <-- Use this ID
        "name": "Office Supplies"
      }
    ]
  }
}

❌ Common Mistakes to Avoid

DON'T try to create a check without first having:
- A valid bankAccountId
- A valid payeeId (unless using noPayee: true)
DON'T try to print/mail/email a check without first creating it
DON'T try to add attachments/signatures without the parent resource
DON'T assume IDs from sandbox will work in production

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🔧 Environment Setup

API Endpoints

Environment	Base URL
Sandbox (Testing)	`https://test.onlinecheckwriter.com/api/v3`
Production (Live)	`https://app.onlinecheckwriter.com/api/v3`

Environment Variables

Set up these variables in your application:

# Required
BASE_URL=https://test.onlinecheckwriter.com/api/v3
AUTH_TOKEN=your_api_token_here

# Optional (will be populated as you create resources)
BANK_ACCOUNT_ID=
PAYEE_ID=
CATEGORY_ID=
CHECK_ID=
CUSTOM_FROM_ADDRESS_ID=
CUSTOM_TO_ADDRESS_ID=
VOUCHER_ID=
CUSTOMER_ID=
CUSTOMER_BANK_ACCOUNT_ID=

HTTP Methods

Method	Description	Usage
GET	Retrieve resources	Fetching data
POST	Create resources	Creating new records
PUT	Update resources	Modifying existing records
DELETE	Delete resources	Removing records

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🔐 Authentication

All API requests require Bearer token authentication.

How to Authenticate

Include your API token in the Authorization header of every request:

Authorization: Bearer YOUR_API_TOKEN

Required Headers

Every request should include these headers:

Authorization: Bearer YOUR_API_TOKEN
Content-Type: application/json
Accept: application/json

Example Authenticated Request

curl --request GET \
  --url 'https://test.onlinecheckwriter.com/api/v3/bankAccounts' \
  --header 'Authorization: Bearer YOUR_API_TOKEN' \
  --header 'Content-Type: application/json' \
  --header 'Accept: application/json'

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📖 API Reference

User Management

Get User Details

Retrieve information about the authenticated user.

Endpoint: GET /me

Request Example:

curl --request GET \
  --url '{{BASE_URL}}/me' \
  --header 'Authorization: Bearer {{AUTH_TOKEN}}'

Success Response (200 OK):

{
  "success": true,
  "data": {
    "userId": "usr_xxxxx",
    "email": "user@example.com",
    "name": "John Doe",
    "company": "Example Corp",
    "accountType": "business"
  }
}

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Bank Accounts

Create Bank Accounts

Create multiple bank accounts in a single request.

Endpoint: POST /bankAccounts

Request Body:

Need help finding IDs for checks? After creating a bank account, save the bankAccountId from the response to use when creating checks.

{
  "bankAccounts": [
    {
      "name": "Business Checking",
      "nickName": "Main Account",
      "accountNumber": "1234567890",
      "addressLine1": "123 Business St",
      "addressLine2": "Suite 100",
      "phone": "555-0100",
      "city": "San Jose",
      "state": "CA",
      "zip": "95113",
      "bankName": "Chase Bank",
      "bankRoutingNumber": "121000358",
      "bankAddress1": "456 Bank Ave",
      "bankCity": "Dallas",
      "bankState": "TX",
      "bankZip": "75001"
    }
  ]
}

Parameters:

Parameter	Type	Required	Description
name	String	✅ Yes	Bank account name (max 100 chars)
nickName	String	No	Nickname for the account (max 100 chars)
accountNumber	String	✅ Yes	Account number (max 20 chars)
addressLine1	String	✅ Yes	Primary address (max 180 chars)
addressLine2	String	No	Secondary address (max 180 chars)
phone	String	No	Phone number (max 15 chars)
city	String	✅ Yes	City name
state	String	✅ Yes	State abbreviation (e.g., "CA")
zip	String	✅ Yes	Valid ZIP code
bankName	String	No	Name of the bank (max 100 chars)
bankRoutingNumber	String	✅ Yes	9-digit US routing number
bankAddress1	String	No	Bank address line 1 (max 180 chars)
bankCity	String	No	Bank city
bankState	String	No	Bank state
bankZip	String	No	Bank ZIP code

Success Response (201 Created):

{
  "success": true,
  "message": "Successfully created",
  "data": {
    "bankAccounts": [
      {
        "bankAccountId": "bnk_xxxxx",
        "name": "Business Checking",
        "isVerified": false
      }
    ]
  }
}

Retrieve All Bank Accounts

List all bank accounts with optional filtering.

Endpoint: GET /bankAccounts

Retrieve Single Bank Account

Get details of a specific bank account.

Endpoint: GET /bankAccounts/{bankAccountId}

Update Bank Account

Modify an existing bank account.

Endpoint: PUT /bankAccounts/{bankAccountId}

Delete Bank Account

Remove a bank account from your account.

Endpoint: DELETE /bankAccounts/{bankAccountId}

Add Signature to Bank Account

Upload a signature image for check signing. Need a bankAccountId? Create or retrieve one first

Endpoint: POST /bankAccounts/{bankAccountId}/signatures

Add Logo to Bank Account

Upload a logo for check customization.

Endpoint: POST /bankAccounts/{bankAccountId}/logos

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Checks

Create Checks

Create one or multiple checks in a single request.

Endpoint: POST /checks

Request Body:

Need help finding required IDs?

bankAccountId - Get from Bank Accounts →
payeeId - Get from Payees →
categoryId (optional) - Get from Categories →

{
  "checks": [
    {
      "bankAccountId": "yd6LeMYmdQeE8Dx",  // Required - from Bank Accounts
      "payeeId": "Xw2lx48MdGMzWyD",        // Required - from Payees
      "categoryId": "MLbz3Aj3ReVw6Ev",     // Optional - from Categories
      "serialNumber": "1001",
      "issueDate": "2024-01-25",
      "amount": 100.00,
      "memo": "Invoice Payment #1234",
      "note": "Internal reference note",
      "accountNumber": "458756",
      "invoiceNumber": "INV-2024-001",
      "noSign": false,
      "noAmount": false,
      "noDate": false,
      "noPayee": false,
      "voucher": {
        "voucherNumber": "1000",
        "memo": "Monthly Services",
        "date": "2024-01-20",
        "voucherItems": [
          {
            "invoiceNumber": "858",
            "name": "Consulting Services",
            "description": "January 2024 consulting",
            "quantity": 10,
            "unitCost": 50,
            "total": 500
          }
        ]
      }
    }
  ]
}

Check Status Codes

Status	Code	Description
New	0	Newly created check
Printed	1	Check has been printed
Void	2	Check has been voided
Mailed	7	Check has been mailed
Refunded	11	Check mailing refunded
E-Mailed	12	Check sent via email
E-Printed	14	Check printed electronically
DD	300-306	Direct Deposit statuses

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Payees

Create Payees

Add recipients for checks and payments. Save the payeeId from the response to use when creating checks.

Endpoint: POST /payees

Request Body:

{
  "payees": [
    {
      "name": "John Smith",
      "nickName": "Contractor",
      "addressLine1": "789 Main St",
      "addressLine2": "Apt 4B",
      "city": "Los Angeles",
      "state": "CA",
      "zip": "90001",
      "phone": "555-0123",
      "email": "john@example.com"
    }
  ]
}

Retrieve All Payees

Endpoint: GET /payees

Update Payee

Endpoint: PUT /payees/{payeeId}

Delete Payee

Endpoint: DELETE /payees/{payeeId}

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Mail Options

Mail a Check

Send a physical check via USPS. Need a checkId? Create a check first

Endpoint: POST /mailchecks

Request Body:

{
  "checkId": "chk_xxxxx",
  "mailType": 1,
  "fromAddressId": "adr_xxxxx",
  "toAddressId": "adr_yyyyy",
  "sendDate": "2024-01-30"
}

Email a Check

Send a check digitally via email. Need a checkId? Create a check first

Endpoint: POST /emailchecks

Request Body:

{
  "checkId": "chk_xxxxx",
  "recipientEmail": "recipient@example.com",
  "subject": "Payment for Invoice #1234",
  "message": "Please find attached your payment.",
  "ccEmails": ["accounting@example.com"],
  "sendDate": "2024-01-25"
}

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Cloud Banking

Cloud Banking provides virtual bank accounts with full transaction capabilities.

Get Cloud Bank Accounts

Endpoint: GET /cloud-bank/account

Create Cloud Bank Account

Endpoint: POST /cloud-bank/account

Send ACH Payment

Need IDs? Get accountId from Cloud Bank Accounts, create contactId with POST /cloud-bank/contact

Endpoint: POST /cloud-bank/send-payment/ach

Send Wire Transfer (Domestic)

Endpoint: POST /cloud-bank/send-payment/wire

Send International Wire

Endpoint: POST /cloud-bank/send-payment/international-wire

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Additional Features

Payment Links

Create links for customers to pay you.

Endpoint: POST /payment-links

Cryptocurrency Wallets

Manage crypto transactions.

Get Wallets: GET /cloud-bank/crypto/wallet

Activate Wallet: POST /cloud-bank/crypto/wallet

Gift Cards

Create Gift Card: POST /gift-cards

Check Balance: GET /gift-cards/{cardId}/balance

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📊 Complete Workflow Examples

Real-World Scenario 1: Monthly Vendor Payments

Goal: Pay multiple vendors at the end of each month

// Complete workflow with all dependencies
async function processMonthlyVendorPayments() {
  // Step 1: Get your bank account (or create if first time)
  let bankAccountId;
  const bankAccounts = await api.get('/bankAccounts');

  if (bankAccounts.data.bankAccounts.length === 0) {
    // First time - create bank account
    const newBank = await api.post('/bankAccounts', {
      bankAccounts: [{
        name: "Business Checking",
        accountNumber: "1234567890",
        bankRoutingNumber: "121000358",
        addressLine1: "123 Business St",
        city: "San Jose",
        state: "CA",
        zip: "95113"
      }]
    });
    bankAccountId = newBank.data.bankAccounts[0].bankAccountId;
  } else {
    bankAccountId = bankAccounts.data.bankAccounts[0].bankAccountId;
  }

  // Step 2: Get or create vendors (payees)
  const vendors = [
    { name: "ABC Supplies", amount: 1500.00, invoice: "INV-001" },
    { name: "XYZ Services", amount: 2500.00, invoice: "INV-002" }
  ];

  const payeeIds = {};
  const existingPayees = await api.get('/payees');

  for (const vendor of vendors) {
    const existing = existingPayees.data.payees.find(p => p.name === vendor.name);
    if (existing) {
      payeeIds[vendor.name] = existing.payeeId;
    } else {
      const newPayee = await api.post('/payees', {
        payees: [{
          name: vendor.name,
          addressLine1: "Vendor Address",
          city: "City",
          state: "CA",
          zip: "90001"
        }]
      });
      payeeIds[vendor.name] = newPayee.data.payees[0].payeeId;
    }
  }

  // Step 3: Create all checks
  const checksToCreate = vendors.map(vendor => ({
    bankAccountId: bankAccountId,
    payeeId: payeeIds[vendor.name],
    amount: vendor.amount,
    memo: `Payment for ${vendor.invoice}`,
    invoiceNumber: vendor.invoice
  }));

  const checksResponse = await api.post('/checks', {
    checks: checksToCreate
  });

  // Step 4: Process each check (mail or email)
  for (const check of checksResponse.data.checks) {
    // Mail the check
    await api.post('/mailchecks', {
      checkId: check.checkId,
      mailType: 1  // First class mail
    });
  }

  return checksResponse.data.checks;
}

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📊 Response Formats

Success Response Structure

All successful API calls return this format:

{
  "success": true,
  "message": "Operation completed successfully",
  "data": {
    // Response data here
  }
}

Pagination Response

For list endpoints:

{
  "success": true,
  "data": {
    "meta": {
      "total": 100,
      "currentPage": 1,
      "perPage": 10
    },
    "items": [
      // Array of items
    ]
  }
}

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❌ Error Handling

Error Response Structure

{
  "success": false,
  "errorMsg": "Human-readable error message"
}

HTTP Status Codes

Status Code	Meaning	Description
200	OK	Request successful
201	Created	Resource created successfully
400	Bad Request	Invalid request parameters
401	Unauthorized	Invalid or missing API token
403	Forbidden	Access denied to resource
404	Not Found	Resource not found
422	Unprocessable Entity	Validation errors
429	Too Many Requests	Rate limit exceeded
500	Server Error	Internal server error

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💻 Code Examples

JavaScript/Node.js Example

const axios = require('axios');

// Configuration
const API_TOKEN = 'your_api_token_here';
const BASE_URL = 'https://test.onlinecheckwriter.com/api/v3';

// Create axios instance with default config
const api = axios.create({
  baseURL: BASE_URL,
  headers: {
    'Authorization': `Bearer ${API_TOKEN}`,
    'Content-Type': 'application/json',
    'Accept': 'application/json'
  }
});

// Example: Create a check
async function createCheck() {
  try {
    const response = await api.post('/checks', {
      checks: [{
        bankAccountId: 'bnk_xxxxx',
        payeeId: 'pay_xxxxx',
        amount: 100.00,
        memo: 'Payment for services',
        issueDate: '2024-01-25'
      }]
    });

    console.log('Check created:', response.data);
    return response.data.data.checks[0].checkId;
  } catch (error) {
    console.error('Error creating check:', error.response.data);
  }
}

// Example: Print the check
async function printCheck(checkId) {
  try {
    const response = await api.post('/checks/print', {
      paperType: 1,
      checkId: [checkId]
    });

    console.log('PDF URL:', response.data.data.url);
  } catch (error) {
    console.error('Error printing check:', error.response.data);
  }
}

// Run the examples
(async () => {
  const checkId = await createCheck();
  if (checkId) {
    await printCheck(checkId);
  }
})();

Python Example

import requests
import json

# Configuration
API_TOKEN = 'your_api_token_here'
BASE_URL = 'https://test.onlinecheckwriter.com/api/v3'

# Headers for all requests
headers = {
    'Authorization': f'Bearer {API_TOKEN}',
    'Content-Type': 'application/json',
    'Accept': 'application/json'
}

# Create a check
def create_check():
    url = f'{BASE_URL}/checks'

    payload = {
        'checks': [{
            'bankAccountId': 'bnk_xxxxx',
            'payeeId': 'pay_xxxxx',
            'amount': 100.00,
            'memo': 'Payment for services',
            'issueDate': '2024-01-25'
        }]
    }

    response = requests.post(url, headers=headers, json=payload)

    if response.status_code == 201:
        data = response.json()
        check_id = data['data']['checks'][0]['checkId']
        print(f'Check created: {check_id}')
        return check_id
    else:
        print(f'Error: {response.json()}')
        return None

# Print the check
def print_check(check_id):
    url = f'{BASE_URL}/checks/print'

    payload = {
        'paperType': 1,
        'checkId': [check_id]
    }

    response = requests.post(url, headers=headers, json=payload)

    if response.status_code == 200:
        data = response.json()
        print(f'PDF URL: {data["data"]["url"]}')
    else:
        print(f'Error: {response.json()}')

# Run the example
if __name__ == '__main__':
    check_id = create_check()
    if check_id:
        print_check(check_id)

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🔍 Testing Best Practices

Sandbox Testing Guidelines

Use Test Data
- Use fake/test account numbers
- Use test routing number: 121000358
- Use amounts under $100 for testing
Test All Scenarios
- Successful transactions
- Failed transactions
- Edge cases (zero amounts, future dates)
Verify Before Production
- Test all endpoints in sandbox
- Verify response handling
- Test error scenarios

Moving to Production

Get Production Access
- Contact support@onlinecheckwriter.com
- Complete verification process
- Receive production API token
Update Configuration
- Change BASE_URL to production
- Update API token
- Verify bank accounts
Start Small
- Begin with small transactions
- Monitor responses closely
- Scale gradually

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📞 Support & Resources

Get Help

Immediate Support:

Live Chat: https://onlinecheckwriter.com/contact/
Skype: onlinecheckwriter (Mon-Fri 9am-5pm CST)
Email: support@onlinecheckwriter.com

Resources:

Video Tutorial: API Integration Video
Sandbox Environment: https://test.onlinecheckwriter.com
Production Environment: https://app.onlinecheckwriter.com

Common Issues & Solutions

Issue: 401 Unauthorized

Solution: Verify your API token is correct and active

Issue: 422 Validation Error

Solution: Check required fields and data formats

Issue: Rate Limit Exceeded

Solution: Implement request throttling, contact support for limit increase

Issue: Check Creation Fails

Solution: Ensure bank account is verified (for production)

FAQ

Q: How long does integration take?
A: Most developers complete integration in under 1 hour.

Q: Can I test without real bank accounts?
A: Yes! Use the sandbox environment with test data.

Q: What's the rate limit?
A: Default is 60 requests per minute. Contact support for increases.

Q: Is the API PCI compliant?
A: Yes, our API is fully PCI compliant and secure.

🎉 Conclusion

Congratulations! You now have all the information needed to integrate with the Online Check Writer API V3.

Remember:

Start with the sandbox environment
Test thoroughly before going live
Don't hesitate to contact support
Integration typically takes less than 1 hour

Happy coding! 🚀

Last Updated: January 2024
API Version: V3
Documentation Version: 1.0

OnlineCheckWriter.com - Powered by Zil Money Corporation
Changing the way small and medium businesses transact.

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How to OnlineCheckWriter: A Developers Simple Guide

How to use OnlineCheckWriter: A Developers Simple Guide

📚 Online Check Writer API V3 - Complete Integration Guide for Beginners

📖 Table of Contents

🚀 Welcome & Quick Start

What Can You Do With Our API?

🎯 Quick Start in 3 Steps

📹 Need Help?

🔥 Most Common Use Cases - Complete Guide

📨 Use Case 1: Check Mailing - Send Physical Checks via USPS

What is Check Mailing?

Prerequisites for Check Mailing:

Complete Step-by-Step Process:

Mail Type Options:

Complete JavaScript Example for Check Mailing:

🖨️ Use Case 2: Check Printing - Generate PDF for Local Printing

What is Check Printing?

Prerequisites for Check Printing:

Complete Step-by-Step Process:

Paper Type Options:

Complete JavaScript Example for Check Printing:

Bulk Printing Example:

📧 Use Case 3: eCheck (Email Check) - Send Checks Digitally

What is eCheck?

Prerequisites for eCheck:

Complete Step-by-Step Process:

eCheck Parameters Explained:

Complete JavaScript Example for eCheck:

Advanced eCheck Example with Attachment:

🎯 Quick Decision Guide: Which Method Should You Use?

🏁 Getting Started

Step 1: Create Your Account

For Testing (Sandbox)

For Production (Live)

Step 2: Get Your API Token

Step 3: Test Your Connection

🔴 IMPORTANT: API Prerequisites & Dependencies

⚠️ READ THIS FIRST - Understanding API Dependencies

🔄 API Dependency Quick Reference Table

📋 First-Time Setup Checklist (Do These First!)

Step 1: Get Your User Information

Step 2: Create a Bank Account

Step 3: Add Signature (Optional but Recommended)

Step 4: Create Payees (Recipients)

Step 5: Create Categories (Optional)

Step 6: NOW You Can Create Checks!

🔍 How to Find Existing IDs

Get All Bank Account IDs:

Get All Payee IDs:

Get All Check IDs:

Get All Category IDs:

❌ Common Mistakes to Avoid

🔧 Environment Setup

API Endpoints

Environment Variables

HTTP Methods

🔐 Authentication

How to Authenticate

Required Headers

Example Authenticated Request

📖 API Reference

User Management

Get User Details

Bank Accounts

Create Bank Accounts

Retrieve All Bank Accounts

Retrieve Single Bank Account

Update Bank Account

Delete Bank Account

Add Signature to Bank Account

Add Logo to Bank Account

Checks

Create Checks

Check Status Codes

Payees

Create Payees

Retrieve All Payees

Update Payee

Delete Payee

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