🧩 Custom GL Lines Plug-in in NetSuite Explained (With Examples)

Introduction

The Custom GL Lines Plug-in is one of NetSuite’s most powerful accounting customization tools. It allows developers to programmatically add, modify, or remove General Ledger impact lines on transactions such as invoices, journal entries, or vendor bills.

Instead of relying solely on native accounting rules, you can write your own logic to control how transactions post to the GL — making it ideal for custom revenue recognition, allocations, and compliance adjustments.

💡 What Is the Custom GL Lines Plug-in?

The Custom GL Lines Plug-in (CustomGLPlugin type) lets you intercept a transaction after it has generated its GL impact and inject custom lines dynamically before posting.

This enables accounting teams to:

• Add additional expense or revenue lines automatically.
• Split GL impact between departments or subsidiaries.
• Reclassify postings based on business rules.
• Handle region- or tax-specific allocations.

🧠 Key Benefit: It customizes financial impact without changing the core NetSuite accounting engine or transaction forms.

⚙️ Prerequisites

Before using the Custom GL Lines Plug-in:

1. You must have the SuiteScript 2.0 API enabled.
2. Have Administrator or Full Access role.
3. Verify that “Custom GL Lines Plug-in” is enabled under Setup → Company → Enable Features → Accounting → Custom GL Lines Plug-in.
4. Transactions must be GL-impacting (e.g., invoices, vendor bills, journals).

🧱 Plug-in Structure Overview

🧰 Step-by-Step: Creating a Custom GL Lines Plug-in

Step 1: Create the Script File

Go to Customization → Scripting → Scripts → New and choose Custom GL Lines Plug-in.

Step 2: Add SuiteScript 2.0 Implementation

/**
 * @NApiVersion 2.x
 * @NScriptType CustomGLPlugin
 */
define(['N/log'], function (log) {
    function customizeGlImpact(context) {
        try {
            var transactionRecord = context.transactionRecord;
            var type = transactionRecord.type;
            log.debug('Custom GL Plugin', 'Transaction Type: ' + type);

            // Loop through existing GL lines
            var lineCount = context.standardLines.getCount();
            for (var i = 0; i < lineCount; i++) {
                var standardLine = context.standardLines.getLine(i);
                log.debug('Existing Line', standardLine.getAccountId());
            }

            // Example: Add custom freight expense line
            var newLine = context.customLines.addNewLine();
            newLine.setAccountId(1234); // Freight Expense account ID
            newLine.setDebitAmount(50);
            newLine.setMemo('Freight Adjustment');
            newLine.setEntityId(transactionRecord.getValue('entity'));

            log.debug('Custom GL', 'Added freight expense line');
        } catch (e) {
            log.error('Error in customizeGlImpact', e);
        }
    }

    return {
        customizeGlImpact: customizeGlImpact
    };
});

Step 3: Deploy the Plug-in

1. Navigate to Customization → Scripting → Scripts.
2. Edit your Custom GL Script → Deployments tab.
3. Select the transaction type (e.g., Invoice or Vendor Bill).
4. Set Status = Released.

Step 4: Test the Plug-in

• Create a test transaction (e.g., an Invoice).
• Post and check GL Impact → View GL Impact.
• You’ll see the extra GL line added by the script.

🧾 Example Use Cases

🧮 Real-World Scenario: Freight Expense on Vendor Bill

Business Case: The company pays freight costs on vendor bills but wants these costs to post to a separate GL account automatically.

Logic:
If the Vendor Bill includes an item line with Shipping Charge, add an additional GL line debiting the “Freight Expense” account.

Result:
Every time a vendor bill with shipping is posted, an extra freight expense line appears in GL impact—completely automated.

🧰 Debugging and Best Practices

• Always log line IDs and accounts during testing.
• Use sandbox first — the plug-in affects posted entries.
• Don’t use it for non-GL records.
• Avoid double counting: ensure you don’t duplicate standard lines.
• Keep governance simple — these scripts run in posting context only.
• You can create multiple plug-ins for different transaction types.

🧩 Common Errors and Fixes

📊 When to Use Custom GL Plug-ins vs. Workflows

🧠 Pro Tips

• You can combine Custom GL Plug-in + User Event for advanced logic (e.g., based on record status).
• Always keep script deployments specific to transaction types for control.
• For multi-subsidiary setups, test cross-subsidiary posting scenarios.

❓ FAQ

Q1. Can I use Custom GL Plug-in for non-posting transactions?
No — the plug-in only affects transactions that generate GL impact (e.g., Invoice, Bill, Journal).

Q2. Does this replace the standard GL posting?
No, it adds to or modifies the standard impact. The base postings still happen.

Q3. Can multiple Custom GL Plug-ins run on one transaction?
Yes, NetSuite runs them in alphabetical order by script name. Use filters to prevent overlap.

Q4. Where can I find the GL account IDs?
Navigate to Lists → Accounting → Accounts, and hover over the name or view the URL parameter (id=).

🧭 Next Steps & Internal Links

Continue your NetSuite customization journey:

• 👉 Working with Custom Segments
• 👉 SuiteBuilder vs SuiteScript: When to Code & When to Click
• 👉 Custom Buttons and Form Actions in NetSuite

🔑 Summary

The Custom GL Lines Plug-in gives unmatched control over your organization’s accounting logic — letting you tailor financial postings, automate allocations, and ensure compliance directly inside NetSuite.
It bridges the gap between accounting precision and SuiteScript flexibility — making it a must-have tool for every advanced NetSuite developer and controller.