Common Mistakes in SuiteScript (and How to Avoid Them)

Introduction

SuiteScript is a powerful tool that allows developers to customize and extend NetSuite’s capabilities. However, if you’re new to SuiteScript (especially 2.0 or 2.1), it’s easy to run into common mistakes that can cause unexpected behavior, performance issues, or even break your customizations.

In this post, we'll cover the most frequent mistakes developers make when writing SuiteScript—and more importantly, how you can avoid them to build better, cleaner, and more reliable code.

1. Forgetting to Check context.type in User Event Scripts

The Mistake

Many developers forget to check the context.type when writing beforeSubmit or afterSubmit scripts. This leads to scripts executing even when they shouldn't like during edits or deletions.

function beforeSubmit(context) {
    var record = context.newRecord;
    // logic here runs on all operations (create, edit, delete)
}

The Fix

Always wrap your logic with a check:

if (context.type === context.UserEventType.CREATE) {
  // logic only for new records
}

2. Using getText Instead of getValue (or Vice Versa)

The Mistake

Developers often confuse getValue() and getText(). This results in using the wrong data type in their logic or saving incorrect values.

The Fix

• Use getValue() for internal values (IDs, numbers, booleans).

• Use getText() when you need the human-readable version.

3. Not Handling Null or Undefined Values

The Mistake

Accessing fields without checking if they exist can cause scripts to throw errors, especially on optional fields.

var val = record.getValue({ fieldId: 'custom_field' });  
// May return null or undefined

The Fix

Always check if the value exists:

if (val !== null && val !== '') {
  // safe to use
}

4. Too Many record.load() Calls

The Mistake

Unnecessarily loading or saving records inside a loop (or within User Event scripts) can slow down performance and hit governance limits.

The Fix

• Use context.newRecord when available.

• If you must load records, try batching logic or using lookupFields().

5. Not Using Logs Effectively

The Mistake

Writing scripts without enough log.debug() statements make it hard to debug issues later.

The Fix

Use logs to track variable values and key execution points:

log.debug('Invoice Date:', invoiceDate);
log.debug('Due Date Calculated:', dueDate);

Set the log level to “Debug” in your script deployment to see them. Update the log level like audit, if you want to filter logs in execution logs.

6. Ignoring Modularity and Code Structure in 2.x

The Mistake

Copy-pasting long procedural scripts without using reusable helper functions or separate modules.

The Fix

Break code into smaller functions. Use additional custom modules when logic gets too long.

7. Missing Permissions for Script Execution

The Mistake

Your script works in Sandbox, but not in Production? Often, the issue is missing role permissions.

The Fix

Ensure the role assigned to the script execution user has:

• Script: Full

• Script Deployment: Full

• File Cabinet: Full (if accessing files)

• Plus permissions related to the record the script is acting on

8. Not Testing in Sandbox First

The Mistake

Deploying scripts directly in Production without full testing.

The Fix

• Always test in Sandbox or Release Preview.

• Use the Testing status during initial deployment.

• Add logs and comments during testing, then clean up before Production.

9. Ignoring Governance Limits

The Mistake

Scripts break when scaled because developers forget NetSuite enforces script governance usage (usage units).

The Fix

• Use runtime.getCurrentScript().getRemainingUsage() to check usage.

• Use Map/Reduce or Scheduled Scripts for processing large data.

10. Hardcoding Internal IDs

The Mistake

Using hardcoded values like internal IDs in scripts can break things if IDs change or vary across environments.

The Fix

• Use runtime.envType to differentiate environments.

• Prefer script parameters, custom labels, or configuration records.

Bonus Tip: Always Read the SuiteScript API Docs

The SuiteScript 2.x API documentation is your best friend. It’s up-to-date, searchable, and full of examples. Bookmark it.

Conclusion

Mistakes in SuiteScript are common—especially when you’re starting out. But with awareness and a few best practices, you can avoid these pitfalls and build reliable customizations in NetSuite. I will talk more about other mistakes we make during our development in Netsuite.

Check out - Getting Started with SuiteScript 2.0: Your First Script

Have a question about a SuiteScript issue? Drop it in the comments, and I’ll help you debug it.