Overview

The flow property on Stripe's Transaction object is now nullable in API version 2026-02-25.preview. Previously, this property always returned a value, with flow.type set to other when no corresponding API object existed for a money movement. Now it returns null in these scenarios.

What Changed

• Transaction.flow is now nullable: The property returns null when there isn't another API object that represents the money movement
• Existing flows unchanged: Money movements like Outbound Payments continue to populate the flow property as before
• Breaking change: Code that assumes flow always has a value may fail

Action Items

Developers integrating with the Stripe API should update their code to properly handle null values for the flow property. This is especially important if your integration directly accesses nested properties like flow.type without null checks.

To upgrade to this version:

1. View your current API version in Stripe Workbench
2. Upgrade to the latest SDK version for your language (Ruby, Python, PHP, Java, Node.js, Go, or .NET)
3. Update webhook endpoints to use the new API version
4. Test your integration thoroughly before deploying to production
5. Use Workbench to perform the upgrade (with 72-hour rollback window available)