HubSpot Developer Changelog (2)

New Size Limits for App Events and App Event Properties

Announced: March 18, 2025

We have revised the size restrictions for App Events, also referred to as Timeline Events or Integration Events, to ensure seamless integration within the UnifiedEvents ecosystem.

Changes to list membership actions in the v4 Automation API

Announced: March 12, 2025

What's changing? The “alter list membership” action ("actionTypeId": "0-13") is being split into two distinct actions: “add to list” (actionTypeId 0-63809083) and “remove from list” (actionTypeId 0-63863438). These new separate action types will be...

February 2025 Rollup

Announced: February 28, 2025

HubSpot's February 2025 developer updates include a new Tax Rates API for managing commerce tax rates, updates to the Exports API for better control and efficiency, visibility of unpublished custom workflow actions in developer test accounts, a new...

Removing deprecated event types from the Event Analytics API

Announced: February 26, 2025

Beginning on March 5, 2025, deprecated event types will no longer be returned from the endpoint to get all event types: GET /events/v3/events/event-types

Breaking Change for v3 Lists API Beta

Live: April 28, 2025

The v3 Lists API beta currently accepts both integers and strings for the ID of public folders used for list segmentation and returns the ID as an integer. We will be updating the IDs to use only strings in order to conform to the HubSpot...

Final Reminder: Sunset of v2 Owners API

Live: March 24, 2025

The v2 Owners API will officially be sunset on March 24th, 2025, with no further extensions. After this date, all v2 Owners API endpoints will be fully sunset and return a 404 error response. This marks the final stage of our transition to the more...

Marketing Email API: v3 released to general availability and upcoming sunset for v1

Live: October 1, 2025

Today we're announcing changes for the two versions of the Marketing Emails API.

Update for Legacy CTA Editor Sunset

Live: November 30, 2025

We have an essential update on the scope and timeline of a previously announced Legacy CTA sunset. Starting September 1st, 2025, all new CTAs must be created using the new CTA editor. Existing Legacy CTAs that have already been created will continue...

Upcoming Sunset of Clearbit’s Free Logo API

Live: December 1, 2025

In December 2023, Clearbit was acquired by HubSpot, marking the beginning of an exciting new chapter for both companies. Since then, the Clearbit team has fully integrated into HubSpot, combining our expertise with HubSpot’s resources to better...

Upcoming Sunset: HubSpot Academy CMS for Developers Certification

Live: May 30, 2025

What’s changing Starting on May 30, 2025, the HubSpot CMS for Developers Certification will no longer be available. The content of this course has been updated over the years but has hit a point that significant revisions are needed to to keep up...

Breaking Change: HubL Function Limits for Marketing Emails

Live: May 28, 2025

Beginning on May 28, 2025, we are enforcing the CMS HubL function limits for all customers using the following functions in their Marketing Emails, per our Software Products, Packaging, and Limits policies.

Breaking Change: Enhanced Validations for Non-String Properties in HubSpot's CRMObject APIs

Live: November 10, 2025

Starting November 10th, 2025, HubSpot will implement enhanced validations for non-string property values, including enumeration and multi-value enumeration property values submitted via the CRMObject APIs. This change aims to improve data integrity...

Upcoming Sunset: Growth default theme for the HubSpot CMS

Live: May 14, 2025

Note: This post has been updated to reflect an updated sunset date of March 28. The original date for this was March 15. What’s changing Starting on May 14, 2025, the default CMS Growth theme will no longer be available for new HubSpot portals....

Reminder: Breaking Change for Enhanced Validations for Non-String Properties in HubSpot's CRMObject APIs

Live: November 10, 2025

Starting November 10, 2025, HubSpot will introduce enhanced validation rules for non-string property values, including enumeration and multi-value enumeration submitted via the CRMObject APIs. This change aims to improve data integrity and user...

Breaking Change: Removed Support for Referencing Custom Object Types by Base Name

Live: June 4, 2025

We are removing the undocumented support for requesting custom object types by their base name (GET/crm/v3/objects/{baseName}) in HubSpot public APIs. All custom object types must be referenced by their unique identifier (object type ID, fully...

Update: Legacy CTA Sunset

Live: November 30, 2025

Attention: We've recently revised our timeline on March 25th, 2025. For the most current details regarding this change, please check the latest updates in our changelog. Based on community feedback, we have updated our approach to transitioning from...

Upcoming Sunset: V1 Contact Lists API

Live: September 30, 2025

Edit: we have extended the sunset date from May 30, 2025 to September 30, 2025 to allow more time for migrations. The below has been updated to reflect this change. What’s changing? The V1 Contact Lists API will sunset on September 30, 2025. After...

Legacy CTA Sunset Timeline and Scope Update

Live: November 30, 2025

Attention: We've recently revised our timeline on March 25th, 2025. For the most current details regarding this change, please check the latest updates in our changelog.

Upcoming Sunset: Legacy CTAs

Live: November 30, 2025

Attention: We've recently revised our timeline on March 25th, 2025. For the most current details regarding this change, please check the latest updates in our changelog. We are sunsetting the Legacy CTAs (Call-To-Action) app and migrating it into a...

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Latest Posts

New Size Limits for App Events and App Event Properties

Changes to list membership actions in the v4 Automation API

February 2025 Rollup

Removing deprecated event types from the Event Analytics API

Breaking Change for v3 Lists API Beta

Final Reminder: Sunset of v2 Owners API

Marketing Email API: v3 released to general availability and upcoming sunset for v1

Update for Legacy CTA Editor Sunset

Upcoming Sunset of Clearbit’s Free Logo API

Upcoming Sunset: HubSpot Academy CMS for Developers Certification

Breaking Change: HubL Function Limits for Marketing Emails

Breaking Change: Enhanced Validations for Non-String Properties in HubSpot's CRMObject APIs

Upcoming Sunset: Growth default theme for the HubSpot CMS

Reminder: Breaking Change for Enhanced Validations for Non-String Properties in HubSpot's CRMObject APIs

Breaking Change: Removed Support for Referencing Custom Object Types by Base Name

Update: Legacy CTA Sunset

Upcoming Sunset: V1 Contact Lists API

Legacy CTA Sunset Timeline and Scope Update

Upcoming Sunset: Legacy CTAs