End of Support for v1-v3 APIs and Legacy Apps
HubSpot is ending support for v1-v3 APIs, legacy public apps, and legacy private apps effective September 2027. Customers and partners have a 12-month window from the announcement to migrate to supported alternatives.
At Fall Spotlight on September 15, HubSpot is announcing the end of support for v1-v3 APIs, legacy public apps, and legacy private apps, all with a September 2027 enforcement date. If your integration or app uses any of these, you have a 12-month window to migrate.
This changelog covers v1-v3. Support for v4 is ending on its own separate timeline, March 30, 2027, which was announced earlier this year. See the previously published v4 changelog for that timeline.
This post covers breaking changes only. For everything new and non-breaking in this release, including the APIs reaching general availability, the updated APIs, the new public betas, and the latest AI builder tools, see the Fall Spotlight 2026 developer rollup.
Source: original entry ↗