LinkedIn Marketing API 202509 has passed its retirement date

What changed

LinkedIn’s current migration table marks Marketing API version 202509 as deprecated and retains 15 September 2026 as its sunset date. The deadline has passed. The September release notes identify 202609 as the latest version and list 15 October 2026 as the next sunset, for version 202510. These are API maintenance dates, not evidence that a particular advertiser’s connector has failed.

The version identifies the API contract an integration uses, rather than the dates of the campaigns or reports it retrieves. Teams still analysing older campaign data need a supported API version too. A reporting period and a release version answer different questions, so a historical export should not be assumed to require an obsolete version.

Start with the workflows that run without someone watching them: reporting connectors, scheduled exports and internal tools. Ask each owner or vendor which version their requests use and whether migration is complete. A successful sign-in or an old report in a dashboard does not establish that the latest scheduled request succeeded. Inspect a recent run and its output before treating the migration as finished.

Why it matters for advertisers

The useful outcome is continuity of the business process. Review the migration guidance for the endpoints each integration actually uses, confirm a supported destination version and compare representative output. For reporting, check expected fields, date ranges and downstream totals. Campaign creation or editing needs its own validation. If the team uses a third-party connector, request its current migration status rather than assuming that a local account setting controls its API version. This source check does not certify any connector, script or live advertising workflow.