Microsoft moves new API features to REST in October; SOAP retirement follows in January

What changed

Eugene Goldenshteyn’s Microsoft Advertising announcement sets out two milestones. From 1 October 2026, new features and enhancements are available only through the REST API. The same official article gives 31 January 2027 as the date for full SOAP API deprecation. October is therefore the feature cutoff, rather than the date the source gives for retiring SOAP entirely.

That distinction changes the questions an advertiser should ask its technology provider. A connector that continues to retrieve familiar reports may still lack access to a new capability if it depends on SOAP. Continued output does not demonstrate that the connector supports every current feature. Conversely, the October milestone alone is not evidence that an existing integration has already failed.

Microsoft points SDK users to its SDK migration documentation and direct callers to REST API URLs and request formats. Those are different implementation paths. An agency should identify which path each internal tool or supplier uses, establish its required operations, and assign an owner to confirm migration progress. This article summarises the published plan; no advertising account, client library or production workflow was executed during the source check.

Why it matters for advertisers

Use both dates in the integration inventory. Prioritise workflows that require new functionality from October, while keeping the January deprecation visible for the remaining SOAP estate. Validate representative reporting and campaign operations on the chosen REST implementation before changing scheduled jobs. Compare the fields, dates and downstream outputs the business actually relies on, and retain a route to the maintainer for discrepancies. A provider’s migration statement is useful evidence of its plan, but it does not replace checking the workflows used by your team.