Play Billing Library: required version 8 by 31 August 2026—and what blocks updates

Google’s Play Billing Library deprecation FAQ states a two-year deprecation cycle and a near-term gate that measurement and release teams cannot ignore: by 31 August 2026, all new apps and updates to existing apps must use Billing Library version 8 or later. An extension to 1 November 2026 is available via Play Console if more time is needed. This record is a deadline checklist for studios whose purchase and subscription events feed UA revenue reporting—not a migration tutorial.

Current required version and deadlines

The Google Play Billing Library version deprecation page (last updated 9 September 2026 UTC) opens with the version-8 reminder and publishes this support timeline:

Reading the table with the banner reminder: shipping on version 7 or earlier after 31 August 2026 (or after an approved extension deadline) blocks new apps and updates. The FAQ states unmaintained APKs need not be updated for users who already have them, but new apps and updates must use a supported version from the table. Dependencies appear in APKs that require the com.android.vending.BILLING permission.

Extension process: if an unsupported library version is detected, Play Console shows a warning; the extension form is on the warning’s details page under Policy status.

Getting ready restates the same 31 August / 1 November 2026 reminder and shows a sample dependency on Billing Library 9.1.0, indicating the current recommended integration line is already ahead of the version-8 floor.

What this means for UA revenue events

Observation from the deprecation FAQ: apps that cannot publish updates on an unsupported Billing Library version cannot ship billing fixes, new SKUs or measurement SDK updates that ride the same binary. Vendor claim: Google will not accept those updates after the deadline without an extension. Editorial inference: overdue Billing Library upgrades are a release-train risk for purchase posting and subscription event quality used in UA ROAS—not proof that live users suddenly lose purchases on already-installed builds.

Release and measurement owners should:

1. Confirm billingclient version in build.gradle against the table (target ≥ 8.0.0 before 31 August 2026).
2. Verify com.google.android.play.billingclient.version survives manifest merge.
3. If still on 7.x near the deadline, file the Play Console extension and schedule the PBL 8 migration guide work.
4. Treat purchase/subscription instrumentation QA as part of the same release, because a blocked update freezes both store billing and client-side event wiring.

Limits of this record

This edition body-reads Android Developers documentation. It does not inspect a studio Play Console policy status, certify a binary, or measure revenue-event loss. Migration API details for versions 8 and 9 are out of scope except as pointers. The original I/O 2019 announcement of the two-year cycle is cited by Google on the FAQ; per-version enforcement history beyond the table is not re-litigated here.

Research checked 19 September 2026. Local draft; human editorial review and byline assignment pending.