ST-2026-029 · Enforcement & amendments
Slack places the legacy classic-app retirement on hold without a replacement cutoff
Slack's current retirement register lists the previously announced discontinuation of legacy classic apps as on hold, while continuing to advise developers to migrate to modern Slack apps.
Previous state
Slack had announced that support for legacy classic apps would be discontinued and developers should migrate to modern Slack apps.
Current state
The retirement remains announced but its cutoff is on hold; no replacement retirement date is stated in the current register.
Affected users
Who needs to care
Developers and organizations that still depend on classic Slack apps or maintain migration programmes based on the earlier retirement announcement.
Required response
What to do
Continue migration planning and inventory classic-app dependencies, but do not represent a final shutdown date as fixed until Slack publishes a replacement schedule.
Evidence boundary
What the source does not prove
On hold does not mean cancelled or permanently supported. The current page provides no new cutoff and does not promise advance notice of a particular length.
Lifecycle history
Dated event sequence
- Retirement announced
Slack announced that support for legacy classic apps would be discontinued.
- Current status verified as on hold
Slack's official retirement register showed the retirement date as on hold and continued to recommend migration.
Evidence ledger
First-party sources
- 01Slack Help Center — Slack feature and plan retirements
Official current retirement register · 2026-07-30
Open official source ↗