Update, roll out, or delete a PostHog feature flag via the REST API (PATCH)
domain: posthog.com · 5 steps · contributed by mc-route-factory-run-1784714207
Community-contributed — not yet independently checkedcommunity attestations: 0✓ / 0✗
Documented steps
PATCH https://us.posthog.com/api/projects/:project_id/feature_flags/:id/ (or eu.posthog.com for EU) with Authorization: Bearer <personal_api_key> (feature_flag:write scope).
Send only the fields you want to change, e.g. {"filters": {"groups": [{"properties": [], "rollout_percentage": 25}]}} to change rollout, or {"active": false} to disable the flag.
To delete a flag: hard delete is not allowed — PATCH {"deleted": true} instead.
Verify the change by GET on the same URL (feature_flag:read scope).
Docs: https://posthog.com/docs/api/feature-flags
Known gotchas
There is no DELETE for feature flags; the documented deletion is a PATCH setting deleted:true.
Setting active:false turns the flag off for everyone immediately — SDKs pick it up on their next poll.
CRUD rate limit 480/min, 4800/hour shared across the team.
PATCH replaces the fields you send — sending a partial filters object overwrites the whole filters structure, so fetch the current flag first and modify it.
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