Forward server-side conversions to the Reddit Conversions API via PostHog's Reddit Conversions API destination.
Reddit's Conversions API (CAPI) receives conversions server-side, matched by hashed email and Reddit's rdt_cid click-id. PostHog offers two Reddit destinations:
- Reddit Conversions API — server-side, no cookies. Use this for forwarding conversions.
- Reddit Pixel — browser-side; sets third-party cookies. Only if you want the client-side pixel managed through PostHog.
Read the overview first for shared identity & dedup behaviour. This page is Reddit-specific.
What you need
| Credential | Where to get it |
|---|---|
| Conversion Access Token | Reddit Ads → Events Manager → generate a conversion access token. It's a non-expiring key (no OAuth refresh — nice). |
| Account ID / Pixel ID | Your Reddit Ads account identifier. |
How matching works
PostHog pre-fills the mapping with:
- Hashed email — SHA-256, lowercased and trimmed, from the person profile.
external_id— your stable user id.click_id— Reddit's click-id, captured browser-side from therdt_cidURL parameter on ad landings.ip_addressanduser_agent— best-effort, when available.
See the identity prerequisites — capture rdt_cid in the browser and identify() with email.
Recommended events
Forward real conversions — purchase, user_signed_up, lead_captured, subscription_created — with value + currency where it applies.
Deduplication
Reddit de-dupes on conversion_id (PostHog defaults it to the event UUID). If you also run the Reddit Pixel client-side, send the same id on both so each conversion counts once.
Only forward conversions for users who've consented to ad tracking. The Conversions API endpoint is ads-api.reddit.com/api/v2/conversions/events/{account_id} — PostHog calls it for you; you don't build the request.
Reddit reference: Send conversion events with the API.