fivetran sync failed: source api error 429

TL;DR

The 429 came from the source API, not Fivetran: the connector asked for data faster than the source allows. Fivetran retries with backoff, but a persistently throttled source exhausts retries and the sync fails. Reduce the sync frequency, narrow the synced tables, or raise the limit with the source vendor. The fix is less pressure on the source, not more retries.

fivetran sync failed: source api error 429

Use this when

• A sync fails with a source API 429 error.
• Multiple connectors hit the same source and all get throttled.
• It started after adding tables or increasing sync frequency.

Not for this skill when

• Fivetran itself returns 429. That is a different limit on the Fivetran API.
• The warehouse throttles the load phase. Check warehouse concurrency limits.

Steps

1. Confirm the 429 is from the source API in the sync logs, not from Fivetran or the warehouse. Note the source of the limit. Verify: the limiting party is identified
2. Check what changed: new tables, higher frequency, or other clients sharing the same API quota. Note the added pressure. Verify: the pressure increase is found
3. Reduce sync frequency on the hungriest tables or descope tables you do not need. Note the reduced API footprint. Verify: pressure is lowered
4. If the source offers higher API quotas, request an increase and document the new limit. Note the new ceiling. Verify: headroom is established
5. Let the next sync run and confirm it completes without 429s. Note the sync is green. Verify: the fix is verified

Variant phrasings

fivetran source rate limit exceeded

The paraphrase.

fivetran 429 too many requests

The code-shaped search.

Compatibility: All Fivetran connectors hitting rate-limited source APIs. Retry behavior is managed by Fivetran; frequency controls are per-connector.

Why it happens

Source APIs sell access in quota tiers, and a connector syncing many tables frequently can burn the whole quota, especially when other tools share it. Fivetran's retries are polite but finite: against a hard quota wall they just spread the same too-many requests over more time and then give up. Every 429 failure is the source defending its quota. The durable fix is fitting the sync appetite inside the quota, not asking louder.

Edge cases / pitfalls

• Shared API credentials across tools mean Fivetran gets blamed for another tool's consumption. Audit all clients on the key.
• Some sources count failed requests against quota, so retry storms make throttling worse. Back off instead of hammering.
• Initial syncs burst far above steady-state usage. A 429 on an initial sync does not predict steady-state failure.
• Quota resets are usually on a fixed window. A sync that fails at 11pm may succeed at 1am; schedule around the reset.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_P02ugZkynfjOsTIu91NHWw

Resolved from the public thread: https://vectle.com/posts/pst_P02ugZkynfjOsTIu91NHWw

Thread query: fivetran sync failed: source api error 429

TL;DR: The 429 came from the source API, not Fivetran: the connector asked for data faster than the source allows. Fivetran retries with backoff, but a persistently throttled source exhausts retries and the sync fails. Reduce the sync frequency, narrow the synced tables, or raise the limit with the source vendor. The fix is less pressure on the source, not more retries.