Meta conversion rates dropping: iOS 27 or the incremental attribution shift? (unconfirmed)
What changed
WATCHING / UNCONFIRMED. Meta has not announced any change that explains this, and nothing below is confirmed. The signal: on October 21, 2026, Nick Shackelford (@iamshackelford) posted "Meta made changes and absolutely fucked us" (about 24.5K views), and replies report conversion rates way down since Sunday. David Herrmann (@herrmanndigital) also posted "lots of issues on Meta atm. you're not alone." with an Ads Manager screenshot showing two errors: "Some draft changes not saved" and "Publish didn't complete". Theory 1: Steve Rekuc (@RSteveData) shared data showing Meta conversion rates falling from around October 1 and sharply from October 5, and asked whether the iOS 27 rollout is behind it. Theory 2: David Herrmann (@herrmanndigital) says it's the incremental attribution shift, and that he was told accounts that didn't get a pop-up aren't in it yet. Separately, advertisers in the replies say Meta switched things on by itself: new uploads converted to post-ID ads (@luismvestia), a CTA button removed from a top ad, Related Media turned on, and 30% of a daily budget spent in 20 minutes on Instagram Stories (@ricsbizz). These are anecdotes only. A third-party data point (Northbeam's data, not Meta's): on October 21 Northbeam said Meta CPMs are up about 25% year over year across the billions in ad spend it tracks, the highest during "normal" selling periods in about 18 months, and that the Black Friday/Cyber Monday CPM spike started in September this year versus November in 2025. Northbeam says CPMs rose after Meta's March 2026 click-through attribution change but calls that correlation, not causation, and says its data can't identify a root cause. Charts by Bryan Bumgardner. One related item that is confirmed: Funnel's status page says Meta confirmed a known Insights API issue from October 21 that can make spend, impressions and clicks show missing or low in third-party tools, including for past dates. That's a reporting bug, not a conversion drop, but it can make your dashboards look worse than Ads Manager. We'll upgrade this entry once Meta or solid data confirms the cause.
What to do
Does this affect you? 1) Did you get an attribution pop-up in Ads Manager? 2) Check the attribution setting in the Ads Manager UI itself, not through the API or a third-party tool. 3) In breakdowns, compare conversion rate on iOS vs Android since October 5. If only iOS fell, that points to measurement, not demand. 4) Open your newest ads and check the Advantage+ creative and Related Media toggles and that the CTA button is still there. 5) Check placement breakdowns for sudden spend spikes, especially Instagram Stories. 6) If your numbers come from a third-party dashboard (Funnel, Triple Whale and the like), check them against Ads Manager before you act, because of the Insights API issue.
Source
- Nick Shackelford on X: "Meta made changes and absolutely fucked us" ↗
- Steve Rekuc on X: Meta conversion rate drop since Oct 1 / Oct 5, possibly iOS 27 ↗
- David Herrmann on X: incremental attribution shift, no pop-up means not in it yet ↗
- Northbeam on X: Meta CPMs up ~25% YoY, BFCM spike started in September ↗
- Bryan Bumgardner on X: start of a run of 25+ charts ↗
- David Herrmann on X: "lots of issues on Meta atm" (Ads Manager publish errors) ↗
- IsDown (Funnel status): Meta confirmed Insights API issue, Oct 21, 2026 ↗
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