Meta Ads March 2026 Attribution Update: Why Performance Looks Worse

Key Takeaways

Meta announced the change on 3 March 2026 and rolled it out across global ad accounts through late March and April. Click-through attribution now counts link clicks only.
Engage-through attribution is the new home for likes, reactions, comments, shares, saves, and engaged video views. It is enabled by default with a 1-day window.
The video and Reels engagement window shortened from 10 seconds to 5 seconds, because 46% of Reels purchase conversions now happen in the first 2 seconds.
Reported attribution accuracy dropped 40 to 60 percent on many accounts. Most of that is reclassification, not real performance loss.
Your campaigns are not broken. The rules of measurement changed underneath them. Read the new numbers correctly before you cut budget.
For NZ and Australian advertisers, the practical impact is the same as the US, but the volatility around the rollout was rougher because most local agencies did not see it coming.

If you opened your Meta Ads dashboard in late March or April 2026 and thought you were having a stroke, you are not alone. Reported click-through conversions fell off a cliff on accounts that had been running steadily for months. Reddit’s r/FacebookAds filled with threads asking the same question. “Is my account broken? Did the algorithm change? Should I pause everything?”

The answer is: your account is fine, the algorithm is making longer-horizon decisions, and you should not pause everything. Meta did rebuild attribution in March, and the new rules are different enough that the reported numbers genuinely look worse even when the underlying business is steady.

This post walks through what actually changed, why the numbers look the way they do, how to read the new reports, and what to actually do about it.

What actually changed in March 2026

Meta announced the click attribution update on 3 March 2026 and began rolling it out later that month. Three things changed at the same time, and the combined effect is what made dashboards look broken.

1. Click-through attribution narrowed to link clicks only. Before March, “any click” on your ad counted as a click-through conversion. That included social clicks like reactions, comments, shares, and saves. After March, only clicks on actual links count: website links, call buttons, messaging features, and lead forms. Meta’s own announcement framed this as bringing reporting in line with tools like Google Analytics, which has always counted only link clicks.

2. Engage-through attribution became the new home for the rest. Likes, reactions, comments, shares, saves, and engaged video views now feed a separate metric called engage-through. This is rebranded from the old “engaged-view” attribution and is enabled by default with a 1-day window. Search Engine Land’s coverage of the rollout called this the cleanest summary of what changed.

3. The video and Reels engagement window dropped from 10 seconds to 5 seconds. Meta cited internal data showing that 46% of online purchase conversions on Reels now happen within the first 2 seconds. Five seconds is now the threshold for an “engaged view” to count toward engage-through.

That is the technical change. The practical consequence is different.

Why your reported numbers look worse

If you compared your March or April numbers to February using default settings, here is roughly what happened.

Click-through conversions dropped, sometimes a lot. Conversions that used to land in click-through now land in engage-through. They did not disappear. They moved buckets. If you only look at click-through conversions in your reports, you are seeing a smaller subset of the same conversions you used to see.

Cost per click-through conversion looks higher. Same total spend, fewer conversions in the click-through bucket, so cost per conversion divides higher. Again, this is mathematical, not strategic.

ROAS in click-through reports looks worse. Same logic. Revenue tied to engage-through interactions now sits outside the click-through column.

Total reported conversions across both windows is roughly comparable. This is the most important point. If you add click-through and engage-through together, the total tends to land close to where your old “any click” attribution would have landed, sometimes higher because the new system also picks up signals it used to miss.

Dataslayer’s analysis found accounts where reported click-through conversions dropped 40 to 60 percent month over month while total conversions across both attribution categories barely moved. That is the pattern most accounts are seeing.

What about the algorithm? Did Meta change the underlying delivery system too?

This is where it gets murkier. Meta did not officially announce a delivery system change in March, but Andromeda — the AI-driven delivery model Meta rolled out in late 2024 — has continued to shift toward longer-horizon optimisation throughout 2025 and 2026. The combined effect is that:

Learning periods feel longer. Campaigns that used to stabilise in three to five days now sometimes need ten to fourteen.
CPMs are more volatile. Day-over-day swings of 30 to 50 percent are now normal on smaller budgets.
The first three days are misleading. Day three performance is no longer a reliable predictor of day fourteen performance.

This is partly the algorithm changing under you and partly the new attribution windows mixing with the old reporting habits. The fix is the same either way: stop killing campaigns on day three.

How to read the new reports correctly

Three practical changes to your reporting workflow will solve most of the confusion.

1. Always look at click-through and engage-through together

In Ads Manager, set your attribution comparison to show both 7-day click-through and 1-day engage-through. Do not look at click-through in isolation. Total conversions across both buckets is the closest analogue to your pre-March reporting.

2. Pick the right attribution setting per conversion event

Jon Loomer’s practical guidance is the cleanest take I have seen. The short version:

Purchase conversions: keep both 7-day click-through and 1-day engage-through enabled. Engagement is a real signal of interest and awareness even when another channel closes the sale.
Lead and form conversions: consider turning engage-through off. If someone did not click through to your lead form, the case that your ad caused the conversion is harder to make.
Video views, page likes, awareness goals: engage-through stays on. That is what those campaigns are for.

3. Stop comparing to last year for now

Year-over-year comparisons through March and April are unreliable. The buckets changed. The right comparison is total conversions across both windows, not click-through versus click-through. Mark your dashboards and your client reports with a note that “March 2026 attribution rebuild” applies, and move on.

The CAPI signal quality angle

The other half of this story is that weaker signals reaching Meta lead to worse delivery decisions, regardless of how attribution is reported. iOS privacy changes, browser cookie deprecation, and tighter consent requirements have all eroded the data Meta gets back from your website. The attribution rebuild made this more visible, but the underlying signal quality issue has been growing for years.

If you have not audited your Meta Conversions API setup since 2024, do it now. Specifically:

Event match quality (EMQ) above 7. This is the single biggest lever on signal quality. Pass hashed email, phone, FBC, FBP, IP, and user agent on every event.
Server-side deduplication working. Pixel and CAPI events for the same conversion should match by event ID and timestamp.
No missing parameters. Currency, value, content IDs on every purchase event. Missing parameters silently kill match rates.
Test events tab clean. No errors, no warnings, no fallback events.

When CAPI is healthy, the algorithm gets clean signal and Andromeda makes better calls. When CAPI is broken, you blame attribution, but the actual problem is data hygiene.

What this means for NZ and Australian businesses

The technical change is identical for NZ and AU advertisers. The practical experience was rougher because most local agencies did not see it coming and clients started panicking when reports dropped.

A few specifics for the ANZ market:

The rollout reached ANZ accounts on the same timeline as the US, which is a refreshing change from most Meta releases.
Local agencies with monthly retainer reporting got hit harder because their April reports landed before they had time to write up an explanation. We saw a wave of “fire the agency” conversations that should not have happened.
NZ small businesses with low spend are more exposed to CPM volatility because Andromeda has less data to optimise from. Tighter pacing and longer learning periods matter more on a $50/day budget than on a $5,000/day one.
The Australian market is feeling the engage-through shift more on awareness campaigns for retail and FMCG, where engagement-driven attribution always carried more weight.

If you run paid ads in NZ or Australia and your March, April, or May numbers triggered a panic response, take a breath. Compare across both windows, audit CAPI, and read the new reports correctly before you change anything.

How to actually fix it: a five-step playbook

For the next 30 days, work through this in order. Do not skip steps.

Pull a side-by-side report. Same date range, March and April 2026. Show click-through conversions, engage-through conversions, total conversions, total revenue, total spend.
Subtract the reclassification. Compare total conversions across both windows to your January and February total conversions on the old attribution. Most accounts will see a much smaller “drop” once you look at the combined number.
Audit CAPI. Check EMQ, dedup, missing parameters, test events. Fix anything that is not green.
Tighten attribution settings per conversion event. Purchases keep engage-through. Leads probably drop it. Awareness keeps it.
Hold the line on campaign decisions for two weeks. Do not pause campaigns that look bad on the new reports if they were healthy on the old ones. Watch the combined numbers and the actual revenue or pipeline.

If you want to move through this faster, you can point an AI tool at your account using the new Meta Ads MCP and have Claude or ChatGPT do the side-by-side analysis in seconds. We use this internally on every client account once a month. It turns a four-hour reporting exercise into a fifteen-minute prompt.

What we are seeing in client accounts

Three quick patterns from accounts we manage in NZ and Australia.

Ecommerce on a 30-day window: total conversions across both attribution categories are within 5 percent of February. Click-through alone is down about 35 percent. Real revenue tracked by Shopify is up 8 percent. The “drop” was a reclassification.

Service business with lead-form objective: engage-through conversions inflated reported leads in March before we removed it. Once we set the campaign to click-through only, the numbers matched the CRM. Lesson: turn engage-through off for non-purchase events unless you have a specific reason to keep it.

Local retail awareness campaign: engage-through made this campaign look better than it actually was. We had to add stricter on-site conversion tracking to validate that the engagement was translating into footfall.

The thread across all three is that the new attribution model is more honest, but you have to set it up correctly per conversion event, or it will mislead you.

Frequently asked questions

When did Meta change attribution in 2026? Meta announced the change on 3 March 2026 and began rolling it out to global ad accounts through late March and April. By early May 2026, the new attribution model is the default on most accounts.

Why did my Meta Ads click-through conversions drop in March 2026? Click-through attribution now counts only link clicks. Likes, reactions, comments, shares, saves, and engaged video views were moved into a new metric called engage-through. The conversions did not disappear. They moved to a different bucket. Total conversions across both buckets are usually close to the old reporting.

Should I turn engage-through attribution off? For purchase conversions, keep it on with the default 1-day window. The engagement is a real signal. For lead and form conversions, consider turning it off if you suspect engage-through is inflating reported leads that did not actually click through to your form. For awareness and video campaigns, keep it on.

Did Meta change the algorithm in March 2026? Officially, no. The Andromeda delivery system has continued to shift throughout 2025 and 2026 toward longer-horizon optimisation, but Meta did not announce a delivery change in March. Most of what feels like an algorithm change is the new attribution windows interacting with old reporting habits.

Are my Meta Ads campaigns actually performing worse? On most accounts we have audited, no. Combined click-through plus engage-through conversions are close to where they were before March. Real revenue tracked outside Meta is often steady or up. The drop is in reported click-through alone, which is a smaller bucket than it used to be.

What is engage-through attribution? Engage-through is Meta’s new attribution category for conversions that follow non-link interactions with your ad: likes, reactions, comments, shares, saves, and engaged video views (now defined as 5+ seconds, down from 10). It runs on a 1-day window by default and was rebranded from the old “engaged-view attribution” in March 2026.

Where to from here

Meta’s March 2026 attribution rebuild is the most disruptive measurement change advertisers have seen since the iOS 14 rollout. The good news is that, unlike iOS 14, this one is mostly a reporting change rather than a signal loss. Read the new numbers correctly, audit your Conversions API, and tighten your attribution settings per conversion event.

If you want a hand auditing your account or building an AI-assisted reporting workflow that handles the new attribution windows automatically, book a call with our team. We work with NZ and AU businesses on paid ads, measurement, and the connective tissue between them.

The numbers look worse. Most of that is the buckets, not your campaigns. Read the right buckets.