Attribution Window

Your Meta dashboard is reporting a very different ROAS than your Google dashboard for the same customer. Both numbers are technically correct. They’re measuring different windows of time.

An attribution window is the look-back period during which a platform claims credit for a conversion. Meta’s default is 7-day click and 1-day view: any purchase within 7 days of a click, or within 1 day of an impression, counts as a Meta conversion. Google’s default click window for most conversion types is 30 days. The same purchase made 10 days after a click is a Meta miss and a Google credit.

How it shows up in the wild

The HQ Digital — D2C performance agency — published attribution window audit data from a real Meta account. Under the platform default (7-day click + 1-day view), the account reported 6.2x ROAS. Narrowed to 7-day click only: 4.1x. Narrowed to 1-day click only: 2.8x.

The same campaigns. The same spend. The same period. Three different numbers depending on the active window. Switching from 1-day click to 7-day click produces a 30–50% overnight ROAS increase with no underlying performance change, per their published analysis.

Meta removed two attribution window options from Ads Manager on January 12, 2026: 7-day view and 28-day view. Both had credited conversions to users who saw an ad without clicking. Their removal cut the maximum view-based attribution look-back from 7 days to 1 day.

Brands running either removed window saw their reported conversion counts fall the following morning with no change in actual purchases, as documented by DOJO AI. The remaining options — 1-day click, 7-day click (the default), and 1-day view — are now the only settings available in Ads Manager.

Why it matters

The window you’re using shapes the conversion signal your campaign bidding receives. Longer windows give the algorithm more events to optimize toward — that can improve delivery, but it also pulls in purchases the ad may not have caused. My hunch is that most D2C brands running Advantage+ Shopping Campaigns don’t know what attribution window is active. Creative and budget decisions get made against ROAS numbers that are partly a measurement artifact.

Related terms

• ROAS (Return on Ad Spend) — the metric most directly inflated or deflated by window choice
• Cross-Channel Attribution — what happens when Meta and Google measure the same purchase through different windows
• First-Party Data — Conversions API and server-side events partially restore the signal iOS 14 degraded, determining what the window can see at all
• Meta Advantage+ Shopping Campaigns — attribution window settings interact directly with this campaign type’s automated bidding

Frequently asked questions

Does changing the attribution window change my actual performance? No. It changes what gets reported, not what happened. Sales are sales. The window determines how many of them the platform takes credit for.

Which attribution window should I use on Meta? For most D2C products with consideration cycles under a week, 7-day click is the common default and usually the right starting point. For impulse-priced products under $30, 1-day click gives a cleaner signal — it’s easier to tell which ads drove same-session decisions. The 1-day view window (included in Meta’s default) credits conversions to people who saw but never clicked; separating it from click attribution shows you what clicks are actually worth on their own.

If I change the window mid-campaign, will Meta’s algorithm reset? Yes. The algorithm has learned which users convert under the existing window’s definition. A narrower window changes who counts as a converter, and the system re-learns against that new signal. Expect a 1–2 week learning phase after any significant window change.