Attribution Windows: How Long Should an Influencer Get Credit for a Sale?

What an attribution window is

An attribution window is the length of time after a touchpoint — a click, a view, or a visit through a link — during which a resulting purchase is still credited to that touchpoint. If a customer clicks an influencer's link today and buys in ten days, that sale only counts if the window is at least ten days long. Set the window to seven days, and that same sale disappears from tracking entirely and gets recorded as organic or direct, even though the influencer genuinely caused it.

There is no single universal correct window. Four different systems are typically in play at once in an influencer campaign, and each one sets — or lets you set — the window differently: the cookie-based tracking link, the discount code, and, if the content also runs as a paid ad, Meta Ads Manager and TikTok Ads Manager. If you use Google Analytics 4 to measure the broader organic effect, GA4 sets yet another window on top. For the full setup of tracking links, discount codes and UTM parameters working together, see how to track influencer marketing performance.

The three different "windows" actually in play

It's worth separating three distinct things that all get called an "attribution window" but behave very differently:

• Click-through window: how long after a click a purchase still counts. The most commonly discussed window, and the most generous one — the customer actively showed interest.
• View-through window: how long after a view with no click a purchase still counts. Typically much shorter, because the signal is weaker — you only know the ad was seen, not that the customer noticed it.
• The cookie's actual lifespan: the technical ceiling on how long the browser genuinely remembers the click at all, regardless of whatever window you've configured in your analytics tool or ad platform. This ceiling is set by the browser, not by you — see the Safari section below.

How the major platforms set their windows

None of the platforms share a common default, and only two of them — the discount code and GA4's lookback setting — are genuinely under your own control.

Why the cookie can expire before your window does

This is the part almost no brand checks, and it turns a configured 7-day or 30-day window into a theoretical ceiling rather than a real one for a meaningful share of traffic. According to Google's own documentation for GA4 cookies, GA4's JavaScript tags set first-party cookies directly in the browser to recognize users and sessions. Browsers enforce their own limits on how long such a cookie can live if the user doesn't return: up to 400 days in Chrome — but only 7 days in Safari, according to Google's own documentation.

Safari's Intelligent Tracking Prevention (ITP) goes further for exactly the kind of link an influencer campaign uses. According to WebKit's own documentation (the browser engine behind Safari), the lifespan of a JavaScript-set cookie drops to 24 hours when the landing page is reached via a link carrying a query string or fragment — precisely what a UTM-tagged tracking link is — and the link comes from a domain ITP has classified as a likely tracking source. Apple doesn't publish exactly which domains get that classification, but the mechanism targets exactly the shape of link influencer tracking is built on: a UTM-tagged link, clicked from inside a platform's own in-app browser.

This ties directly to two other tracking gaps already covered in the Academy: for the parameter-by-parameter build that makes a link "decorated" in the first place, see UTM parameters for influencer campaigns; and for the other reasons a genuine influencer sale can disappear from Google Analytics entirely, see why influencer sales don't show up in Google Analytics.

In practice, that means a meaningful share of your iPhone traffic can lose its cookie after 24 hours or 7 days — regardless of whether you've set a 7-day or a 30-day window in GA4 or on the tracking link itself. The window you configure and the time the cookie actually survives in the browser are not the same thing.

Why the window's length changes the numbers

Too short a window cuts the journey off before the customer has time to act, and so systematically undercounts the influencer's real effect — especially for products with a longer consideration time. Too long a window risks the opposite: crediting the influencer for a sale that genuinely happened for another reason in the meantime — a different campaign, a price drop, or organic interest that would have shown up anyway. See the broader discussion of how the attribution model and the window interact in influencer marketing attribution explained.

Worked example: how much a short window misses

The numbers below are hypothetical and for illustration only. This is not a real Make Influence customer case, and none of the figures are benchmarks.

Assume 100 purchases genuinely trace back to clicks on a creator's tracking link within 30 days of the click, distributed like this:

• Day 0 (same day): 40 purchases
• Day 1: another 15 purchases (running total: 55)
• Days 2–7: another 20 purchases (running total: 75)
• Days 8–30: another 15 purchases (running total: 90)
• After day 30: another 10 purchases (running total: 100 — none of the four windows below catch these)

That gives the following visibility, depending on the window in use:

• 1-day window (Meta's and TikTok's typical view-through default) = 55 of 100 = 55%
• 7-day window (Meta's and TikTok's click-through default) = 75 of 100 = 75%
• 30-day window (close to GA4's default for other key events) = 90 of 100 = 90%
• Even a 30-day window misses 100 − 90 = 10 purchases, i.e. 10% — customers who simply took longer to decide.

On top of that, some share of those "visible" 55–90 purchases may never actually get recorded in practice if the customer is on Safari and the cookie has already expired after 24 hours or 7 days — entirely independent of whatever window is set in the analytics tool.

Decision framework: which window for which situation

• IF the product is an impulse purchase with a short consideration time → a short window (1–7 days) captures most of the real effect; a long window mostly adds noise.
• IF the product has a longer consideration cycle (higher price, a considered decision) → use a longer window, or lean on a discount code, which isn't limited by a cookie at all.
• IF a large share of the audience is on iPhone/Safari and the link is typically clicked from inside a platform's own app → don't assume the cookie survives more than a few days; use a discount code as the primary tracking mechanism, not the link alone. See the full comparison in discount codes vs tracking links.
• IF you're running the influencer content as a paid ad on Meta or TikTok → set the platform's own window deliberately based on your funnel, rather than leaving it on the default.
• IF you're comparing two campaigns' performance → make sure they genuinely ran with the same window. A longer window will structurally show a bigger number for the exact same campaign.

Make Influence's operational perspective

In Make Influence's experience, the most common mistake is comparing two influencers' or two campaigns' numbers without checking whether they actually ran with the same attribution window — and drawing a conclusion about who performed better when the real difference is just the window's length. The second most common mistake is assuming a 30-day window in GA4 means tracking genuinely covers 30 days for all traffic. It doesn't for Safari users whose cookie has already expired.

We recommend keeping the window consistent across any campaigns you plan to compare, and always running a discount code alongside the tracking link — precisely because the code isn't subject to the browser's ceiling, and so still catches the sale even once the cookie is long gone.

FAQ

What's the difference between a click-through window and a view-through window?

The click-through window applies to purchases following an active click. The view-through window applies to purchases from customers who saw the content or ad but didn't click. View-through windows are almost always shorter, because the signal is weaker.

Why do GA4 and Meta show different numbers for the same sale?

Because they use different windows and often different attribution models. See the broader explanation in influencer marketing attribution explained.

Can I set my own window for a discount code?

Yes — and it's effectively unlimited, because the code doesn't depend on a cookie. The only real limit is how long you're willing to accept the risk of the code leaking or being misused.

Does a shorter window mean I'm losing real sales?

Yes, statistically. The worked example above shows how large a share of genuine purchases can fall outside a short window.

Should I always choose the longest window available?

No. Too long a window can credit the influencer for sales that genuinely happened for another reason. Match the window to the product's actual consideration time — not to whichever number produces the best-looking report.

Does the attribution window affect whether I should use a tracking link or a discount code?

Yes. The longer the consideration time and the more Safari users in the audience, the more the discount code matters, because it isn't limited by a cookie's lifespan. See discount codes vs tracking links for the full trade-off.