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Attribution Audit

An attribution audit checks that the tracking, tags and reports behind your marketing budget still measure what they claim to, best run each quarter.

By , Founder & CEOPublished 4 min read

What is Attribution Audit?

An attribution audit works through four questions in order. Are purchases still recorded, so that GA4's purchases track the orders your store took? Do visits still arrive with their source, or is more of your traffic landing in Direct and Unassigned? Do the ad platforms' claims add up to more than you sold? And do the channels you pay for still cause sales, which only a holdout test or a causal read can answer?

The quarterly attribution checkup is the same audit on a schedule. Like a dental checkup, most visits find nothing, and the schedule is the point: budgets are set by quarter, the channel mix drifts, and tags and consent settings break without anyone noticing. Between checkups, run it again after a tracking or site change, when you add or cut a channel, before peak season, and whenever a platform's ROAS and your revenue disagree.

A causal attribution read like Causality Engine's answers the last question from one GA4 export: what each channel caused next to what last-click gave it, with Direct split back to the channels that sent those buyers.

Why Attribution Audit matters for ecommerce

Every budget decision reads the same numbers, so an error in them spreads quietly. A purchase tag that broke early in a quarter sits inside every report and every reallocation made since. Each ad platform grades its own homework, counting the sales it can connect to its own ads inside its own window, so none of them is placed to notice that GA4 stopped counting.

An audit on a fixed schedule turns a silent drift into a dated finding, caught in the quarter it started. Done after the damage, the same check can only explain it.

How to use Attribution Audit

  1. Compare GA4's purchases for the quarter with the orders your store recorded for the same dates, and place a test order to confirm the purchase event still reaches GA4.
  2. In GA4's Traffic acquisition report, note how much of your sessions and revenue sits in Direct and Unassigned, and work out how much arrives with UTM tags.
  3. Add up the revenue each ad platform reports and set it against your store's revenue for the same dates.
  4. In GA4's Attribution paths report, read days to key event for buyers who saw two or more channels, and compare it with each platform's attribution window.
  5. Recompute break-even ROAS with this quarter's order value, margin, shipping, fees and returns.
  6. Plan one holdout test on the channel your next budget depends on most.
  7. Log the date, the gaps and the fixes, and start the next checkup by reading the log.

Common mistakes

  1. Auditing only when something looks wrong. By then the error has been in every report for weeks, and there is no clean earlier quarter to compare with.
  2. Checking the platforms against each other instead of against store orders. Each one counts inside its own window, so their totals overlap, and only your store says what was sold.
  3. Changing tracking during the audit. A new tag, channel grouping or consent setup in the same weeks makes the before and the after impossible to compare.
  4. Treating a clean audit as proof that channels work. An audit shows whether the data can be trusted. Whether a channel causes sales takes a holdout test or a causal read.
  5. Keeping no log. A number that moved since last quarter is easier to spot than a number that is wrong, and only a written log shows the movement.

Frequently asked questions

  • What is an attribution audit?
    A check that the tracking, tags and reports behind your marketing budget still measure what they claim to: that purchases are recorded, that visits keep their source, that platform claims do not add up to more than you sold, and that the channels you pay for still cause sales.
  • How often should you run an attribution audit?
    Once a quarter, before the next budget is set, and again after a tracking or site change, when you add or cut a channel, before peak season, and whenever a platform's ROAS and your revenue disagree.
  • What is a quarterly attribution checkup?
    The same audit on a fixed schedule, the way a dental checkup is. Most visits find nothing, and the schedule is how a broken tag gets found in the quarter it broke rather than in a budget review two quarters later.

Further reading

Your platforms guess.
We run the math.

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