The ignore-referrer setting
The ignore-referrer setting (an unwanted-referrals / referral exclusion list in GA4) tells analytics to treat traffic from specified hostnames as not a referral, so it does not start a new session or overwrite source attribution. The classic case is a third-party payment domain: without exclusion, returning shoppers look like they came from the payment provider. It is a configuration that protects session and source integrity.
What it does
By default, returning to your site from another hostname can register as a referral and start a new session attributed to that host. The ignore-referrer / unwanted-referrals configuration marks listed hostnames so their traffic is not treated as a referral. Source/medium is preserved across the round trip, and a single user journey stays one session rather than fracturing.
When to use it
The canonical use is checkout and authentication redirects: payment gateways, hosted login, and identity providers that bounce the user back to your domain. Without exclusion, conversions look like they came from the payment provider and original campaign attribution is lost. List the intermediary hosts you control the round trip with. Do not over-exclude genuine referrers, or you will hide real acquisition sources.
- Listed hosts are not treated as referrals
- Preserves source/medium across redirects
- Common for payment, SSO, and auth domains
How it appears in analytics and logs
Sessions attributed to a payment or SSO hostname usually mean that domain is missing from the referral exclusion list, splitting one journey into two sessions.
Diagnostic use case
Stop a payment or auth domain from hijacking attribution by listing it as an unwanted referral, so a return to your site does not start a new, misattributed session.
What WebmasterID can help detect
WebmasterID's first-party attribution can disregard known intermediary hosts similarly; the GA4 referral-exclusion control is documented here for parity.
Common mistakes
- Leaving payment/SSO domains off the list and misattributing conversions.
- Over-excluding real referrers and hiding acquisition sources.
- Assuming exclusion removes data rather than reshaping attribution.
Privacy and accuracy notes
The setting works on hostnames, not personal data. It changes attribution logic only and stores no identity; keep host lists to domains, not user information.
Related pages
- Cross-domain measurement
Cross-domain measurement lets GA4 treat a user moving between domains you own as one journey rather than two visitors. It works by passing a linker parameter on outbound links so the destination domain recognises the same session. Without it, each domain starts a fresh session and self-referral noise appears. It is essential when a single funnel spans, say, a marketing site and a separate checkout domain.
- Cross-domain tracking and the linker
Cross-domain tracking keeps a single session intact when a user moves between two domains you own — for example a marketing site and a separate checkout domain. GA4 does this with a linker that appends the client id to outbound links as a URL parameter (_gl), so the destination domain recognises the same user. Without it, the second domain starts a fresh session and attribution breaks.
- Direct traffic: what it really means
Direct traffic is the bucket analytics uses when no referrer is available. It includes genuine type-ins and bookmarks, but also a large share of visits whose referrer was stripped — app opens, HTTPS-to-HTTP transitions, shorteners, and privacy settings. Treating 'direct' as a single intent is the classic analytics mistake.
- Attribution analytics
Keep source attribution intact across redirects.
Sources and verification notes
Last reviewed 2026-06-24. Facts are checked against primary/official sources where available; uncertain specifics are marked “Data not yet verified” rather than guessed.