Referral exclusions

Leave out some domains from your referral sources.

This feature is only available for properties using Universal Analytics.

Referral traffic is the segment of traffic that arrives on your website through another source, like through a link on another domain. Analytics automatically recognizes where traffic was immediately before arriving on your site, and displays the domain names of these sites as the referral traffic sources in your reports.

You can exclude specific domains from being recognized as referral traffic sources in your Analytics reports. A common use for this feature is to exclude traffic from a third-party shopping cart to prevent customers from being counted in new session and as a referral when they return to your order confirmation page after checking out on the third-party site.

Google Analytics automatically excludes the domain associated with a property as a referral source, so you won’t see self-referrals in your Analytics reports. You must manually add all other domains (including sites in a cross-domain tracking or third-party shopping cart setup) to exclude traffic from those sites as referral traffic in your reports.

Add or remove referral traffic sources

Adding referral traffic sources

Only traffic from the domain entered in the referral exclusions list and any subdomains are excluded. Traffic from domains that only have substring matches are not excluded.

For example, if you add example.com to the list of referral exclusions, traffic from the domain example.com and the subdomain another.example.com is excluded. Traffic from another-example.com is not excluded.

Sign in to your Google Analytics account.
Click Admin in the menu bar at the top of any page.
In the ACCOUNT column, use the dropdown to select the Analytics account that contains the property you want to work with.
In the PROPERTY column, use the dropdown to select a property.
Click Tracking Info.
Click Referral Exclusion List.
To add a domain, click +ADD REFERRAL EXCLUSION.
Enter the Domain name.
Click Create to save.

Removing referral traffic sources

If you’ve added a domain to the list of exclusions, you can reintroduce that traffic as a referring source in your reports by removing the domain from the list of excluded domains.

Follow steps 1-6 above. In the table, click remove in the row of the domain you want to remove. Click Delete domain to save.

How excluding referral traffic affects your data

By default, a referral automatically triggers a new session. When you exclude a referral source, traffic that arrives to your site from the excluded domain doesn’t trigger a new session. If you want traffic arriving from a specific site to trigger a new session, don’t include that domain in this table.

Because each referral triggers a new session, excluding referrals (or not excluding referrals) affects how sessions are calculated in your account. The same interaction can be counted as either one or two sessions, based on how you treat referrals. For example, a user on my-site.com goes to your-site.com, and then returns to my-site.com. If you do not exclude your-site.com as a referring domain, two sessions are counted, one for each arrival at my-site.com. If, however, you exclude referrals from your-site.com, the second arrival to my-site.com does not trigger a new session, and only one session is counted.

Taken from: https://support.google.com/analytics/answer/2795830?hl=en