Guide
UTM parameters for affiliates and partners
Affiliate networks have their own click IDs for commissions. Your GA4 property still needs a source, medium, and campaign if you want those visits next to ads and email. A payout report that does not match the site is how partner marketing gets accused of fraud when the real issue was an untagged landing URL.
The pattern that files as Affiliates
| Parameter | Put this | Example |
|---|---|---|
utm_source | Partner or network slug | partner-acme, shareasale |
utm_medium | Always affiliate | affiliate |
utm_campaign | Your program, not their site name | always-on-catalog, spring-sale-2026 |
utm_content | Publisher, placement, or coupon | pub-1842, homepage-mod |
utm_term | Optional offer or audience | new-customer |
utm_medium=affiliate is how default channel grouping can place the session in Affiliates. referral dumps partners into Referral next to random blogs. cpc makes a partner look like paid search. Check the pair in the channel checker.
Use one campaign name for the commercial program you are running with them. If the spring sale is also in email and Meta, use the same spring-sale-2026 string so Traffic acquisition can roll the initiative up. Why that rollup matters: why track campaign traffic.
Who owns which field
You own medium and the campaign pattern. Partners own the temptation to “improve” the URL. If every publisher picks their own medium, you get Unassigned and three Affiliate rows that do not add. Write the allowed sources in the spreadsheet: one slug per partner, lowercase, no domains. A new publisher gets a new source or a new content value — not a new medium.
What you send the partner
Send a finished URL, not a paragraph of instructions. Build it in the campaign URL builder (Affiliate / partner preset on templates) or a row from the bulk generator if you have twenty publishers on the same program. Example:
https://example.com/shop?utm_source=partner-acme&utm_medium=affiliate&utm_campaign=spring-sale-2026&utm_content=newsletter-slot
If they wrap it in their redirect, click the public link yourself and confirm the query string survives. Same test as ads: the address bar after redirects is the truth.
What they send back
Partners paste from last year. They Title-Case the source. They add utm_medium=cpc because “it is paid.” They drop campaign. When a “working” link comes back, compare it to what you sent, or clean and validate it. Do not argue in email about a URL you have not decoded. The decoder ends that thread.
Network click IDs vs UTMs
Impact, Awin, CJ, ShareASale, and Amazon Associates append their own keys for attribution and cookies. Leave those keys alone. Do not delete them to make the URL “look like a UTM.” Do not copy a click ID into utm_content. The two systems answer different invoices: the network pays the publisher; GA4 tells you what happened on the site. Inspect unknown keys with the click ID inspector (it will not know every network key; leftover query params still show in the decoder’s other bucket).
Influencers who are paid but not in a network are still usually paid_social or a documented exception — not affiliate — unless they are actually on a commission deal. Naming: conventions. Mistakes partners repeat: common UTM mistakes.