UTM parameters
A set of query-string tags (utm_source, utm_medium, utm_campaign, utm_content, utm_term) that Google Analytics and similar tools use to attribute traffic to specific marketing efforts. Layered on top of affiliate tracking, not in place of it.
UTM parameters were introduced by Urchin (acquired by Google in 2005 to become Google Analytics). They live in the URL: ?utm_source=youtube&utm_medium=video&utm_campaign=spring-tech-review. When a visitor clicks, GA reads the parameters and records the session as originating from those values. It is purely analytics-side; UTM parameters have no effect on the merchant's side or on affiliate commission attribution.
For affiliate creators, UTM parameters complement affiliate sub-IDs without replacing them. Sub-IDs answer "which placement converted into a sale?" (the network's view). UTM parameters answer "which placement sent the traffic?" (your analytics view). Use both when the destination is your own site; use only sub-IDs when the destination is directly the merchant.
Related terms
Sub-ID
An optional label appended to an affiliate URL that lets you attribute conversions to a specific placement, content piece, or campaign. Every major network supports them; almost no creators use them well.
GlossaryAffiliate link
A URL that contains a tracking parameter identifying you as the referrer, so the merchant can credit you a commission when the click converts to a sale.
GlossaryLast-click attribution
The model affiliate networks use to credit commissions: whoever was the last affiliate to send a visitor before they purchased gets the commission, regardless of who introduced them to the product.
GlossaryAttribution window
The full timeframe during which a conversion can still be attributed to an earlier touchpoint. Broader than the cookie window in that it includes server-side and cross-device attribution mechanisms that operate beyond browser cookies.