What are UTM parameters?

The five standard tags

https://example.com/spring-sale/?utm_source=newsletter&utm_medium=email&utm_campaign=spring_sale_2026&utm_content=header_button

Source and medium are the essential pair, and campaign is used in nearly every case. Term and content are optional. Google Analytics also recognises a few newer ones, such as utm_id.

Naming rules that save pain later

Analytics treats values as plain text and is case-sensitive, so Email, email and e-mail become three separate rows.

• Use lowercase throughout.
• Use hyphens or underscores, never spaces.
• Use the medium values your analytics tool expects for its default channel groups, such as email, cpc, social and referral. An invented medium ends up in "Unassigned".
• Keep a shared list of sources and campaign names, so two people do not tag the same newsletter differently.
• Put nothing personal in a tag. URLs are stored in logs and histories.

Our UTM builder assembles the URL and encodes the values correctly.

SEO side effects

A tagged URL is a different address serving the same content, so it is a potential duplicate.

• Canonical tags handle it. A self-referencing canonical on the clean URL appears on the tagged version too and points search engines back to the original. Confirm that your canonical does not copy the query string.
• Never tag internal links. A menu or banner link with UTM tags overwrites the visit's original source in analytics, so a visitor who arrived from Google is suddenly credited to "homepage_banner". It also creates crawlable duplicate URLs across the site. To measure clicks on internal elements, use event tracking.
• Tagged URLs get shared. People copy the address bar, tags included, into forums and posts. Those links then report misleading sources and add more URL variants. The canonical tag consolidates them for search engines.
• Redirects must keep the query string. If the tagged URL redirects, for example from http to https or to a trailing slash, the tags need to survive the hop or the attribution is lost.
• Mind the fragment. Tags go before any #. In example.com/page/#top?utm_source=x they are part of the fragment and never reach analytics.
• Caching. Some page caches treat each distinct query string as a new page, which lowers the cache hit rate during a big campaign. Many caching layers can be set to ignore utm_ parameters.

Where to use them and where not

Use them on: email newsletters, paid ads that are not auto-tagged, social posts and profile links, QR codes, links in PDFs, and partner or affiliate placements.

Skip them on: internal links, links where the ad platform's own auto-tagging is active and already reports to your analytics, and organic search results, which you cannot tag in any case.

A link to your site from another website's article is best left untagged unless you control it. Analytics already records the referring site.

A WordPress note

WordPress ignores query parameters it does not recognise, so a tagged URL loads the normal page with no extra setup. Check two things on your own site: that the canonical tag on a tagged request shows the clean URL, which SEO plugins including Hydrogen SEO output by default, as described in canonical URLs, and that redirects created for moved pages carry the query string through. If Search Console starts listing tagged addresses as duplicates, that is the canonical doing its work, and nothing needs fixing.