UTM parameters: links that say where a visit came from
UTM parameters are the tags added after a question mark in a link, such as utm_source=newsletter. Analytics reads them on arrival, so a visit from your newsletter counts as the newsletter even when the mail app sends no referrer.
The formula
An example
A sponsored newsletter links to example.com/?utm_source=newsletter&utm_medium=email&utm_campaign=sponsor-november. 640 people arrive with it and 11 of them pay €286 in the next weeks. Against the €400 the issue cost, that is an ROI of −29% so far, with €48 a month still coming in.
Work it out with your numbers →How Sumly counts it
- utm_source names the source when it is set, before the referrer: a visit from a mail app, which sends no referrer, still counts as the newsletter.
- utm_campaign groups visits on ROI under Campaigns; tie the campaign's cost to it and you see what it returned.
- A ref or via in the link (?ref=maya) names a creator or partner, so each gets their own row under Ref links.
- Visits that come with no tags still count, by the site that sent them; Sumly marks the days one of them sends many more people than usual.
Mistakes that make it lie
- Tagging links between your own pages. A visitor who clicks one starts over as if they came from that campaign.
- Writing the same source two ways, TikTok and tiktok-ads. Pick one spelling for each place and keep to it.
- Expecting tags in a TikTok or Instagram caption to count. Those links cannot be tapped; put the tagged link in the bio.
Questions
Which UTM parameters are required?
None strictly, but utm_source, utm_medium and utm_campaign together answer where, how and which push. utm_content tells two ads or videos of one campaign apart; utm_term is for search ad keywords.
Do UTM tags work for apps?
For a link to your site, yes. A link straight to the App Store loses them; Apple counts store downloads per link with its own campaign token (ct) in App Store Connect instead.
Is a ref link the same as a UTM tag?
It does the same for one person: ?ref=maya says which creator or partner sent the visit, and is shorter to share.
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