UTM links: find the origin of visits without disrupting campaigns

Measurement and analysis · 6 min reading

To find the origin of visits with UTM links, adopt a common convention, add the parameters without modifying the useful destination, then test the link actually distributed. The UTM describe the declared provenance of a campaign. They do not guarantee the collection of each visit nor the complete reconstruction of the purchasing journey. Their reliability depends as much on the naming discipline as on the functioning of the site.

Key points

• Use the same names for the same source, the same medium and the same campaign.
• Keep the settings necessary for the page to function.
• Test the destination after redirects and from the delivery medium.
• Do not put any personal information in UTM values.

Give a clear role to each parameter

The Google documentation on campaign URLs distinguishes in particular:

• utm_source: the declared origin, for example a newsletter or a platform.
• utm_medium: marketing support, for example email.
• utm_campaign: the name of the operation followed.
• utm_content: The content variant or link location.
• utm_id: a campaign identifier, particularly useful for reconciling imported data.

Google recommends using source, medium and campaign together, and providing other parameters relevant to your device, including utm_id and utm_source_platform. Don’t add fields that no one will know how to maintain. A short, documented and actually applied convention is better than a sophisticated nomenclature left to everyone's interpretation.

Avoid fragmenting the same campaign

Values are case sensitive: Google distinguishes a source written in lowercase from the same source written with an uppercase. Choose lowercase, a stable separator, and values ​​without spaces or accents to make typing easier. This last choice is an organizational rule, not a technical obligation.

Create a shared registry with the destination, source, medium, campaign, content, final link and its manager. Keep the campaign name the same between channels when it is the same operation. To compare placements, modify the content rather than inventing a new campaign.

Build UTM links while preserving the destination

A URL without parameters receives a question mark before the first parameter. Subsequent pairs are separated by an ampersand. If the destination already contains parameters, add UTM to the existing string: do not create a second question mark or remove a necessary product filter or promotional code. If the URL contains an anchor introduced by #, the parameters must appear before this anchor, not after it, according to the structure of a URI described by MDN.

To generate links automatically, use a tool designed to manipulate URL parameters. MDN documents URLSearchParams, which allows you to read, add or replace a value. Replacing an existing UTM avoids keeping multiple competing values ​​for the same field. Always check the link obtained rather than its construction formula alone.

Preserve automatic ad tagging

Do not blindly replace identifiers added by an advertising platform. Google recommends automatic tagging with compatible integrations and describes the coexistence of manual and automatic marking. Their interpretation has rules and exceptions. A modification must therefore be tested in the device concerned, not applied to all announcements based solely on a UTM model.

Fictitious example: following links from a newsletter

In this illustrative example, a store announces its “atelier” collection by e-mail. She uses newsletter for the source, email for support and collection_atelier for the campaign. The main button receives main_button as content. The link is built on a fictitious destination:

https://example.com/collection?utm_source=newsletter&utm_medium=email&utm_campaign=collection_atelier&utm_content=bouton_principal

The link placed in the text keeps the same source, the same medium and the same campaign; only the content value becomes text_link. The team can then distinguish the locations without dispersing the operation between several names. No campaign results are assumed in this example.

Test links and read the correct report

Open the link from a test message or preview of the media used. Check the final page, its functions and the retention of useful parameters after redirects. If a redirect removes the UTM before it is read by the meter, the assignment may be lost. However, their absence in the final address bar does not, in itself, prove a failure: check the data actually collected. A well-marked link that breaks a variant selection is not acceptable either.

Google indicates that campaign data can be viewed in Traffic Acquisition. In particular, use the source, medium and campaign dimensions associated with the session. The scope documentation distinguishes these dimensions from those of first user acquisition and attribution of key events. They do not answer the same question.

Checklist before broadcast

1. Validate the destination without UTM and its existing parameters.
2. Choose values ​​in shared register.
3. Check case, spelling and absence of duplicates.
4. Preserve identifiers from automatic marking if necessary.
5. Test the final link from the intended medium, particularly on mobile.
6. Check campaign data after processing.
7. Keep the published link to facilitate subsequent checks.

Common errors and limitations

Reserve UTM for acquisition links rather than links between your own pages. To measure an internal promotion, plan for dedicated tracking: adding a new campaign source can disrupt attribution, as the Google documentation on reach illustrates. Don't fix an old link in the registry assuming that historical data will be rewritten.

A link can also be transferred to someone else: its parameters then always describe the original campaign, not necessarily the last intermediary. Finally, Google prohibits identifying information in campaign settings. Do not include an email address, telephone number or recipient name. A UTM does not exempt you from checking the rules applicable to your collection.

Frequently asked questions

Should we add UTM to all links?

No. Mark the external links whose campaigns you want to distinguish, when appropriate for the device. Avoid tagging internal navigation links and duplicating existing tracking.

Why do support clicks differ from measured visits?

A click and a session are not the same unit. Also check the actual arrival, redirections and collection conditions. A deviation is not enough to conclude that the UTM are defective.

Do UTM show that a campaign is profitable?

No. They help identify a campaign in the collected data. Profitability requires costs, reliable commercial results and an explicit definition of the chosen scope.

Next step

Take the links from a future campaign, set their convention and have the final version tested by another person. Then keep this template in the register to avoid improvised re-entries.

Sources and resources

• Google Analytics: UTM parameters and URL creation tools.
• MDN: manipulate parameters with URLSearchParams.
• Google Analytics: manual and automatic marking.
• Google Analytics: Traffic source scopes.
• Google Analytics: protection of identifying information.