What are UTM parameters?
A UTM parameter is a name and value pair appended to a URL. A question mark introduces the parameters and an ampersand separates them. A link from a newsletter could look like this:
https://www.example.co.uk/offer/?utm_source=newsletter&utm_medium=email&utm_campaign=autumn-sale
The page itself does not change. When it is opened, however, the analytics tool records that the visitor came via the newsletter, by email, as part of the autumn sale. Without this tagging, clicks from email programs, apps or PDF documents frequently cannot be attributed to any source.
The parameters at a glance
According to Google, you should always set at least the first three parameters:
- utm_source: the source, such as newsletter, linkedin or trade-fair-catalogue.
- utm_medium: the medium, such as email, cpc for paid clicks, or social.
- utm_campaign: the campaign, such as autumn-sale or a promo code.
- utm_id: a campaign ID, if you import cost or campaign data later.
- utm_term: the paid keyword in search ads.
- utm_content: distinguishes variants, for example two links in the same email.
- utm_source_platform: the platform through which the traffic is bought or managed.
The parameters utm_creative_format and utm_marketing_tactic also exist, but according to Google they are not reported in GA4 properties.
How GA4 evaluates UTM parameters
In Google Analytics 4, source, medium and campaign populate the dimensions in the traffic acquisition report. GA4 also derives the channel from source and medium, using fixed default channel groups:
- If the medium or source is “email”, the visit is assigned to the Email channel.
- If the visit comes from a search engine and the medium is, for example, “cpc” or “ppc”, it counts as paid search.
- If no rule matches, the visit appears as “Unassigned”.
Two subtleties: the channel rules are not case sensitive, but the reports are. “google” and “Google” appear there as two separate sources. And for Google Ads you usually do not need UTM parameters: auto-tagging appends a click ID (GCLID), and in GA4 its values take priority over manually set parameters.
Typical mistakes and how to avoid them
- Inconsistent spelling: newsletter, Newsletter and news-letter create three sources. Make lower case and hyphens the rule.
- Free values in the medium: a medium such as “mail-autumn” matches no channel rule. Use fixed values such as email, cpc, social or display.
- UTM parameters on internal links: they are meant for links from outside. On your own website they distort the origin of the visit. GA4 has its own events for internal banners.
- Personal data in the URL: email addresses or customer numbers have no place in UTM values. Google prohibits sending such data to Google Analytics.
- Redirects that drop parameters: check that short links and redirects keep the parameters all the way to the landing page.
The simplest solution is a shared spreadsheet in which your team creates and documents all campaign links.
From the campaign to the individual enquiry
GA4 shows how many enquiries a campaign has brought in total. It does not show which specific enquiry is behind them, and that is intentional, because personal data does not belong in Google Analytics.
Our WP Lead Tracker closes this gap. The WordPress plugin captures UTM parameters, referrers and other campaign data and stores every enquiry with source, medium, campaign and time directly in WordPress. Supported forms include Gravity Forms, Contact Form 7, Elementor Forms and WPForms. This lets you see in the back end which campaign an individual enquiry came from and follow its path along the customer journey.
Would you like to tag your campaigns properly and attribute every enquiry to its source? Then get in touch with us or read more about our web analytics!
