Key takeaways
- UTM parameters are tags added to the end of a link, such as ?utm_source=newsletter, that tell Google Analytics where a visit came from.
- Google says you should always use utm_source, utm_medium and utm_campaign. utm_content and utm_term are optional and help you compare versions of a link.
- Values are case sensitive, so Email and email show up as two different sources. Agree on lowercase names and write them down.
- Missing parameters show as (not set) in reports. Campaign data appears in GA4’s Traffic acquisition report.
- Tag links you share outside your website: emails, social posts, bios, QR codes and partner links. Leave links between your own pages untagged.
What are UTM parameters?
A UTM parameter is a short tag added to the end of a link. When someone clicks the link, Google Analytics reads the tag and records where the visit came from. Without it, many visits from emails, apps and social bios land in Direct or Referral, and you cannot tell which campaign worked.
A tagged link looks like this:
https://www.example.com/?utm_source=newsletter&utm_medium=email&utm_campaign=spring-offer
The parameters you need
Google’s UTM parameters page lists several. These five cover almost every small business:
- utm_source: where the traffic came from, such as instagram, newsletter or partner-site.
- utm_medium: the type of channel, such as email, social, cpc or qr.
- utm_campaign: the campaign name, such as spring-offer or webinar-march.
- utm_content: optional. Tells apart two links in the same campaign, such as header-button and footer-link.
- utm_term: optional. Mostly used for paid search keywords.
Google says you should always use utm_source, utm_medium and utm_campaign. If a parameter is missing, reports show it as (not set).
A naming system that keeps reports clean
Google notes that UTM values are case sensitive. Facebook, facebook and FB will appear as three different sources. Most messy reports come from this. Set a few rules and share them with anyone who creates links:
- Use lowercase only.
- Use hyphens between words, no spaces.
- Keep one fixed list of sources and mediums.
- Name campaigns with the offer or month, such as spring-offer or 2026-11-newsletter.
- Keep a shared sheet of every tagged link you create.
Match your mediums to GA4 channels
GA4 sorts visits into a default channel group such as Email, Organic Social, Paid Social and Referral, using your source and medium values. Use plain, common mediums like email, social and cpc, so visits land in the channel you expect. Custom words can end up in a catch-all group.
Examples
- Instagram bio:
?utm_source=instagram&utm_medium=social&utm_campaign=bio - Monthly newsletter:
?utm_source=newsletter&utm_medium=email&utm_campaign=2026-11-newsletter - QR code on a flyer:
?utm_source=flyer&utm_medium=qr&utm_campaign=fall-open-house - Two buttons in one email: add
&utm_content=top-buttonand&utm_content=bottom-linkto tell them apart.
What to tag and what to leave alone
Tag links you share outside your website: emails, social posts and bios, QR codes, partner and directory listings, and podcast show notes. Google Ads can track its own clicks automatically, so check your ad platform’s settings before adding tags by hand.
Do not add UTM tags to links between pages on your own website. A tagged internal link starts a new campaign record and hides where the visitor first came from.
How to build and check tagged links
- Use Google’s free Campaign URL Builder or type the tags by hand.
- Shorten long links if you need to, but test that the tags survive the redirect.
- Click the link and check GA4’s Realtime report to confirm the visit shows the right source and medium.
- After the campaign runs, open the Traffic acquisition report and filter by session campaign.
Connect it to real leads
UTMs tell you which campaign brought a visit. To know which campaign brought a customer, record the source on every lead in your CRM and mark form submissions as key events in GA4. Our GA4 guide explains key events, and SET OS records the page each website lead was sent from.
Where to get help
We set up tracking, naming rules and reporting as part of our analytics and reporting work.