UTM Parameters.

What are UTM parameters?

UTM parameters are short tags added to the end of a link that tell analytics tools such as GA4 where a visitor came from. A tagged link might end ?utm_source=newsletter&utm_medium=email&utm_campaign=autumn-offer. When someone clicks, GA4 reads the tags and files the visit under that source, medium and campaign.

The five most common tags are utm_source, utm_medium, utm_campaign, utm_term and utm_content.

Why it matters

Without UTM tags, visits from your email newsletter, a LinkedIn post, a QR code on a van or a partner's website can end up lumped together as direct or referral traffic, and you cannot tell which activity brought the enquiries. With them, every campaign can be measured in the same report. That is the difference between knowing the printed brochure produced enquiries and assuming it did nothing.

The parts that matter

• utm_source Where the click came from, such as linkedin, newsletter or a partner's site name.
• utm_medium The type of channel, such as email, social, cpc or qr. GA4 uses it to group traffic into channels, so consistency matters.
• utm_campaign The specific campaign or offer, such as spring-boiler-service.
• utm_term and utm_content Optional extras for telling apart keywords, ad versions or two links in the same email.
• Google Ads auto-tagging Google Ads tags its own clicks automatically, so UTMs matter most for every other channel.

What to do about it

Create a one-page naming convention: lower case only, a fixed list of sources and mediums, and a pattern for campaign names. Keep a shared spreadsheet that builds tagged links, so nobody types them by hand. Tag every link you control outside Google Ads: emails, social posts, partner links and QR codes on print. Never add UTMs to links between pages on your own site. A week later, check GA4's traffic acquisition report to confirm the tags are landing.