Analytics Reference
UTM Parameter Reference
UTM tagging is the cheapest attribution work available and the most frequently botched. The parameters themselves take five minutes to learn. The discipline is in the naming convention, which is what this page is really about.
| Parameter | Required | Purpose | Example value |
|---|---|---|---|
| utm_source | Yes | Where the traffic came from | |
| utm_medium | Yes | The marketing channel type | cpc |
| utm_campaign | Yes in practice | The specific campaign | q4-launch |
| utm_term | No | Paid search keyword | marketing-agency |
| utm_content | No | Creative or link variant | hero-cta-b |
| Medium value | Channel it maps to |
|---|---|
| cpc, ppc, paidsearch | Paid Search |
| organic | Organic Search |
| social, paid-social | Organic Social or Paid Social |
| referral | Referral |
| display, banner | Display |
| affiliate | Affiliate |
| Mistake | Consequence |
|---|---|
| Mixed capitalisation | Facebook and facebook become separate sources |
| Tagging internal links | Overwrites the original session source |
| Spaces in values | Encoded as %20 and splits reporting |
| Inventing medium values | Traffic lands in Unassigned |
| Tagging paid search manually with auto tagging on | Conflicting data between platforms |
Notes
Pick a convention and enforce it with a spreadsheet or a builder tool, not with memory. Lowercase everything, use hyphens instead of spaces or underscores, and keep a controlled vocabulary of source and medium values. The cost of inconsistency is not visible on day one, it is visible six months later when the report has forty variants of the same campaign.
Never put UTM parameters on internal links. A UTM on a link between two pages of your own site starts a new session attribution in most tools and reassigns the conversion away from the real acquisition source. Use event tracking for internal link measurement instead.
Medium is the field that drives channel grouping, so treat it as a closed list rather than free text. Source can be more permissive because it names a specific property, but medium should only ever take one of the values your analytics platform recognises.
For Google Ads, leave auto tagging on and do not add manual UTMs. The gclid parameter carries richer data than UTMs can, and mixing the two causes conflicting numbers between Google Ads and GA4. Google's campaign URL documentation covers the interaction.
Frequently asked questions
Are UTM parameters case sensitive?
Yes. Email and email are recorded as two different mediums in most analytics tools. Standardise on lowercase everywhere.
Do UTM parameters hurt SEO?
They create duplicate URLs, which is why the canonical tag matters. With a correct canonical pointing at the clean URL, tagged links are not an SEO problem.
Should I use utm_term for anything other than paid search?
You can, but it is conventional to reserve it for keywords. If you need another dimension, utm_content is the more flexible field.
Official sources
Platforms change specifications without notice. Check the primary documentation before a launch that depends on an exact value.
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