The difference between UTM source, medium, and campaign is simple: Source tells you where the traffic came from, Medium tells you how it arrived, and Campaign tells you why—which specific initiative the click belongs to. Together, these three required parameters form the foundation of campaign tracking, helping you understand exactly which marketing efforts drive traffic and conversions .
TL;DR
- UTM parameters are tags added to URLs that tell analytics tools where traffic came from and why .
- utm_source identifies the specific platform or referrer (e.g., facebook, google, newsletter) .
- utm_medium identifies the marketing channel or vehicle (e.g., social, email, cpc) .
- utm_campaign identifies the specific campaign name (e.g., summer_sale_2025) .
- Use all three together for complete attribution—they answer where, how, and why someone clicked your link .
Key Takeaways
- Source and medium work together as a hierarchy. Medium is the high-level channel (e.g., email), while Source is the specific subchannel (e.g., monthly_newsletter). Medium answers “how” and Source answers “where” .
- Consistent naming prevents data fragmentation. Use lowercase values and stick to a naming convention across your team so that facebook and Facebook don’t appear as separate sources in your reports .
- Campaign names should be descriptive and unique. Avoid punctuation and spaces; use underscores instead. For example, spring_launch_2025 works better than Spring Launch 2025 .
- UTM parameters are not the only tracking option. They map to fields in Google Analytics and other analytics platforms, but platforms like Google Ads also offer auto-tagging with GCLID parameters that work differently .
What Are UTM Parameters?
UTM stands for Urchin Tracking Module—a name inherited from Urchin Software, which Google acquired in 2005 to build Google Analytics . UTM parameters are small text snippets added to the end of a URL that pass information to analytics platforms like Google Analytics .
Without UTM parameters, analytics tools rely on referrer data, which is often too vague. For example, traffic from a paid Facebook ad, an organic Facebook post, and a shared link might all appear grouped together as “social” traffic . UTM parameters let you define each link’s source, medium, and purpose yourself, giving you precise, actionable data .
A tagged URL follows this basic structure :
The base URL is followed by a ?, then each parameter is separated by & .
UTM Source: Where Is the Traffic Coming From?
The utm_source parameter identifies the specific platform, publisher, or referrer that sent the traffic .
Common examples:
- facebook, instagram, linkedin (for social platforms)
- google, bing, yahoo (for search engines)
- monthly_newsletter, welcome_email (for email sources)
Key principle: Source answers the question “Where is this person coming from?” . It should identify the platform where your ad, post, or link appeared—not the ad type or the content. For example, if you’re running a campaign on Facebook, the source is facebook, not retargeting or sponsored .
UTM Medium: How Is the Traffic Arriving?
The utm_medium parameter identifies the marketing vehicle or channel through which the traffic arrived .
Common examples:
- social (for social media traffic)
- email (for email campaigns)
- cpc (for paid search or paid social ads)
- organic (for natural search results)
- referral (for traffic from other websites)
Key principle: Medium answers the question “How are they getting to you?” . It represents the highest-level channel. If you’re sending traffic through an email campaign, the medium is email, not the specific email list or the action .
Think of Medium as the category and Source as the specific instance within that category. For example, if your Medium is social, your Source could be facebook or instagram .
UTM Campaign: Why Is This Traffic Coming?
The utm_campaign parameter identifies the specific marketing campaign or initiative that the link belongs to .
Common examples:
- spring_sale_2025
- product_launch_q3
- black_friday_promo
- retargeting_audience_a
Key principle: Campaign answers the question “Why are they coming to you?” or “What initiative is this part of?” . It allows you to group all links related to a single campaign, regardless of how many channels or platforms you use .
Best practice for campaign naming: Avoid punctuation and empty spaces—they can cause browser encoding errors. Use underscores instead, like summer_sale_2025 . Keep names consistent across your team so you can easily filter and compare campaign data later .
How Source, Medium, and Campaign Work Together
These three parameters form a complete picture when used together:
| Parameter | Question It Answers | Example Value |
|---|---|---|
| utm_source | Where? | |
| utm_medium | How? | social |
| utm_campaign | Why? | spring_sale |
Together, they tell a complete story: “This click came from Facebook (source), through a social media post (medium), as part of our spring sale campaign (campaign)” .
When you view this data in Google Analytics, these parameters map directly to dimensions like Source/Medium and Campaign, making it easy to build reports that compare performance across channels and initiatives .
Optional Parameters: Content and Term
While Source, Medium, and Campaign are required for effective tracking, two additional parameters offer extra flexibility :
utm_content – Helps distinguish between different versions of a link within the same campaign. Useful for A/B testing ad creative, email copy, or button text. For example, blue_banner vs red_banner .
utm_term – Used primarily for paid search campaigns to track specific keywords. For example, if you’re bidding on running+shoes, you can track that keyword’s performance .
Common Mistakes to Avoid
Mistake 1: Using inconsistent naming. If you use Facebook on one link and facebook on another, they’ll appear as separate sources in your reports. Stick to lowercase and agree on a standard naming convention .
Mistake 2: Confusing Source and Medium. Source is the platform (e.g., google), Medium is the channel type (e.g., cpc). Don’t use “Google Ads” as a Medium—use cpc and put google in the Source field .
Mistake 3: Using punctuation or spaces in campaign names. These can cause encoding errors. Use underscores instead .
Mistake 4: Not testing links before deployment. Always click your tagged links to confirm they redirect correctly and the parameters are preserved .
Frequently Asked Questions
What is the difference between UTM source and medium?
UTM source identifies the specific platform or referrer (where the traffic came from), while UTM medium identifies the marketing channel or vehicle (how the traffic arrived). For example, source might be facebook and medium might be social .
Do I need to use all three parameters?
Yes. Source, Medium, and Campaign are the core required UTM parameters for effective campaign tracking. Without all three, your data will be incomplete .
Are UTM parameters case-sensitive?
Yes, UTM parameters are case-sensitive. Facebook and facebook will appear as separate entries in your analytics reports. Always use lowercase for consistency .
Can I use UTM parameters with shortened URLs?
Yes. Many link management platforms and URL shorteners let you add UTM parameters to your shortened links. The parameters remain attached to the link and pass through to your analytics tool when clicked .
How do I create a UTM-tagged link?
You can add UTM parameters manually to your URL, use a free UTM builder tool like Google’s Campaign URL Builder, or use a link management platform with built-in UTM fields .
What happens if I use spaces in a campaign name?
Spaces can cause browser encoding errors. Use underscores (e.g., spring_sale) instead of spaces for cleaner, more reliable tracking .
Where can I see UTM data in Google Analytics?
In GA4, navigate to Reports > Acquisition > Traffic acquisition. You can add Campaign and Source/Medium as dimensions to see your UTM data broken down .
Sources
- Adobe Marketo Measure: UTM Parameters Documentation
- Click Consult: Adding UTM Tracking to Your Social DNA
- UTM.io: What Is a UTM?
- Rebrandly: UTM Links Explained
- Google Analytics Blog: Getting Started with Campaign Measurement
Have a UTM tracking challenge you’re trying to solve? Share your question in the comments—we might cover it in a future deep dive.
