Introduction

Knowing precisely where your website visitors come from gives you the insights needed to make smarter marketing decisions and get the most from your budget. One of the most powerful tools at your disposal for tracking the effectiveness of your campaigns are UTM parameters.

If you’ve ever wondered why some of your marketing campaigns seem to perform better than others, or if you’re struggling to attribute conversions to specific marketing channels, UTM parameters might be the solution you’re looking for.

In this comprehensive guide, we’ll explore what UTM parameters are, why they’re important, how they map to Google Analytics 4 (GA4) reports, and how you can use them to gain valuable insights into your marketing performance.

What Are UTM Parameters?

UTM (Urchin Tracking Module) parameters are snippets of text added to the end of URLs that help identify the source of your traffic more precisely. These parameters provide additional context about where users came from before landing on your site, allowing you to track the effectiveness of your marketing campaigns with greater accuracy.

Think of UTM parameters as the roadmap that guides GA4 in identifying where your website traffic originates. When your team applies consistent naming conventions across all marketing channels, it creates a unified and accurate view of your traffic sources. It’s the equivalent of everyone using the same terminology, streamlining communication and ensuring clarity in reporting.

However, many marketing teams struggle with this consistency. Different team members or external agencies often manage various channels, each with their own tagging practices. For example, a paid search specialist might label campaigns using one convention, while a social media manager uses another. Without alignment, this lack of standardization leads to fragmented attribution data.

When a user clicks on a link containing UTM parameters, these parameters are captured by Google Analytics, enabling you to see detailed information about the traffic source, medium, and campaign that drove the user to your site.

Let’s consider a scenario: 

You’ve been running paid campaigns across Facebook, LinkedIn, and Microsoft Ads for months. Budgets are spent, impressions are high, and clicks look promising. But when it’s time to evaluate ROI, the numbers don’t add up. You’re not sure which campaigns are actually converting, and you’re left guessing where your ad dollars are going.

This is where UTM parameters become essential. By tagging your ad links with UTM parameters, you can track exactly which platform, ad group, or creative is driving traffic to your site and more importantly, which ones are generating real results like purchases, signups, or booked calls.

Without UTM tracking, you’re flying blind. Maybe your Facebook campaigns are eating up 60% of your budget but producing mostly unqualified traffic.

LinkedIn clicks may cost more, but they might be bringing in leads that actually convert. Microsoft Ads might be driving cheap traffic that never sticks. If you’re not tracking performance at the source, you’re likely wasting thousands on underperforming campaigns and missing chances to double down on what works.

With proper UTM tagging, you get clarity. You can pinpoint that one Facebook ad that brings in high-value leads, or see that educational webinars promoted on Microsoft Ads result in higher conversion rates than flashy promo offers on LinkedIn. It’s the difference between spending blindly and investing wisely.

The Three Core UTM Parameters Explained

There are three primary UTM parameters that you should always include in your URLs to track your campaigns effectively:

1. utm_source

Purpose: Identifies the referrer or source of your traffic.

Examples:

• utm_source=newsletter (for email newsletter traffic)
• utm_source=facebook (for Facebook traffic)
• utm_source=instagram (for Instagram traffic)
• utm_source=google (for Google traffic)

2. utm_medium

Purpose: Identifies the marketing medium or channel.

Examples:

• utm_medium=email (for email marketing)
• utm_medium=cpc (for paid search campaigns)
• utm_medium=social (for organic social media)
• utm_medium=banner (for display advertising)

3. utm_campaign

Purpose: Identifies the specific marketing campaign.

Examples:

• utm_campaign=spring_sale (for a spring sales promotion)
• utm_campaign=product_launch (for a new product launch)
• utm_campaign=black_friday (for Black Friday promotions)
• utm_campaign=christmas_sale (for Christmas sale)

For information on additional UTM parameters like utm_term and utm_content, you can refer to Google’s official documentation:

How to Create UTM Parameters?

Creating URLs with UTM parameters can be done manually, but Google provides a tool called the Campaign URL Builder that makes the process easier.

Using Google’s Campaign URL Builder

1. Go to Google’s Campaign URL Builder: https://ga-dev-tools.google/campaign-url-builder/
2. Enter your website URL in the “Website URL” field.
3. Fill in the required UTM parameters (source, medium, campaign) and any optional parameters you want to track.
4. The tool will generate your tagged URL, which you can then use in your marketing campaigns.

Best Practices for Creating UTM Parameters

When creating UTM parameters, consistency is key. Here are some best practices to follow:

Use a consistent naming convention: Decide on a naming convention for your UTM parameters and stick to it across all campaigns. For example, always use “email” for utm_medium when tracking email campaigns, not “e-mail” or “newsletter” or “edm”.

Use lowercase for all parameter values: UTM parameters are case-sensitive, so “Email” and “email” would be tracked as different sources in Google Analytics. To avoid confusion, use lowercase for all parameter values.

Avoid spaces in parameter values: Instead of spaces, use underscores (_) or hyphens (-). For example, use “summer_sale” instead of “summer sale”.

Be descriptive but concise: Your parameter values should be descriptive enough to understand what they represent, but not so long that they make your URLs unreadable.

Document your UTM strategy: Create a spreadsheet or document that outlines your UTM parameter naming conventions for future reference and to ensure consistency across your team.

By following these best practices, you’ll ensure that your UTM data is clean, consistent, and valuable for analysis.

UTM Parameters in Google Analytics 4

Now that we understand what UTM parameters are and how to create them, let’s explore how they are represented in Google Analytics 4 reports.

In Google Analytics 4, the way UTM parameters are represented differs between Traffic Acquisition and User Acquisition reports. 

When analyzing your campaign performance in GA4, you need to look for different dimension names depending on which report you’re viewing:

Traffic Acquisition reports focus on individual sessions and show how each session arrived at your website, providing a session-level view of traffic sources.

User Acquisition reports, on the other hand, focus on new users and attribute their acquisition to the first source that brought them to your site, giving you a user-centric perspective of how people initially discovered your website.

If you want to see your implemented UTM parameters in User Acquisition reports, you need to use dimensions with “First user” prefixes (like “First user source,” “First user medium,” etc.), as these reports track the original acquisition source for each user.

If you need to check your UTM parameters in Traffic Acquisition reports, you should use the standard session-level dimensions (like “Session source,” “Session medium,” etc.), since these reports analyze each individual session regardless of whether it’s a new or returning user.

In GA4, UTM parameters map to different dimension names depending on whether you’re looking at Traffic Acquisition reports or User Acquisition reports, and all mapping is shown in the table below.

UTM Parameter	Traffic Acquisition Dimension	User Acquisition Dimension
utm_source	Session source	First user source
utm_medium	Session medium	First user medium
utm_campaign	Session campaign	First user campaign
utm_term	Session manual term	First user manual term
utm_content	Session manual ad content	First user manual ad content
utm_id	Session campaign ID	First user campaign ID

If you’re in the Traffic Acquisition report and want to analyze utm_source data, look for the “Session source” dimension. Similarly, to check which utm_campaign is driving traffic, use the “Session campaign” dimension.

Conversely, when you’re in the User Acquisition report and want to determine which utm_medium brought new users to your site, you should search for the “First user medium” dimension. To understand which utm_campaign is acquiring new users, look for “First user campaign.”

This naming convention follows a simple pattern:

• In Traffic Acquisition: UTM parameters are prefixed with “Session”
• In User Acquisition: UTM parameters are prefixed with “First user”

Understanding this distinction allows you to accurately track and analyze the performance of your campaigns across different acquisition reports in GA4.

Accessing UTM Data in GA4 Traffic Acquisition Reports

Step-by-Step Access to Traffic Acquisition Reports

1. Log in to your Google Analytics 4 property.
2. In the left navigation menu, click on “Reports.”

When you first access the Traffic Acquisition report, you’ll see a graph showing the number of sessions over time, followed by a table that breaks down your traffic by default channel grouping. This gives you a high-level overview of which channels are driving traffic to your site.

However, to dive deeper into your UTM data, you’ll need to modify the report to show the specific UTM parameters you’re interested in.

To view your UTM parameter data in the Traffic Acquisition report:

1. Click on the + to add new dimension, or arrow down to expand list

1. You can select dimensions that map to your UTM parameters:
   • “Session source” for utm_source
   • “Session medium” for utm_medium
   • “Session campaign” for utm_campaign
   • “Session source / medium” for a combination view

For example, if you select “Session campaign” from the dropdown, the table will update to show your traffic broken down by campaign name (the value of your utm_campaign parameter).

This allows you to see which specific campaigns are driving the most traffic to your site.

You can then analyze various metrics for each campaign, such as:

• Sessions: The total number of sessions that came from each campaign
• Engaged sessions: Sessions that lasted longer than 10 seconds, had 2 or more page views, or had a conversion event
• Engagement rate: The percentage of sessions that were engaged sessions
• Key events: The number of conversion events that occurred during sessions from each campaign

The “Unassigned” Traffic Problem and How to Fix It

One of the most frustrating issues when working with UTM parameters in Google Analytics 4 is the appearance of significant “Unassigned” traffic in your acquisition reports.

This category often represents a portion of traffic that should be properly attributed to your marketing efforts but isn’t, leading to incomplete data and potentially misguided marketing decisions.

Google Analytics 4 has predefined rules for categorizing traffic into channel groups based on the utm_source and utm_medium parameter values.

If your UTM parameters don’t match these rules, GA4 may not be able to categorize the traffic correctly, resulting in “Unassigned” traffic.

For example, if you use utm_medium=promotion instead of utm_medium=email, GA4 might not recognize this as email traffic and could categorize it as “Unassigned.”

Similarly, if you use inconsistent naming conventions across your campaigns, you might end up with fragmented data that’s difficult to analyze. For instance, if you sometimes use utm_source=facebook and other times use utm_source=fb for your Facebook traffic, GA4 will treat these as two separate sources.

Learn more about unassigned traffic here :

When reviewing your GA4 acquisition data, several warning signs indicate your UTM implementation may be problematic:

1. High Unassigned traffic percentages – When GA4 cannot match your parameters to its channel definitions, traffic gets categorized as “Unassigned.”

2. Unexpected referral traffic spikes – When you’re running campaigns on platforms like Facebook or LinkedIn but see the traffic appearing as simple “referrals” rather than properly attributed campaign traffic, it typically means your UTM parameters are either missing or improperly implemented.

3. Inflated “direct / (none)” traffic – This category should primarily represent users who type your URL directly or use bookmarks. If it’s unusually high, it often indicates missing UTM parameters or situations where no referral is passed.

Frequently Asked Questions

What are UTM parameters, and why should I use them?

UTM parameters are snippets of text added to URLs to track the effectiveness of your marketing campaigns. They help you understand exactly where your website traffic is coming from, which campaigns are most effective, and how users from different sources behave on your site.

Which UTM parameters are required for effective tracking?

The three core UTM parameters that should always be included are utm_source (identifying the referrer), utm_medium (identifying the marketing medium), and utm_campaign (identifying the specific campaign). Additional parameters like utm_term and utm_content are optional but can provide more detailed insights.

How do UTM parameters appear in Google Analytics 4?

In GA4, UTM parameters map to specific dimensions in your reports. For example, utm_source appears as “Session source” in Traffic Acquisition reports and “First user source” in User Acquisition reports. Understanding this mapping is crucial for analyzing your campaign data effectively.

Why is some of my traffic showing as “Unassigned” in GA4 reports?

“Unassigned” traffic occurs when your UTM parameter values don’t align with GA4’s default channel definitions. To avoid this, use standard values for utm_medium (like “email”, “cpc”, “social”) that match GA4’s predefined channel categories and maintain consistency across all your campaigns.

Is there a tool to help me create UTM parameters correctly?

Yes, Google provides the Campaign URL Builder tool (https://ga-dev-tools.google/campaign-url-builder/) that makes it easy to create properly formatted UTM-tagged URLs. Simply enter your website URL and the UTM parameter values, and the tool will generate the complete URL for you to use in your marketing campaigns.