How to fix the “(not set)” issue in Google Analytics 4

Introduction

If you’ve ever looked at your Google Analytics reports and seen the “(not set)” placeholder instead of the information you expected, you know how frustrating it can be. Missing data obscures insights and makes it challenging to accurately assess campaign performance and user behavior. This article will walk you through practical steps to diagnose and fix the “(not set)” issue in your GA4 reports, ensuring your data is complete and actionable.

Main steps to fix “(not set)” in google analytics

1. Audit and correct your tracking code

Why it matters:
If your tracking code isn’t installed on every page or fires too late, key events like the initial page_view might be missed—resulting in “(not set)” values for dimensions such as landing page or page title.

What to do:

• Verify installation:
  • Open a few pages of your website in a browser and use the “View page source” option (or a tool like Google Tag Assistant) to ensure your GA4 Measurement ID (e.g., “G-XXXXXXXXXX”) is present on every page.
• For single-page applications (SPAs):
  • Configure your website or use Google Tag Manager (GTM) to trigger a new page_view event every time a URL or view changes. This ensures that data isn’t lost when users navigate without a full page reload.

2. Standardize and verify utm parameter tagging

Why it matters:
Improperly tagged URLs mean that GA4 might not recognize the source, medium, or campaign behind a session, which will result in “(not set)” entries in your reports.

What to do:

• Use the campaign URL builder:
  • Visit Google’s Campaign URL Builder and create URLs with correct UTM parameters (utm_source, utm_medium, utm_campaign).
• Audit existing links:
  • Review all your marketing materials and ensure that every campaign URL is consistently tagged. Maintain a spreadsheet of these URLs so you can catch any discrepancies before they affect your analytics.

3. Adjust session timeout settings

Why it matters:
When a visitor leaves a page open and returns after the session has expired, a new interaction might not trigger the page_view event, leading to gaps in your landing page data.

What to do:

• Change session timeout in GA4:
  1. Log in to your GA4 property and click on Admin.
  2. Under the Property column, click on Data Streams and select your web data stream.
  3. Click on Configure tag settings, then select Show all.
  4. Find and click Adjust session timeout. Increase the timeout duration to better match your user behavior (you can extend it up to 7 hours and 55 minutes).

4. Ensure proper google ads integration

Why it matters:
Unlinked or improperly tagged Google Ads campaigns will result in ad-related dimensions displaying “(not set),” making it hard to measure your ad performance.

What to do:

• Link google ads and GA4:
  • In GA4, navigate to Admin → Product Links → Google Ads Links and verify that your accounts are properly linked.
• Enable auto-tagging:
  • Log in to your Google Ads account, click the tools icon, and under Account Settings, confirm that auto-tagging is enabled. This ensures that the GCLID (Google Click Identifier) is appended automatically to your URLs, improving data attribution.

5. Review custom dimensions and content groups

Why it matters:
Custom dimensions and content groups that are misconfigured in GTM can fall back to “(not set)” if their values aren’t captured correctly.

What to do:

• Check GTM configurations:
  • Open your GTM container and review tags sending custom dimensions. Confirm that the parameter names exactly match the definitions in GA4 (remember, they’re case-sensitive).
• Audit the data layer:
  • Ensure that your custom values are pushed to the data layer before the GA4 tag fires. This guarantees that GA4 receives the correct data without defaulting to “(not set).”

6. Use debugging tools to validate changes

Why it matters:
Monitoring your site’s real-time activity helps catch any issues immediately so you can refine your tracking setup.

What to do:

• Employ tools like Google Tag Assistant or GA Debug View:
  • Use these tools to watch events as they fire on your site. Verify that the page_view event fires first and that all parameters (including UTM tags and custom dimensions) are present.
• Check for errors:
  • Identify any events missing key information and adjust your configuration accordingly.

Conclusion

Addressing the “(not set)” issue in Google Analytics doesn’t have to be a guessing game. By following these practical, step-by-step methods—auditing your tracking code, standardizing UTM tagging, adjusting session settings, properly integrating Google Ads, and fine-tuning custom dimensions—you can significantly reduce data gaps and improve your reporting accuracy. With complete and accurate data, you’ll be better equipped to make data-driven decisions that drive your business forward.