[GA4] How traffic source dimensions are updated
Use manual tagging in combination with auto-tagging in some specific cases
For advertisers, auto-tagging unlocks many benefits in Google Analytics. For example, you automatically gain access to new dimensions in your reports and you are able to create more granular audiences based on these additional dimensions. Using auto-tagging is also required to create conversions from your Google Analytics key events in Google Ads, Display & Video 360, Campaign Manager 360 or Search Ads 360.
However, even if auto-tagging is enabled, there are some cases where the Google Click Identifier (GCLID) or DoubleClick Identifier (DCLID) cannot be used as intended. This can happen, for example, when ad_user_data is denied through your Consent Mode implementation. In these situations, the automatic retrieval of dimensions from the advertising platform might not be possible. As a result, you might see (not set) labels for cross-channel traffic source dimensions in Google Analytics.
To improve your traffic source reporting, you can implement manual tagging (UTM parameters) alongside auto-tagging. Manual tagging allows you to send traffic source information to Google Analytics by configuring destination URLs with UTM parameters to populate traffic source dimensions.
When you do this, in instances where the GCLID or DCLID cannot be used as intended, or data is otherwise not available:
- UTM parameters are used to populate cross-channel dimensions in Google Analytics.
- In addition to being used to populate cross-channel dimensions under these circumstances, UTM parameters always populate manual traffic source dimensions.
- Default Channel Group cannot rely on automatic retrieval of dimensions from the advertising platform in instances where Google Analytics is not able to use the GCLID or DCLID as intended. In these cases, Google Analytics leverages UTM values to set Default Channel Group.
- Reports specific to an advertising platform, such as the Google Ads report in the Advertising section, only display traffic in cases where auto-tagging is enabled and the GCLID or DCLID can be used as intended.
- Once you start to implement UTM parameters, you may notice a change in your cross-channel traffic source reporting as Google Analytics begins incorporating the UTM values.
For the best cross-channel reporting experience, we recommend that you enable auto-tagging for linked advertising accounts in addition to populating all relevant UTM parameters with campaign-level data to account for cases where Analytics cannot use the GCLID or DCLID as intended. Once you’ve done so, you should begin seeing improvements in cross-channel traffic source reporting from that point forward.
Best practices for manual tagging
In instances where the GCLID or DCLID cannot be used as intended, if any UTM parameter is present on the URL, Google Analytics will derive all cross-channel traffic source dimension values from UTM parameters, exclusively. Because of this, if you are setting one UTM parameter, we strongly recommend that you set all relevant UTM parameters, especially utm_source, utm_medium, utm_campaign, utm_id, and utm_source_platform. Missing UTM parameters will result in (not set) values being present in reporting.
When adding parameters to a URL, consider the following:
- Each parameter must be paired with a value that you assign.
- Each parameter-value pair contains campaign-related information.
- You can add parameters to a URL in any order.
- You must list the parameters and values as pairs, separated by an equal sign.
- You must separate the parameters from the URI with a question mark.
- You must separate each parameter-value pair with an ampersand.
- Parameter values are case sensitive. For example, utm_source=google is different from utm_source=Google.
- Special characters in parameter values must be URL encoded. For example, you would pass the value "Google Ads" for source platform as utm_source_platform=Google+Ads.
When manually tagging traffic from Google’s advertising platforms, we recommend setting UTM parameter values as follows:
| Advertising platform | Source | Medium | Campaign | Campaign ID | Source platform1 |
|---|---|---|---|---|---|
| utm_source | utm_medium | utm_campaign | utm_id | utm_source_platform | |
| Google Ads | "google" | "cpc" | <Google Ads campaign name> | <Google Ads campaign ID> |
"Google+Ads"" Note: ‘+’ character included above assumes that this value is passed in a URL. |
| Search Ads 360 |
Configured at the SA360 engine account level, based on the type of engine account2 |
"cpc" |
<Search Ads 360 campaign name> |
<Search Ads 360 campaign ID> |
"SA360" |
| Display & Video 3603 |
<Top-level URL or app name where the ad served> |
"cpm" |
<Display & Video 360 campaign name> |
<Display & Video 360 campaign ID> |
"DV360" |
| Campaign Manager 360 |
<Top-level URL or app name where the ad served> |
"cpm" |
<Campaign Manager 360 campaign name> |
<Campaign Manager 360 campaign ID> |
"CM360" |
1 At present, even if you set utm_source_platform as recommended, cross-channel reports in Google Analytics will continue to show the "Manual" value for the source platform dimension. In the future, the source platform dimension will begin reporting values passed via the utm_source_platform parameter.
2 Examples:
- Google Ads: "google"
- Microsoft Ads: "bing"
- Yahoo! Japan: "yahoo.jp"
- Baidu: "baidu"
- Facebook: "facebook"
- Twitter: "twitter"
- Yahoo! Gemini: "yahoo gemini"
- Other engine track accounts: "engine track"
- Other engines: "other engines"
3 We generally recommend implementing manual tagging in the ad server. In the case of DV360 traffic served via CM360, we recommend implementing manual tagging in CM360 and setting source platform = DV360. Additionally, if you're running a DV360 campaign on Youtube, the source should be "youtube".