Have you ever logged into your Google Analytics account to check on a paid advertising campaign, such as SEM, for your heart rate to immediately elevate when you see large portions of your paid traffic coming from a large city outside of your targeting area? Don’t worry. We all have had this happen at some point, and it is often nothing to worry about.

Wait, why shouldn’t I worry?

Google Analytics is absolutely a reliable source of data and source of truth the vast majority of the time - it acts as a hub for all of your website data, including paid marketing campaigns that drive users to your site. There is no easier option for a central hub to track and mine insights for all of your website visitors; however, there is one area where Google Analytics should not be your be-all-end-all source of truth - location data.

How Google Analytics determines user location

Google Analytics location data is not very granular. The smallest location area it can report on is the city level. While reliable for larger areas such as regions, states, or countries, there often can be discrepancies when evaluating the performance of an ad campaign on smaller geographic areas. Oftentimes, good paid campaigns are targeted by more granular parameters such as city, zip code, county/parish, or even a radius around set coordinates.  

Additional discrepancies between Google Analytics data and your campaign’s targeting area can occur due to how Google Analytics determines a user’s location. Google Analytics uses the user’s IP address of a website hit to determine the user’s location. IP-based location is typically reliable and useful for broader geographic areas such as a state, region, or country. However, it is not as reliable for more granular areas such as cities and anything smaller. Connected IP addresses are also used to only estimate based on third-party geolocation database queries. This means that Google Analytics is taking the IP address and matching against third-party databases of recorded IP addresses and their last recorded location. Additionally, it is very common for IP addresses to be frequently reassigned to different users in different locations, and these third-party databases are not updated nearly as frequently as IP addresses are reassigned. This is true for both Universal Analytics and GA4. Despite the robust changes in data measurement models between GA4 and Universal Analytics, the way they both use data to determine user location is fundamentally the same and still determined solely by IP address at the time of this writing.

So, where do I look for correct data?

When trying to evaluate campaign performance by location, your source of truth should be the ad platform that’s delivering the campaign. Using Google Ads as an example, we can see how much more robust its location targeting and tracking capabilities are compared to Google Analytics. In addition to IP addresses, Google Ads uses GPS data to determine lat/long coordinates, the Wi-Fi location of a connected device, and Cell tower connection locations. Google Ads takes all of these data points into account when determining a user’s location.

How to verify‍

So next time you look at the location reporting in Google Analytics for your paid campaigns, and things don’t quite match your location targeting, don’t panic. To more accurately verify that your campaigns are serving in the appropriate locations, your source of truth should be the ad platform itself. The most accurate location data will be found in the impressions served and clicks location reports or their nearest equivalents.

Sources:

• https://www.jmillermarketing.com/insights/2018/errors-in-google-analytics-user-location-data
• https://support.google.com/google-ads/answer/2453995?hl=en&ref_topic=3119074
• https://support.google.com/analytics/answer/6160484?hl=en#zippy=%2Cin-this-article
• https://www.kolbeco.net/articles/digital/google-analytics-location-accuracy
• https://enveritasgroup.com/campfire/discrepancies-in-location-data-from-analytics-and-adwords/ 
• https://support.google.com/analytics/answer/11598602?hl=en&ref_topic=1008008