Until now, different campaign formats originating from Microsoft Advertising were often grouped under a broader paid search structure within analytics platforms. This created limited measurement visibility, particularly for advertisers who wanted to analyse the performance of Search, Audience Ads, Shopping Ads, Video Ads, and Performance Max campaigns separately.
With the new structure, Microsoft Advertising will begin sending UTM parameters in a more granular way based on campaign format. As a result, Microsoft Advertising traffic may be reported in GA4 and similar analytics platforms under channel groups that better reflect the relevant campaign type, rather than appearing solely under a single paid search category.
This update should not be considered merely a technical change to URL parameters. Its main impact will be visible in reporting, budget allocation, channel performance analysis, dashboard structures, CRM source matching, and historical period comparisons.
What Is Microsoft Advertising UTM Auto-Tagging?
UTM auto-tagging is a feature that automatically adds UTM parameters to landing page URLs when users click on an advertisement. These parameters help identify which advertising source, campaign, ad group, or keyword brought the user to the website.
The existing Microsoft Advertising auto-tagging structure generally uses the following parameters:
| UTM Parameter | Meaning |
|---|---|
| utm_source | The source from which the traffic originated |
| utm_medium | The channel or advertising model that generated the traffic |
| utm_campaign | Campaign information |
| utm_content | Ad group or content information |
| utm_term | Keyword or product group information |
This structure is used to analyse campaign performance across reporting platforms such as Google Analytics, Adobe Analytics, HubSpot, CRM systems, attribution tools, and Looker Studio.
However, the most significant limitation of the current structure was that different Microsoft Advertising campaign formats were not sufficiently differentiated within analytics platforms. For example, although Search campaigns, Shopping campaigns, and Audience Ads campaigns have different user behaviours, cost models, and optimisation approaches, they could appear under the same or similar channels within analytics reports.
What Is Changing on September 2, 2026?
Starting on September 2, 2026, Microsoft Advertising will begin applying format-specific UTM values to accounts that use UTM auto-tagging. This change will be activated automatically for advertisers who already use UTM auto-tagging. In other words, no manual action is expected to be required within the relevant accounts.
The primary purpose of the new structure is to enable Microsoft Advertising campaign types to be classified more accurately within third-party analytics platforms.
Based on the information shared in the announcement, the new structure is generally expected to work as follows:
| Campaign Format | New UTM Structure | Expected Analytics Impact |
|---|---|---|
| Search Ads | utm_source=bing, utm_medium=cpc | Traffic will continue to be reported under Paid Search. |
| Audience Ads | utm_source=msads, utm_medium=cpm | Traffic is expected to be classified more appropriately under Display. |
| Shopping Ads | utm_source=msads, utm_medium=cpc, with shopping included in the campaign suffix | Traffic is expected to be separated under Paid Shopping. |
| Video Ads | utm_source=bingvideo, utm_medium=cpc | Traffic is intended to be separated under Paid Video. |
| Performance Max | utm_source=msads, utm_medium=cross-network, with cross-network included in the campaign suffix | Traffic is intended to be separated under Cross-network. |
The important point here is that these values are not merely technical parameters displayed in the URL. They may directly affect the channel grouping logic used by platforms such as GA4. In particular, utm_medium, utm_source, and utm_campaign values can influence whether traffic appears under Paid Search, Display, Paid Shopping, Paid Video, or Cross-network.
Why Is This Change Important?
The most significant impact of this change is that Microsoft Advertising traffic will be separated into more accurate channel groups. Particularly for brands that evaluate multiple advertising formats within the same report, this change may enable healthier and more informed performance decisions.
For example, Audience Ads and Search Ads do not represent the same level of user intent. In a Search campaign, the user actively performs a search and the advertisement is triggered based on that search intent. With Audience Ads, however, the user is generally exposed to the advertisement through targeting signals, interests, or placements. Evaluating these two campaign types within the same paid search category may lead to incorrect interpretations of channel performance.
Similarly, Shopping Ads operate differently from traditional Search campaigns. Factors such as product listings, product feeds, prices, stock status, visuals, and product titles play a decisive role in Shopping performance. As a result, mixing Shopping traffic with Paid Search can make product-level advertising performance more difficult to analyse.
The issue becomes even more important for Performance Max. Because Performance Max campaigns can operate across multiple advertising inventories, evaluating this traffic under Cross-network provides a classification that is more consistent with the nature of the campaign.
What May Change in GA4 Reports?
One of the most visible changes following this update will appear in GA4 acquisition reports. The channel distribution of Microsoft Advertising traffic may change, particularly within the Traffic acquisition, User acquisition, Advertising, and Explorations reports.
Some traffic that previously appeared under Paid Search may be separated into different channel groups after September 2, 2026:
- Audience Ads traffic may begin appearing under Display.
- Shopping Ads traffic may be separated under Paid Shopping.
- Video campaigns may be reported under Paid Video.
- Microsoft Performance Max traffic may appear under Cross-network.
- Search Ads traffic may continue to appear under Paid Search.
For this reason, a decline in Paid Search traffic after September 2, 2026, may not always represent a genuine loss in performance. Similarly, an increase in Display, Paid Shopping, Paid Video, or Cross-network should not automatically be interpreted as a new investment in those channels.
This change may create a structural reporting break caused by updated channel grouping logic.
What Should Be Considered in Reporting and Dashboards?
This update requires additional checks, particularly for teams using Looker Studio, GA4 Explorations, BigQuery, CRM reports, and manually prepared performance tables.
First, the filters currently used to identify Microsoft Advertising traffic within dashboards should be reviewed. If reports rely only on the following filters, some traffic may be excluded after September 2:
source = bing
medium = cpc
This filter structure may no longer be sufficient to capture all Microsoft Advertising traffic. Audience Ads may use msads as the source and cpm as the medium. Performance Max may use cross-network as the medium. Shopping and Video campaigns may also generate different source, medium, or campaign suffix values.
For this reason, dashboards may need a more comprehensive structure that uses campaign names, campaign suffixes, source platform values, landing page query parameters, and custom channel groups rather than relying solely on source and medium.
What Should BigQuery and Looker Studio Users Do?
Teams using the GA4 export in BigQuery should separately review session source, session medium, campaign, default channel group, and landing page query parameters.
Custom SQL queries should be updated if they include CASE WHEN structures such as:
WHEN source = 'bing' AND medium = 'cpc' THEN 'Microsoft Ads'
This structure may become incomplete under the new system. More comprehensive logic should evaluate values such as bing, msads, bingvideo, cross-network, and shopping. However, a final classification should not be implemented until the update goes live and the actual click URLs and GA4 values have been tested.
In Looker Studio, blended data sources, channel filters, paid media filters, and custom Microsoft Ads segments should be reviewed. If reports treat only Paid Search as Microsoft Advertising performance, sudden reporting breaks may occur after September 2.
How May CRM and Lead Sources Be Affected?
This update is also important for brands that capture UTM values through hidden fields in CRM systems. If forms collect utm_source, utm_medium, utm_campaign, utm_content, and utm_term values, the new source and medium values may affect CRM reporting.
For example, Microsoft Advertising leads that were previously recorded mostly as bing / cpc may begin appearing under different combinations such as msads / cpm, msads / cpc, or msads / cross-network.
This may create the following effects in CRM systems:
- The number of Microsoft Advertising leads may appear lower than it actually is.
- The Paid Search lead trend may appear to decline.
- Leads attributed to Display or Cross-network may appear to increase suddenly.
- Sales reports based on old filters may display incomplete data.
- Automated lead routing rules may segment leads incorrectly if they depend on source or medium values.
For this reason, Microsoft Advertising source definitions should be reviewed across CRM, marketing automation, and sales reporting systems.
UTM Persistence and Redirect Checks Are Becoming More Critical
This update makes the correct preservation of UTM parameters even more important. Because multiple source and medium values will be used under the new structure, any parameter loss on the landing page may cause channel classification to break more quickly.
The following checks should be performed:
- Do landing page URLs remove UTM parameters?
- Are parameters preserved during HTTP to HTTPS redirects?
- Are query strings preserved during www and non-www redirects?
- Is UTM information preserved during route changes in SPA structures?
- Are hidden field values populated correctly during form submission?
- If UTM values are stored in cookies or localStorage, are the new source and medium values supported?
- Does the server-side GTM or backend attribution structure process the new values correctly?
If these checks are not completed, the measurement improvements introduced by Microsoft Advertising may not be captured correctly by the website or CRM infrastructure.
Risk of Misinterpretation in Historical Comparisons
September 2, 2026, should be treated as a reporting break date. Because the channel distribution of Microsoft Advertising traffic may change before and after this date, year-over-year and period-over-period comparisons should be interpreted carefully.
For example, if Paid Search traffic appears to decline after September 2026, the reason may not be lower campaign performance. Shopping, Audience, or Performance Max traffic may simply have been reclassified into different channels. For this reason, it is recommended that an annotation be added for September 2, 2026, in GA4, Looker Studio, BigQuery, and other reporting tools. This date should also be highlighted in performance presentations.
What Should Advertisers Do?
Microsoft Advertising states that the change will be applied automatically to accounts using UTM auto-tagging. Therefore, no manual migration process is expected at a basic level. However, this does not mean advertisers should avoid performing any checks.
The following actions are recommended:
1. Check the Auto-Tagging Status in Microsoft Advertising
Confirm whether UTM auto-tagging is enabled in the account. If auto-tagging is not being used, this update may not directly affect the account.
2. Review Existing Tracking Templates and Final URL Suffixes
Manual UTM structures, tracking templates, and final URL suffix fields should be reviewed. If different tracking templates are used at the account, campaign, ad group, or ad level, the potential risk of conflict with the new automatic UTM structure should be evaluated.
3. Review GA4 Channel Reports Separately Before and After September 2
Channel performance before and after September 2 should not be evaluated as part of a single uninterrupted trend. Changes in Paid Search, Display, Paid Shopping, Paid Video, and Cross-network should be analysed separately.
4. Update Looker Studio Dashboards
If Microsoft Advertising filters are based only on bing / cpc, they may display incomplete data. More comprehensive filter structures should be prepared.
5. Test CRM and Form Hidden Field Structures
Confirm that the new UTM values are written correctly into form fields. New values such as msads, bingvideo, and cross-network should be grouped correctly within lead source reports.
6. Revise BigQuery Queries
Microsoft Advertising definitions should be updated within queries that use the GA4 export. Classifications based on source, medium, campaign, and default channel group should be reviewed.
7. Test Using Live Click URLs
After the update goes live, test clicks should be performed from different campaign formats to verify the actual UTM values generated in landing page URLs. This is important for confirming how the values described in published sources are applied at the account level.
Will MSCLKID and UET Be Affected by This Change?
This update relates specifically to UTM auto-tagging. Microsoft Click ID, or MSCLKID, and Universal Event Tracking, or UET, serve separate purposes within Microsoft Advertising’s own conversion measurement system.
MSCLKID is used to associate an advertising click with conversion measurement inside Microsoft Advertising. UTM parameters, on the other hand, are primarily used to identify traffic sources, campaign information, and channel classification within third-party analytics platforms.
Therefore, while the UTM auto-tagging update may affect reporting classifications in GA4 and similar analytics platforms, the UET implementation should still be checked separately to ensure it is functioning correctly. It is particularly important to preserve both UTM parameters and the MSCLKID value throughout redirect processes.
How May Budget Optimisation Be Affected?
This change may support healthier budget optimisation decisions. When different campaign formats are grouped under the same paid search channel, genuine performance differences may be hidden.
Under the new structure, advertisers may be able to answer the following questions more accurately:
- Do Search campaigns genuinely have the highest conversion rate?
- Audience Ads may generate impression-based traffic, but what is their contribution to conversions?
- How do Shopping campaigns perform in terms of product-level revenue?
- Do Video campaigns contribute to upper-funnel performance?
- How do Performance Max campaigns affect total contribution within the Cross-network structure?
This separation is particularly important for brands managing Microsoft Advertising accounts that use multiple campaign formats. Instead of evaluating performance under a single channel, advertisers will be able to perform more meaningful optimisation based on campaign type.
