Microsoft Ads performance drop: how to find which change caused it

Why did my Microsoft Ads performance drop?

Most Microsoft Ads drops start with a change, not with the market. The change can come from your team, from an automated tool, from the website or from Google Ads itself, because many accounts copy their campaigns from Google with the import tool.

That last point is what makes Microsoft Ads different. An edit you make in Google Ads on Thursday can land in Microsoft Advertising on Sunday, when the scheduled import runs, and nobody on the team thinks of it as a Microsoft change. When results fall a few days later, the cause sits in another platform.

The usual suspects, in the order worth checking:

• Tracking: the UET tag stopped firing, a conversion goal changed, or consent signals stopped reaching Microsoft.
• Imports: a scheduled Google import updated bids, bid strategies, budgets, statuses or URLs.
• Direct edits: bid strategy, budget, targeting or ad changes made in the web interface, Editor, scripts or automated rules.
• Outside changes: a new landing page, a form change, a price or stock change, or a seasonal shift.

The rest of this article walks through each one and shows how to prove which change moved the numbers. If you want the general method behind it, the guide to explaining a conversion drop to a client covers it step by step.

How do I tell a tracking problem from a real drop?

Check whether people stopped converting or whether Microsoft stopped seeing the conversions. If clicks and site sessions from Microsoft Ads are steady but conversions fell, suspect tracking before you touch a bid.

Three checks cover most cases:

1. Compare with your own data. Look at leads or orders from Microsoft traffic in your CRM, shop or analytics tool. If they held while Microsoft Ads conversions fell, the problem is measurement.
2. Check the UET tag and the goals. Confirm the tag still loads on the thank-you page and that nobody edited or replaced the conversion goal. A site redesign or a new tag manager version can remove the tag without anyone noticing.
3. Check consent signals. Microsoft Advertising has enforced explicit consent signals for site visits from the EEA, the UK and Switzerland since May 5, 2025, sent through the ad_storage parameter of UET Consent Mode, a TCF 2.0 string or Google Tag Manager. Microsoft says missing signals affect performance for those visits. A change to your cookie banner can trigger the same effect today.

Also note that conversion goals can be imported. The GoogleImportOption reference lists UpdateConversionGoals as an option that, when on, imports updates to existing conversion goals. If someone changed a goal in Google Ads, the Microsoft copy may have changed too. Our article on proving a consent banner caused a conversion drop goes deeper on the consent side.

Which Microsoft Ads changes most often cause a drop?

The changes that move results most are the ones that alter how much you bid, where you show and where the click lands. In accounts that use Google import, many of them arrive through the import rather than from a person.

Microsoft documents the import options in its GoogleImportOption reference. Most update options are on by default, which means later imports bring Google Ads edits across to items you imported before:

Imports can also delete items. The Google Ads import guide explains that with DeleteRemovedEntities set to true, the service deletes items that were removed from the Google Ads account. Schedules can be daily, weekly, monthly, once or "Auto", where Microsoft picks the timing.

How do I read Microsoft Advertising change history?

Use the change history page in Microsoft Advertising to see what was edited, when and by which tool. A Microsoft support answer on Microsoft Q&A says it lets you review every action taken on your campaigns over the past six months, and that eligible changes from the last 30 days can be undone from the Undo column.

The change history report in the API shows the fields that matter for a diagnosis. According to the report column reference:

• Tool tells you how the change was made, with values such as "API", "Automated rules", "Bulk upload", "Imports", "Editor", "Scripts" and "Web client (manual)".
• ChangedBy shows the username, or "Administrator" when the system made the change.
• OldValue and NewValue show the before and after for updates.
• DateTime is in the time zone of the campaign.

Filter by Tool = Imports first. If a drop starts right after an import, compare the before and after values with the edit made in Google Ads that week. The Google Ads change history guide shows how to read the Google side.

Two limits to keep in mind. The report request reference says change history can take about one hour to appear, so very recent edits may be missing. And change history only covers edits inside Microsoft Advertising: the website release, the cookie banner update or the CRM change does not appear there.

How do I isolate which change caused the Microsoft Ads drop?

Put every change from the 7 to 14 days before the drop on one timeline, then test them one at a time, starting with the most recent and the largest. The cause is usually the change that sits right before the first bad day.

1. Rule out tracking
2. Read change history
3. Line up every change
4. Test one hypothesis

Collect changes from all sources: Microsoft Ads change history, Google Ads change history for anything that was imported, tag manager versions, site releases, consent banner updates and promotions. Mark the day the metric moved. With every change on one timeline, you would see that a Google Ads bid edit was copied into Microsoft Ads by the import two days before the drop, instead of finding it a week later. A shared marketing change log in Changeline keeps that timeline per client; Google Ads edits can be imported automatically, and Microsoft Ads, site and tracking changes are logged by the team.

Then test one hypothesis at a time. Revert or adjust a single change, wait long enough for the data to settle and compare the same days of the week. If you change three things at once, you will not know which one fixed it.

Example: A client asks why Microsoft Ads leads fell 30% this week while Google Ads held steady. The team lines up the changes. On Thursday the target CPA in Google Ads went from 45 to 35. On Sunday the weekly import copied the new bid strategy to Microsoft Ads, with Tool = Imports in change history. Impressions fell from Monday. The team sets a separate target in Microsoft Ads and leads recover the following week. (Illustrative names and numbers.)

What should I do once I know what caused the drop?

Fix the cause, write down what you changed and why, and decide which import options should stay on. The goal is that the next drop takes minutes to explain, not days.

If the import was the cause, review your schedule and options. You can switch off update options for items you want to manage separately in Microsoft Ads, such as budgets or bid strategies, so a Google edit no longer overwrites them. Keep in mind that Microsoft says the option list is not a full list of what gets imported.

If the cause was tracking, fix the tag or the consent setup, then note the dates when data was missing so nobody reads that week as a real drop later. If the cause was a direct edit, keep it, adjust it or revert it, and record the result. Our article on finding the change behind a CPA spike covers how to judge a bid change once data comes back.

The marketing change log guide shows what to record for each change so the next diagnosis starts from a complete list.