Microsoft Advertising is making another change to how advertisers use automated bidding, this time removing Max CPC from the setup of new campaigns.
Microsoft says the setting can interfere with its bidding system’s ability to optimize toward performance goals, even when advertisers set the maximum CPC above their average CPC.
The change takes effect Oct. 1, with some important exceptions for existing campaigns and portfolio bid strategies.
What’s Changing With Max CPC
Beginning Oct. 1, 2026, Max CPC will no longer be available when creating new non-portfolio campaigns using Target CPA, Target ROAS, Maximize Conversions, Maximize Conversion Value or Maximize Clicks.
The change only applies to new campaigns. Existing campaigns created before Oct. 1 that already use Max CPC can keep the setting.
Max CPC will also remain available for new and existing campaigns using portfolio bid strategies. Target Impression Share and Enhanced CPC are not affected.
Microsoft will initially remove Max CPC from campaign creation in the user interface. The setting will also be removed from Microsoft Advertising Editor, although timing has not been announced. An API update is expected later.
Microsoft says Max CPC can interfere with its automated bidding systems, including when the maximum is set above a campaign’s average CPC.
In those cases, the setting can give the bidding system conflicting instructions. An advertiser may ask Microsoft to optimize toward a specific CPA or ROAS while simultaneously limiting how much it can bid in auctions that could help achieve that goal.
Microsoft said it has also been making back-end improvements to automated bidding to improve responsiveness and help advertisers reach their targets.
What This Means For Advertisers
The immediate impact should be fairly limited for advertisers already relying on automated bidding without Max CPC.
For those that regularly use Max CPC alongside these strategies, new campaigns will require a different approach beginning Oct. 1.
Microsoft recommends managing performance through controls tied more directly to campaign outcomes. That includes budgets, Target CPA and Target ROAS goals, conversion value rules and seasonality adjustments when appropriate.
That may require a mindset change for advertisers that use Max CPC as a safeguard against individual bids getting too high.
Without that option, the quality of the inputs guiding automated bidding becomes more important. Conversion tracking should accurately reflect the actions that matter to the business, while CPA and ROAS targets need to reflect what advertisers are realistically willing to pay for those outcomes.
Conversion value rules can provide another layer of control. Advertisers can use them to tell Microsoft that certain audiences, locations or device types are worth more to the business, giving automated bidding additional information to use when determining how much to bid.
There is also no requirement to remove Max CPC from existing campaigns. Advertisers with a specific reason for maintaining that control can keep it on those campaigns or use a portfolio bid strategy for new ones.
For now, that makes this less of an immediate migration and more of a change advertisers need to account for when building campaigns after Oct. 1.
Looking Ahead
Microsoft is giving advertisers some flexibility with the Oct. 1 change. Existing campaigns won’t lose Max CPC, and portfolio strategies will continue supporting it.
That means there’s no reason to start removing Max CPC from campaigns simply because of this update.
Instead, advertisers should review where they currently use the setting and why. If Max CPC is an important control for certain campaigns, portfolio bidding will remain an option for new campaigns after Oct. 1.
For everyone else, the change puts more emphasis on the other controls Microsoft recommends, including budgets, performance targets and conversion value rules.
The next several weeks are a good time to review current campaign setups and determine whether any internal processes or campaign templates need to change before the new requirements take effect.
