Bid adjustments under Smart Bidding

The fundamental shift: multipliers versus signals#

Under Manual CPC, a +50% device bid adjustment increases a £2.00 bid to £3.00. Under Smart Bidding (Target CPA and Target ROAS), manual adjustments no longer act as strict mathematical multipliers on auction bids.

Instead, as outlined in Microsoft Smart Bidding Behavior Docs, 2026, the algorithm incorporates device, location, and time signals into its real-time machine learning models.

Device bid adjustments under Target CPA#

In Target CPA campaigns, setting a device bid adjustment modifies your target CPA rather than the underlying bid. For example, a +20% mobile adjustment informs the algorithm that you are willing to accept a 20% higher cost per acquisition on mobile leads.

Setting a -100% adjustment remains the sole deterministic override, completely preventing ad impressions on that device category as confirmed in Microsoft Campaign Management Service, 2026.

LinkedIn profile adjustments under Smart Bidding#

LinkedIn Profile Targeting bid adjustments (Company, Industry, Job Function) serve as high-priority audience signals for automated bidding models, steering budget towards enterprise decision-makers.

Location and ad schedule interactions#

Smart Bidding natively evaluates geographic conversion probability and time-of-day trends at the auction level, rendering manual hourly bid adjustments largely redundant unless operational sales hours require strict gating.

Consult our Microsoft Ads Hub for detailed audience signal frameworks.

Bid adjustment behaviour comparison table#

The table below summarizes how each manual bid modifier functions across Manual and Smart Bidding strategies.

Frequently asked questions#