How we actually set a display advertising budget: impressions vs engaged clicks

Budgeting a display campaign purely on cost per impression rewards whatever inventory is cheapest to buy, which is rarely the inventory that reaches the right audience. A campaign optimized to maximize impressions per dollar naturally drifts toward low-cost, low-relevance placements, because that is where impressions are cheapest, and a budget managed this way can hit every efficiency target on a report while reaching almost nobody worth reaching.

We set budgets around cost per engaged click instead, meaning a click from an account that matches the target profile, not raw click volume either. This changes where the money actually goes: a more expensive placement against a precisely matched audience can be the better buy even at a higher cost per impression, if the resulting clicks come from accounts genuinely worth reaching, because cheap impressions against the wrong audience are not actually cheap once measured against what they produce.

This means budget allocation shifts mid-flight based on which placements are producing engaged clicks, not which ones are producing the most impressions for the least money. A placement delivering impressions efficiently but engagement poorly gets less budget even if its raw cost-per-impression number looks strong, because efficient delivery to the wrong audience is not the metric that matters.

We also budget separately for the two jobs display does, brand awareness and retargeting, rather than one blended number. Awareness budget tolerates a higher cost per engaged click because it is buying longer-term recognition with a broader relevant audience. Retargeting budget gets judged more strictly, since it is working an audience that has already shown interest and should convert at a meaningfully higher rate for the spend.

Setting the budget around what the campaign is actually trying to produce, rather than around the cheapest available inventory, is what keeps display spend accountable to real engagement instead of a vanity efficiency number, and it is the same live-optimization discipline that governs every other part of a display campaign we run, treated as an ongoing decision rather than a number fixed once at the start.