CPM (cost per mille) is the cost of a thousand ad impressions. You pay for your ad being shown, whether or not anyone clicks on it. It’s the basic buying rate in Meta Ads: the system sells your ad in an auction for attention, and CPM tells you what that attention costs right now.
What pushes CPM up?
Three things: competition for the audience, the quality of your creative and the season. In Poland, Meta Ads CPM can double in November and December, when every shop is bidding for the same people in the run-up to Christmas. Narrow audiences cost more too: the fewer people the system can show your ad to, the higher the price. And weak creative that people ignore or hide gets higher rates from the system, because it spoils the experience for users.
What should you do when CPM rises?
First, check whether the season or worn-out creative is to blame. A falling CTR alongside a rising CPM is a classic sign that people have seen the ad too many times. In practice, refreshing your creative and broadening the audience usually pays off better than trying to outbid the competition. Remember, too, that CPM is a buying cost and tells you nothing about results: a campaign with a higher CPM and better creative will usually outperform cheap impressions served to random people. Ultimately, what counts is the cost per click (CPC) and the cost of acquiring a customer.
