· 5 min read · Protecxo Media Team
Frequency, reach and the cost of showing the same ad too often
Reach and frequency pull against each other inside any budget. How to set frequency caps that protect efficiency without starving a campaign.
Inside a fixed budget, every additional impression shown to someone who has already seen your ad is an impression not shown to someone new. Frequency is therefore not just a user-experience question; it is a budget allocation decision.
Why frequency creeps up
Optimisation algorithms tend to favour people who have already engaged, because they are more likely to engage again. Retargeting pools are small and easy to saturate. And when several line items, channels or buying methods run in parallel, each with its own cap, the same person can be reached through all of them.
Setting caps that make sense
- Set caps at the campaign level where the buying platform allows it, not only per line item.
- Use different caps for different jobs: broader prospecting usually warrants a lower cap than a short retargeting window.
- Consider the time window as well as the number. Three impressions in a day and three in a month are very different experiences.
- Watch reach as well as frequency. If reach plateaus while spend continues, the campaign may be paying to repeat itself.
What to look at in reporting
Average frequency hides the extremes. Where available, a frequency distribution — how many people saw the ad once, twice, five times or more — shows whether the campaign is reaching broadly or concentrating on a small group.
There is no universal ideal frequency. The right level depends on the message, the creative and the purchase cycle. What matters is that it is set deliberately, monitored, and adjusted when the data shows diminishing returns.