Digital Campaigns

Q4 Ad Planning: What to Lock In Before CPMs Spike

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Every year the same conversation happens in November. Costs per thousand impressions have doubled, the campaign that was profitable in September is not any more, and someone asks whether we should pause. By then the useful decisions are all behind you. The quarter is won or lost in August and September, when impressions are still cheap and nobody is thinking about Christmas.

The pattern is predictable enough to plan around. Fourth-quarter costs typically run twenty to fifty percent above the rest of the year, the ramp starts in late October, and the peak days — Black Friday, Cyber Monday, the fortnight before Christmas — can run far higher again, sometimes double or triple a normal week. Then, on the 26th of December, the whole thing collapses.

What Actually Happens to the Auction

Nothing mysterious: more advertisers bid for a supply of attention that does not grow. Large retailers with annual budgets arrive at the same time as every small business that decided to "do something for Christmas", and the platforms allocate impressions to whoever pays most.

Two consequences follow, and the second catches people out. Your costs rise even if you change nothing — and your creative wears out faster, because the same audience is seeing far more advertising in total. A creative rotation that lasted six weeks in September will be exhausted in one or two.

The Decisions to Make Now

Build your audiences while impressions are cheap. Retargeting pools, video viewers, email and SMS subscribers, and customer lists uploaded for matching — all of these cost less to build in August than in November. An advertiser going into December with a large warm audience is buying at a completely different effective price to one starting cold.

Shoot the creative now. You cannot brief a shoot in the second week of November. Produce more variations than feel necessary, in the formats each platform actually serves, and include at least two different angles on the offer rather than one idea in five crops.

Test offers in September. Whatever you plan to push at peak — the bundle, the free delivery threshold, the gift guide — test it while a click is cheap. Scaling a proven offer into an expensive auction works. Discovering your offer is weak in an expensive auction is how budgets disappear.

Decide your ceiling in advance. Agree now what you are willing to pay for an acquisition in December, and set cost caps or target returns accordingly. That number should be a business decision made calmly in August, not a panicked judgement at 11pm on Black Friday.

The August checklist
  • Grow and refresh first-party lists; upload and match them before the season starts.
  • Book creative production for September delivery, with peak-period variations included.
  • Test the peak offer at low cost and keep the winner.
  • Load-test the site and checkout — and check express payment options are live.
  • Agree the maximum acceptable cost per acquisition and write it down.
  • Reserve budget for the last week of December, when costs fall off a cliff.

Running the Quarter

Front-load within each event. Competition on the first day of a sale window is usually softer than on the last, so weighting spend toward the earlier half generally buys more at a better rate than saving it for a finale.

Refresh creative far more often than feels natural — every five to seven days during peak weeks rather than monthly. Frequency climbs fast when everyone is advertising, and fatigue shows up as rising costs that look like an auction problem but are really a creative problem.

Q4 does not reward the biggest budget. It rewards the advertiser who did the cheap work in August.

And plan for the window nobody books: the days between Christmas and mid-January. Costs drop sharply, intent is still high, and gift-card balances are being spent. For many businesses it is the best value fortnight of the entire year, and most of their competitors have already switched off.

Conclusion

You cannot control the auction, but you can arrive prepared. Build audiences and produce creative while attention is cheap, prove the offer in September, set your cost ceiling before emotion is involved, and keep budget back for the collapse in late December. The businesses that do this spend the fourth quarter scaling something that works. Everyone else spends it discovering what does not.

Planning your Q4 spend?

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