Planning for a marketing campaign: the spike you’re told about late

Forecasting · ~6 minute read

The demand your seasonal model can’t see

Most demand is reassuringly regular — the same weekly shape, the same annual rhythm, year after year. Marketing-driven demand isn’t. A campaign, a promotion, a price change, a product launch creates a spike that owes nothing to your seasonal model and everything to a decision someone else made, often without telling planning until the contacts are already arriving. Campaign demand is the classic avoidable surprise: predictable in principle, because somebody planned it, yet routinely unforecast in practice because the information never crossed the floor.

Sizing a spike you didn’t design

Campaign demand is driver-based, so you forecast it from the drivers, not from history. Reach (how many customers see it) times response rate (how many act) times contact rate (how many of those then call or chat) gives a first estimate — rough, but enormously better than being blindsided. The shape matters as much as the size: campaigns tend to spike hard at launch and tail off, with a secondary bump when a deadline looms, so a flat uplift over a fortnight will be wrong in both directions. And the uncertainty is real — response rates are hard to predict — so you plan a range and a flex response, not a single number you’ll defend to the death. The goal isn’t a perfect campaign forecast; it’s to be approximately ready instead of precisely surprised.

Baseline plus the campaign spike baseline (BAU) campaign launch spike + tail told (ideal) launch The gap between “told” and “launch” is the lead time you have to act.
Campaign demand spikes at launch and tails off. The earlier planning hears about it, the more of the response is a plan rather than a scramble.

The fix is a relationship, not a model

The real cure for campaign surprises isn’t a cleverer forecast; it’s a seat at the marketing table. Get planning onto the campaign calendar so launches arrive as inputs, not incidents. Build a simple, shared campaign demand model that marketing helps populate, so the contact rate becomes a number you agree rather than a shock you absorb. Plan the response in shape — flex up hard at launch, hold ring-fenced capacity or overtime for the spike, and protect business-as-usual service so the promotion doesn’t wreck the everyday experience. And close the loop afterwards: log what actually happened so the next campaign of that type forecasts itself. A planner who is in the room when the campaign is designed turns the most avoidable surprise in the building into just another line on the plan.

Pair this with decomposing demand by call reason, forecasting in ranges, and the staffing sensitivity calculator.