Attrition clause

How attrition is calculated

The contract sets a percentage of the block you must fill, commonly 80 percent. If actual pickup falls below it, you pay a penalty on the shortfall, usually calculated against lost room revenue rather than the full rate. The exact basis varies by contract and is worth reading rather than assuming.

Why it exists

The hotel is holding inventory it cannot sell to anyone else. Attrition is how it prices that risk. Understanding it that way makes the negotiation clearer: you are not arguing about fairness, you are deciding who carries the forecasting risk.

What to negotiate

Three things move more often than organizers expect. The percentage itself. A review date partway through that lets you reduce the block without penalty. And a clause crediting rooms booked outside the block at the same hotel, which protects you when attendees book direct and still sleep there.

How to avoid triggering it

Block conservatively and add rooms later, which most hotels will accommodate when they have inventory. Track pickup weekly rather than checking at the cutoff. And put the booking link inside the registration flow so attendees see it at the moment they are already committing. See room block management software.