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Room blocks and attrition: the organizer's guide

Everything an organizer needs to hold about room blocks in one place: how the contract works, what the clause costs when pickup misses, how large a block to sign for, and what to do about the majority of your audience who never touch it.

Room block attrition calculatorEnter your block, your clause and your pickup. See exactly what an unfilled room costs you.Free, no sign-up →Room block size calculatorWork out how many rooms to contract for — and how many nights your attendees will book somewhere else.Free, no sign-up →

The contract in one paragraph

A hotel agrees to hold rooms for your attendees at a set rate. You agree that a certain share of those rooms will be booked and paid for. Two dates govern the deal: the cutoff, when unbooked rooms return to the hotel’s general inventory, and whatever deadline your attrition clause names for measuring pickup. Almost everything that goes wrong with room blocks traces back to the fact that both the block size and the clause are agreed long before anyone knows how many people are coming.

What attrition actually costs

The usual calculation is unfilled rooms below the threshold, times the contracted rate, times the nights held. On a hundred-room block at an 80% clause with 62 rooms picked up, eighteen rooms are billable for every night the block covered, which at a typical rate is a five-figure invoice for rooms nobody slept in. The attrition calculator does that arithmetic on your own contract, and shows how many rooms you are from clear.

Three details in the clause change the number more than the threshold does. Damages based on lost profit rather than the full room rate are dramatically cheaper. Pickup measured across the whole block, rather than night by night, forgives a soft shoulder night. And a resell credit means rooms the hotel sold anyway are deducted from what you owe. All three are negotiable, and all three are more often absent than refused.

Sizing the block

Work from travellers, not attendance. Expected attendance times the share who come from far enough to need a bed, divided by realistic people per room, gives you the rooms your event genuinely creates. Only a portion of those will use your block at all. Contract slightly under that portion: the block size calculator lands 10% below expected pickup on purpose, because adding rooms to a block that is filling fast is a phone call, and unfilled rooms are an invoice.

The part nobody measures

Whatever your block captures, the rest of your travelling audience still books a bed within a few miles of your gate. That spend is real, it is caused entirely by your event, and none of it appears in your pickup report, your attrition maths, or your accounts. In a real event market we measured, roughly 70% of the lodging money was committed inside the final 30 days and about 31% of it went to properties inside a sold-out block, which tells you both that the demand is large and that it arrives too late for a contract signed a year earlier to do anything about it.

That overflow is the thing Bookend exists for. Rather than holding more inventory and signing for more risk, you put real places to stay in front of the attendee at the moment they are deciding, on your own confirmation page, and take a share of what they book. Bookings carry a 15 to 20% commission and we only earn when you do. See what your share would be.

Common questions

What is a hotel room block?

A room block is an agreement in which a hotel holds a set number of rooms for your attendees at an agreed rate until a cutoff date. In return you normally guarantee that a share of them will be booked and paid for. The rate is the benefit; the guarantee is the cost.

What is attrition in a hotel contract?

Attrition is the gap between the rooms you promised to fill and the rooms your attendees actually booked. If a clause sets the threshold at 80% of a 100-room block, the 80th room is the line: fill fewer and the hotel bills you for the difference at the contracted rate for every night held.

What happens after the cutoff date?

Unbooked rooms go back to the hotel to sell at whatever rate it likes, and your attendees lose the negotiated rate. Passing the cutoff does not by itself cancel your attrition obligation, which is the detail that surprises people most often.

Do most attendees book inside the block?

Usually not. The block competes with booking sites, loyalty programmes and rentals, and it typically wins only a minority of the travelling audience. That is not a planning failure, but it does mean the block is a poor measure of how much lodging your event actually generates.