Wash Factor

Definition

Wash factor is the expected percentage of confirmed reservations that won’t materialize — through cancellation, no-show, or modification. A wash factor of 8% on a 100-room block means you should plan for ~92 rooms actually occupied.

What it tells you

Wash matters most on groups, where a single block can be 30+ rooms. Underestimating wash on a group leaves rooms empty; overestimating leads to overbooking pressure.

How to track it

Computed from historical cancellation + no-show data, ideally segmented by booking type, lead time, and rate plan. The longer the lead time, the higher the wash typically.

Where it fits

A standard input to group decisions, overbooking levels, and short-term forecasting. The discipline is to have wash factors by segment rather than one blanket number.