How many stalls does a restroom trailer need for 200 wedding guests?

A four-stall restroom trailer is the size I would start with for 200 wedding guests over six hours with a full bar and dinner.

There is no OSHA or ADA stall-count formula for wedding guests the way construction sites have toilet minimums under OSHA 1926.51. Event sizing comes down to peak demand. Alcohol and a sit-down dinner create two big rushes: right after the ceremony and again after dinner when people get up and move around. Two stalls get long lines at those peaks. Eight stalls is usually more than you need unless you also want separate banks with room to spare.

A four-stall unit with flushing toilets and sinks handles that crowd on most weddings I have helped plan, especially if the trailer sits close to the reception instead of a long walk across the field. Ask whether at least one stall is an accessible bay so guests who need it are covered the same way you would cover permanent restrooms. Confirm the unit has enough freshwater and waste capacity for a six-hour window so you are not calling for a mid-event service visit.

If your guest list skews heavily one gender, or the dance floor runs well past six hours, bump to six stalls rather than jumping straight to eight.