Key facts
- Parties: 1 unit per 50 guests for 4 hours.
- Up to 6 hours: 1 per 40; up to 8 hours: 1 per 30.
- Alcohol: add 25%.
- Accessible: 5% per cluster, minimum one.
- Crews: 1 toilet per 20, then 1 seat + 1 urinal per 40.
How many porta potties do I need?
Plan 1 standard unit per 50 guests for a 4-hour event, 1 per 40 up to 6 hours, 1 per 30 up to 8 hours and 1 per 25 beyond that. Add 25% when alcohol is served, make 5% of each cluster accessible (minimum one), and add one hand-washing station per 4 units where food is served.
Event calculator
| Guests | 4 hours | 6 hours | 8 hours |
|---|---|---|---|
| 25 | 1 | 1 | 1 |
| 50 | 1 | 2 | 2 |
| 100 | 2 | 3 | 4 |
| 150 | 3 | 4 | 5 |
| 250 | 5 | 7 | 9 |
| 500 | 10 | 13 | 17 |
How many for a construction crew?
Under OSHA 29 CFR 1926.51 Table D-1, 20 or fewer workers need 1 toilet; more than 20 need 1 toilet seat and 1 urinal per 40 workers; 200 or more need 1 seat and 1 urinal per 50. Count your busiest day, when framers, roofers and electricians overlap.
| Crew | OSHA minimum |
|---|---|
| 1–20 | 1 toilet |
| 21–40 | 1 seat + 1 urinal |
| 41–80 | 2 seats + 2 urinals |
| 81–120 | 3 seats + 3 urinals |
| 200+ | 1 seat + 1 urinal per 50 |
How many for a race?
Plan about 1 unit per 75–100 runners at the start/finish and 1–2 at each aid station, with an accessible unit in every cluster. A half-marathon organizer in our log planned 14 units for a loop course — 12 standard and 2 accessible — with most at the shared start/finish and a standard plus an accessible unit at the halfway aid station.
Dispatch notebook
The organizer's own count: “12 normal porta-potties, and then two ADA-accessible ones… 10 normal and one ADA placed at the beginning… and then at the halfway point… another toilet and then another ADA one.”
Source: 50-call sample, 2026 phone log. Names, numbers, addresses and payment details removed.
When should I add a mid-event cleaning?
Add one when an event runs past 8 hours, spans two days, or puts more than about 100 uses on each unit. Festivals and two-day fairs need a pump-and-restock overnight. A single-afternoon party almost never does. The extra visit is quoted before booking, never added afterward.
Asked on our phone line
Questions callers asked us
How many porta potties do I need for my party?
Plan 1 standard unit per 50 guests for a 4-hour event, 1 per 40 up to 6 hours, and 1 per 30 up to 8 hours, then add one more if alcohol is served. A 40-person party needs one unit. A 100-guest, four-hour event needs two — the same answer a caller got for her 100-guest gathering.
How many porta potties for a 5K or half marathon?
Plan about 1 unit per 75–100 runners at the start/finish and 1–2 units at each aid station, with at least one accessible unit per cluster. A first-time half-marathon organizer in our log planned 14 units — 12 standard and 2 accessible — with most at the start/finish and a standard plus an accessible unit at the halfway aid station.
How many units for a church vendor fair?
For 50 vendors and a few hundred shoppers over 4–6 hours, plan 2–3 standard units and one hand-washing station near any food. A church in our log planned “maybe one, possibly two” units and a hand-washing station for its first vendor event. Book the Friday before, since we deliver ahead of Saturday events.
How many porta potties does my crew need?
OSHA 29 CFR 1926.51 Table D-1 requires 1 toilet for 20 or fewer workers, then 1 toilet seat and 1 urinal per 40 workers. Our units include a urinal. A 68-unit apartment build that starts with a few framers can begin with two units and add more as trades arrive.
Do I need a wheelchair-accessible porta potty?
If your event is open to the public, plan at least 5% of units in each cluster as accessible, minimum one, under the 2010 ADA Standards §213.2. For private parties, add one whenever a guest uses a wheelchair or walker. A race organizer in our log planned 12 standard and 2 accessible units — one accessible unit at each restroom cluster.
Is a sink inside the unit better than a separate hand-washing station?
For one or two units, a sink inside is cheaper and saves space. For three or more units, a separate two-sided station by the food line serves more people. A caller pricing two toilets noticed the catch: with one sink unit and one plain unit, half the guests must walk to the other door to wash their hands.