Guide · Fontana, CA
How Many Porta Potties Do I Need? Event and Jobsite Calculator
Enter your guests and hours, or your crew size, and get a unit count in whole numbers. The assumptions are spelled out below so you can check every step.
By Fontana, owner · Reviewed
How many porta potties do you need per guest?
You need 1 standard porta potty for every 50 guests at an event of up to 4 hours. Add 1 unit per 250 guests for events of 5 to 8 hours, and 2 per 250 guests beyond 8 hours. Add 1 unit per 200 guests when alcohol is served, because guests use the restroom more often.
| Guests | Up to 4 hrs | 5–8 hrs | 5–8 hrs + alcohol | 9+ hrs + alcohol |
|---|---|---|---|---|
| 50 | 1 | 2 | 3 | 4 |
| 75 | 2 | 3 | 4 | 5 |
| 100 | 2 | 3 | 4 | 5 |
| 150 | 3 | 4 | 5 | 6 |
| 200 | 4 | 5 | 6 | 7 |
| 250 | 5 | 6 | 8 | 9 |
| 300 | 6 | 8 | 10 | 12 |
| 500 | 10 | 12 | 15 | 17 |
| 1,000 | 20 | 24 | 29 | 33 |
This is our own sizing method, built from what keeps lines short at real events. It is a planning tool, not a legal requirement. Your venue, city permit or county health permit can require more.
How many porta potties for a wedding of 150 guests?
A 150-guest wedding of 5 hours with a bar needs 5 standard porta potties. Start with 3 units for 150 guests, add 1 because the wedding runs 5 hours, and add 1 because alcohol is served. One 2-stall restroom trailer plus 1 deluxe flushing unit covers the same crowd.
Want us to check your count?
Call(601) 236-1718How many porta potties does a construction site need?
A California construction site needs 1 toilet per 20 workers of each sex, under Cal/OSHA §1526, plus 1 washing station per 20 workers under §1527. A crew of 18 men and 4 women needs 2 toilets and 2 washing stations. A crew under 5 can share 1 toilet.
See the full breakdown in our Cal/OSHA toilet requirements guide.
How many ADA units and handwashing stations do you need?
Public events need at least 5% of the portable toilets in each cluster to be accessible, with a minimum of 1, under 2010 ADA Standards §213.2. For food events, our recommendation is 1 two-sided handwashing station for every 3 standard units. Jobsites need 1 washing station per 20 workers.
Questions renters ask
Do more women at an event mean more units?
Yes. Women's restroom visits take longer, so events with mostly women guests, such as bridal showers, should add about 1 unit per 100 guests to the totals above.
Do kids count as guests?
Yes. Count everyone on site, including children, staff, vendors and performers.
Does a restroom trailer replace several porta potties?
A 2-stall restroom trailer serves about 75–100 guests at a 4-to-5-hour event, roughly the work of 2–3 standard units.
What if my event lasts several days?
Size for the busiest day, then schedule a service visit each night so tanks are empty and paper is restocked.