Sizing guide · calculator
How Many Porta Potties Do I Need?
Enter your headcount and hours. The calculator applies our planning method for events and the Cal/OSHA counts for crews, and shows the math.
Tap to call dispatch · a real person answers(707) 781-5587- Same-day by 1 pm call
- Weekly service included
- Every charge itemized
- Events1 unit per 50 guests, up to 4 hours.
- Long events+1 unit per 150 guests past 4 hours.
- Alcohol+1 unit when a bar is open.
- Crews1 toilet per 20 workers (Cal/OSHA).
- Accessible5% of each cluster, at least 1.
Porta potty calculator
The porta potty calculator below gives total toilets, wheelchair-accessible units and handwashing stations. For events it uses 1 unit per 50 guests, plus 1 per 150 guests past 4 hours, plus 1 for alcohol. For crews it uses Cal/OSHA's 1 per 20 workers and our 1-per-10 comfort target.
Example loaded: 150 guests, 5 hours, bar.
How many porta potties for 100, 150 or 200 guests?
A 100-guest event under 4 hours needs 2 porta potties. A 150-guest, 5-hour wedding with a bar needs 5: 3 for the headcount, 1 for the extra hour and 1 for alcohol. A 200-guest, 6-hour party with alcohol needs 7. Each total includes 1 wheelchair-accessible unit.
| Guests | Up to 4 hours | 4–8 hours | 4–8 hours + alcohol |
|---|---|---|---|
| 25 | 1 | 2 | 3 |
| 50 | 1 | 2 | 3 |
| 100 | 2 | 3 | 4 |
| 150 | 3 | 4 | 5 |
| 200 | 4 | 6 | 7 |
| 300 | 6 | 8 | 9 |
| 500 | 10 | 14 | 15 |
| 1,000 | 20 | 27 | 28 |
Our planning method. Add a second set of units, or a mid-event service, for events over 8 hours or multi-day festivals.
Worked example: a 150-guest wedding with a bar
A 150-guest wedding running 5 hours with an open bar needs 5 units. Step 1: 150 ÷ 50 = 3 units. Step 2: the event runs past 4 hours, so add 1 unit per 150 guests, which is 1. Step 3: alcohol is served, so add 1. Total 5, with 1 accessible.
- Base: 150 guests ÷ 50 = 3 units.
- Past 4 hours: 150 ÷ 150 = +1 unit.
- Alcohol: +1 unit.
- Accessible: 5% of 5 = 0.25, round up to 1 (counted inside the 5).
- Handwashing: 5 ÷ 4 rounded up = 2 stations, or use flushing units with sinks.
Want a second opinion on your count?
Dispatch checks your layout and headcount on the call.
Live answer Mon–Sat 7 am–7 pm
How many toilets does a construction crew need?
A construction crew needs at least 1 toilet per 20 workers of each sex under Cal/OSHA 8 CCR 1526. Twenty workers need 1 toilet by law, but one unit per 10 workers on weekly service keeps lines short and odor low. Federal OSHA 29 CFR 1926.51 sets 1 toilet for 20 or fewer workers.
| Workers | Cal/OSHA minimum | Comfortable on weekly service |
|---|---|---|
| 10 | 1 | 1 |
| 20 | 1 | 2 |
| 30 | 2 | 3 |
| 50 | 3 | 5 |
| 100 | 5 | 10, or 5 serviced 2× weekly |
How many accessible units are required?
At least 5% of portable toilets in each cluster must be wheelchair accessible, and never fewer than 1, under 2010 ADA Standards §213.2. A cluster of 20 needs 1. A cluster of 21 to 40 needs 2. This is the legal minimum. Confirm with your venue or permit office.
Does alcohol really need an extra unit?
Guests drinking beer, wine or cocktails use restrooms more often. Adding 1 unit for an open bar keeps lines short in the last two hours.
Should I plan more units for a mostly female guest list?
Women use restrooms longer on average. For a mostly female crowd, add 1 unit per 100 guests or choose units without urinals.
Can the house bathroom count toward my total?
Do not count a house bathroom for a party over 25. Small sewer lines and septic tanks back up under heavy use.
How many units for a 3-day festival?
Use the 4–8 hour column for the busiest day, then book nightly service. Nightly pump-out resets each unit for the next day.
Get a written, itemized quote
Calling is the fastest way to lock in a delivery date, because dispatch can confirm the truck route while you are on the line. Prefer writing? Send six details and we reply with an itemized quote: unit, delivery, pickup, servicing and tax on separate lines.
Call now (707) 781-5587Live answer Mon–Sat 7 am–7 pm. Written quotes go out the same business day.