How Many Porta Potties Do I Need?
How many porta potties do I need? Start with 1 standard unit per 50 guests for an event up to 4 hours, then add units for long events, alcohol, and access. This guide gives you one clear method, a calculator, an event chart, and the OSHA crew table.
Same-day cutoff is 12:00 PM Mon–Sat (Central)
- Delivery areaThe same sizing method works for every town we serve, from Midland to Hobbs, NM.
- ArrivalSize your order before you call; same-day delivery needs the order in by 12:00 PM.
- Which unitSize with standard units, then swap 1 or more for accessible units.
- CleaningEvents over 3 days or 250+ guests should add a mid-event service visit.
- Full costOnce you know the count, the texted quote adds delivery, service and 8.25% tax.
How many porta potties do I need for my event?
Start with 1 standard porta potty per 50 guests for an event up to 4 hours. Add 1 unit per 100 guests if the event runs longer than 4 hours. Add 1 unit per 100 guests if alcohol is served. Make at least 1 unit wheelchair-accessible, and add hand-washing stations if food is served.
Enter your guest count, hours, and whether a bar is open. The calculator runs the same 5-step method Jack uses on the phone.
Method: Jack Rental Works sizing method; construction minimums from OSHA 29 CFR 1926.51 Table D-1; accessible-unit share from 2010 ADA Standards §213.2. Confirm with your permit office, venue or safety manager — this is not legal advice.
Have a crew instead of guests? Skip to the construction and oilfield section below.
What is the exact 5-step sizing method?
The Jack Rental Works method has 5 steps. Use 1 unit per 50 guests as the base. Add 1 per 100 guests past 4 hours. Add 1 per 100 guests for alcohol, minimum 1. Make at least 1 unit wheelchair-accessible. Add 1 hand-washing station per 4 toilets when food is served.
- Base count. Divide guests by 50 and round up. This covers an event up to 4 hours.
- Long event. If the event runs past 4 hours, add 1 unit for every 100 guests, rounded up.
- Alcohol. If drinks are served, add 1 unit for every 100 guests, rounded up. Always add at least 1.
- Access. Make at least 1 unit wheelchair-accessible. For big clusters, at least 5% of the units in each cluster should be accessible, rounded up.
- Hand washing. If food is served or no indoor sink is open, add 1 hand-washing station per 4 toilets. The minimum is 1.
Worked example: 150 guests, 6 hours, with a bar
Base is 150 ÷ 50 = 3 units. The event runs past 4 hours, so add 150 ÷ 100 = 1.5, rounded up to 2. A bar adds another 2. That is 7 units, with 1 of them wheelchair-accessible. Seven toilets ÷ 4 = 1.75, so add 2 hand-washing stations.
Worked example: 40 guests, 3 hours, no alcohol
Base is 40 ÷ 50 = 0.8, rounded up to 1 unit. No time or alcohol add-ons apply. Make that 1 unit wheelchair-accessible if any guest uses a wheelchair or walker, and add 1 hand-washing station if food is served.
Worked example: 600 guests, 8 hours, with beer sales
Base is 600 ÷ 50 = 12 units. Long event adds 6. Alcohol adds 6. That is 24 units. Five percent of 24 is 1.2, so at least 2 must be accessible. Add 6 hand-washing stations. A crowd this size also needs a mid-event service visit. Our festival porta potty page covers layout for big crowds.
Want Jack to check your count?
Call (432) 239-8885 with guests, hours, and food or drinks. You get a sized, texted quote.
How many units do you need for 25 to 1,000 guests?
For a 4-hour event with no alcohol, 100 guests need 2 units and 500 guests need 10 units. For an 8-hour event, 100 guests need 3 units and 500 guests need 15 units. Add the alcohol units on top. The chart below counts toilets, accessible units within that count, and hand-washing stations.
| Guests | Toilets, up to 4 h | Toilets, 8 h | Accessible (in count) | Handwash, 4 h / 8 h | Add for alcohol |
|---|---|---|---|---|---|
| 25 | 1 | 2 | 1 | 1 / 1 | +1 |
| 50 | 1 | 2 | 1 | 1 / 1 | +1 |
| 75 | 2 | 3 | 1 | 1 / 1 | +1 |
| 100 | 2 | 3 | 1 | 1 / 1 | +1 |
| 150 | 3 | 5 | 1 | 1 / 2 | +2 |
| 200 | 4 | 6 | 1 | 1 / 2 | +2 |
| 250 | 5 | 8 | 1 | 2 / 2 | +3 |
| 300 | 6 | 9 | 1 | 2 / 3 | +3 |
| 400 | 8 | 12 | 1 | 2 / 3 | +4 |
| 500 | 10 | 15 | 1 | 3 / 4 | +5 |
| 750 | 15 | 23 | 1 / 2 | 4 / 6 | +8 |
| 1,000 | 20 | 30 | 1 / 2 | 5 / 8 | +10 |
Accessible counts show 4-hour / 8-hour where they differ. Once you add alcohol units, recheck the 5% accessible rule and the handwash ratio against the new total.
Why does alcohol change the count?
Alcohol makes guests use the restroom more often, so lines grow fast after the first hour of a bar. Our method adds 1 unit for every 100 guests when drinks are served, with a minimum of 1 extra unit. A 60-guest party with beer gets 2 units base plus 1 for alcohol.
Heavy-drinking events, like a reception with an open bar, fill tanks faster than the manufacturer rating assumes. A 2-stall restroom trailer rated for about 150 guests over 6 hours serves fewer at a heavy-drinking event. Tell us if the bar runs the whole night.
Weddings are where this matters most. Our wedding restroom guide walks through bar timing and trailer sizing.
How many wheelchair-accessible units do you need?
Plan at least 1 wheelchair-accessible unit at every event. When portable toilets are grouped in a cluster, the 2010 ADA Standards, section 213.2, call for at least 5% of the units in each cluster to be accessible. Five percent of 24 units is 1.2, which rounds up to 2 accessible units.
Our wheelchair-accessible porta potty is designed to ADA dimensions, with a 60-inch turning space and grab bars. It has no sink inside. Pair it with a hand-washing station set on level ground nearby.
Read the rule text at the U.S. Access Board ADA Standards, section 213. Confirm with your permit office, venue or safety manager — this is not legal advice.
How many hand-washing stations should you add?
Add 1 two-sink hand-washing station for every 4 toilets when food is served or no indoor sink is open. The minimum is 1 station. Each station holds about 36 gallons of fresh water and serves about 400 hand washes per fill. Seven toilets ÷ 4 = 1.75, so plan 2 stations.
Put stations a few steps from the toilets, not beside the food line. Two sinks per station means two people wash at once. See our hand-washing station rental for specs.
In winter weeks below 28°F at night, station water can freeze. We may swap stations for sanitizer dispensers on those dates.
How many porta potties does a construction crew need?
OSHA 29 CFR 1926.51(c), Table D-1, requires 1 toilet for 20 or fewer workers. Above 20 workers, the minimum is 1 seat and 1 urinal per 40 workers. Jack Rental Works recommends 1 unit per 10 workers on a 40-hour week with weekly service, because the legal minimum fills tanks fast.
OSHA Table D-1 legal minimum
| Number of workers | Minimum facilities (OSHA 1926.51 Table D-1) |
|---|---|
| 20 or fewer | 1 toilet |
| 20 or more | 1 toilet seat and 1 urinal per 40 workers |
| 200 or more | 1 toilet seat and 1 urinal per 50 workers |
Our recommendation with weekly service
| Crew size | Standard units | Hand-washing |
|---|---|---|
| 1–10 | 1 | 1 station or sanitizer in unit |
| 11–20 | 2, or 1 with twice-weekly service | 1 station |
| 21–30 | 3 | 1 station |
| 31–40 | 4 | 1 station |
| 41–60 | 5–6 | 2 stations |
In Midland summers, highs run 95–105°F. We recommend twice-weekly service for crews of 10 or more from June through August. Our construction site toilet rental page covers weekly service and job-site placement.
Know your count? Get it on the truck.
Call (432) 239-8885 by noon Mon–Sat for same-day delivery in Midland and Odessa.
More questions about How Many Porta Potties Do I Need?
How many porta potties do I need for 30 people?
For 30 guests at an event up to 4 hours, 1 standard unit is enough. If the party runs longer than 4 hours, add 1 more unit. If you serve alcohol, add 1 more. For a 30-person party with a bar that runs 6 hours, plan on 3 units, with 1 of them wheelchair-accessible.
How many do I need for 80 guests?
Eighty guests for up to 4 hours need 2 standard units, since 80 divided by 50 rounds up to 2. A party past 4 hours adds 1 unit. A bar adds 1 unit. So an 80-guest evening party with drinks that runs 5 hours needs 4 units, plus 1 hand-washing station if food is served.
How many people does one porta potty handle?
One standard porta potty is rated by the manufacturer for about 200 uses between services. That is why our method plans 1 unit for every 50 guests over 4 hours. Each guest uses a restroom about once every 2 to 3 hours, and some margin keeps the line short and the unit clean.
How many hand-washing stations go with my toilets?
Add 1 two-sink hand-washing station for every 4 toilets when food is served or no indoor sink is open. The minimum is 1 station. Each station holds about 36 gallons of fresh water and serves about 400 hand washes per fill. A crew site also needs handwashing under OSHA 1926.51(f).
The fire marshal may require an accessible unit — can I add one later?
Yes. Call or text and we add a wheelchair-accessible unit to the same order. In Zones 1 and 2, an order placed by noon Mon–Sat can arrive the same day for a $75 rush trip. A later order arrives the next morning with no rush fee.
Why do other companies give different numbers, like 1 per 100?
Some rules of thumb count only short events with no alcohol. In our 2026 call review, callers said sizing advice from other companies was all over the place. Our method starts at 1 unit per 50 guests and adds for time, alcohol, and access, so the line stays short.
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