How many porta potties do I need for my event?
Plan 1 standard porta potty per 50 guests for an event up to 4 hours. Multiply by 1.5 for up to 6 hours, by 2 for up to 8 hours and by 2.5 past 8 hours, then round up. That is our dispatch rule from the Highway 60 yard, and it keeps lines short.
| Guests | Up to 4 hr | Up to 6 hr | Up to 8 hr | Over 8 hr |
|---|---|---|---|---|
| 25 guests | 1 | 1 | 1 | 2 |
| 50 guests | 1 | 2 | 2 | 3 |
| 75 guests | 2 | 3 | 3 | 4 |
| 100 guests | 2 | 3 | 4 | 5 |
| 150 guests | 3 | 5 | 6 | 8 |
| 200 guests | 4 | 6 | 8 | 10 |
| 300 guests | 6 | 9 | 12 | 15 |
| 500 guests | 10 | 15 | 20 | 25 |
The calculator above runs the same math. Not sure about hours? Count from when the first guest arrives to when the last one leaves.
Do I need more porta potties if alcohol is served?
Yes. Add 1 porta potty for every 4 units when beer, wine or a bar is served, rounding up. Drinking guests use the restroom more often, so a 150-guest, 6-hour reception goes from 5 units to 7. Busy bars and late-night dancing are where lines form first.
| Guests | Up to 4 hr | Up to 6 hr | Up to 8 hr | Over 8 hr |
|---|---|---|---|---|
| 50 guests | 2 | 3 | 3 | 4 |
| 100 guests | 3 | 4 | 5 | 7 |
| 150 guests | 4 | 7 | 8 | 10 |
| 200 guests | 5 | 8 | 10 | 13 |
| 300 guests | 8 | 12 | 15 | 19 |
How many wheelchair-accessible porta potties and handwash stations do I need?
Plan at least 1 wheelchair-accessible unit per restroom cluster and at least 5% of the total, never fewer than 1. California CBC 11B-213.2 uses that same 5% rule. When food is served, add at least 1 handwash station per 4 toilets. Most park and church events need both.
| Toilets on site | Wheelchair-accessible (≥5%, min 1) | Handwash stations if food (1 per 4, min 1) |
|---|---|---|
| 2 standard units | 1 | 1 |
| 4 standard units | 1 | 1 |
| 6 standard units | 1 | 2 |
| 10 standard units | 1 | 3 |
| 16 standard units | 1 | 4 |
| 24 standard units | 2 | 6 |
Accessible units need firm, level ground and a 7.5 × 7.5 ft footprint. The rule text is in the 2010 ADA Standards from the U.S. Access Board; confirm details with your venue. See the wheelchair-accessible porta potty and handwash station pages.
How many porta potties does Cal/OSHA require on a construction site?
Cal/OSHA 8 CCR §1526 requires 1 toilet per 20 employees, or fraction, of each sex on a construction site. Urinals may replace up to half the toilets, and a crew under 5 can share 1 single-occupancy unit. Our practical rule is 1 unit serviced weekly per about 10 workers on a 40-hour week.
| Workers of each sex | Toilets required (§1526) | Our practical count, 40-hr week |
|---|---|---|
| 1–4 | 1 single-occupancy unit allowed | 1 |
| 5–20 | 1 | 1–2 |
| 21–40 | 2 | 3–4 |
| 41–60 | 3 | 5–6 |
| 61–80 | 4 | 7–8 |
Read the rule at dir.ca.gov — 8 CCR §1526. The legal floor and a comfortable crew are not the same number. We explain why in our Cal/OSHA portable toilet rules guide.
How many toilets do warehouses, offices and farm crews need?
Permanent workplaces follow Cal/OSHA §3364: 1 toilet for 1–15 employees, 2 for 16–35, 3 for 36–55 and up from there. Farm crews follow §3457: 1 toilet and 1 handwash station per 20 workers, within a quarter mile or 5 minutes' walk, whichever is shorter.
| Employees | Toilets required (§3364) |
|---|---|
| 1–15 | 1 |
| 16–35 | 2 |
| 36–55 | 3 |
| 56–80 | 4 |
| 81–110 | 5 |
| 111–150 | 6 |
| Over 150 | Add 1 per 40 |
| Field workers | Toilets | Handwash |
|---|---|---|
| 1–20 | 1 | 1 |
| 21–40 | 2 | 2 |
| 41–60 | 3 | 3 |
| 61–80 | 4 | 4 |
Sources: 8 CCR §3364 and 8 CCR §3457. Cherry Valley and Oak Glen orchard crews spread out, so we often split units between rows. See farm and ranch porta potty rental.
Got your number? Lock in the units.
Read us the calculator result and your address. The dispatcher checks the count, then texts an itemized quote in about 15 minutes.
How many porta potties for a half-marathon with a start/finish and aid station?
For a half-marathon with 400 runners and 200 spectators over 4 hours, plan 12 standard units, 1 wheelchair-accessible unit and 3 handwash stations at the start/finish. Add 2 standard units and 1 wheelchair-accessible unit at each aid station. Put most units near the start line, where pre-race lines form.
- Start/finish math600 people ÷ 50 = 12 units for up to 4 hours. Accessible: 5% of 12 = 0.6, so 1. Food at the finish: 12 ÷ 4 = 3 handwash stations.
- Aid stationOur suggestion is 2 standard units plus 1 accessible unit per cluster, placed off the course on firm ground.
- Place for flowKeep units 1–2 minutes' walk from the corral, doors facing away from the course and the wind.
- Truck accessEach cluster needs a spot our truck can reach before road closures start. Send a GPS pin for every cluster.
How many restrooms does an evacuation shelter need?
A 463-evacuee shelter running around the clock needs about 24 standard units, 2 wheelchair-accessible units and 6 handwash stations by our rule. That is 463 ÷ 50 = 9.26, times 2.5 for over 8 hours, rounded up. Plan daily service, because shelters run 24 hours a day.
- Base count463 ÷ 50 = 9.26 × 2.5 = 23.15, round up to 24 standard units.
- Accessible5% of 24 = 1.2, round up to 2 wheelchair-accessible units.
- Handwash24 ÷ 4 = 6 handwash stations. Shelters serve food, so these are not optional.
- TrailersRestroom trailers can replace some units if the site has 120V power and a hose. We size trailers by stalls on the call.
- ServiceDaily pump-outs at minimum. Tell us when the shelter opens and the crowd peaks.
The 2020 Apple Fire evacuated 7,800+ people from Cherry Valley, Banning Bench and Oak Glen. Our emergency restroom rental page covers same-day shelter setups.