How Many Gallons of Propane Are in a 20 Pound Tank?

If you’re shelling out cash for propane, you might want to know how much of it you’re actually getting. Most people buy propane by the pound, using commercially available 20-pound tanks. How many gallons is in one of those tanks?

I get this question a lot, so we decided to make a quick video showing you exactly how much propane is in a 20-pound tank.

A 20-pound propane tank contains 4.6 gallons of propane.

That’s a lot of propane, and it should last you for quite a while if you’re using it for things like grilling or heating with a patio heater.

Varying Sizes of Propane Tanks

Of course, propane tanks come in different sizes, so if you’re not sure how much propane you need, it’s always a good idea to check with your local retailer or propane supplier. They can help you determine the right size tank for your needs.

Keep in mind, too, that some tank exchange companies sell 20-pound capacity tanks, but only fill them to 15 pounds. Check the label to know exactly what you’re buying, and don’t assume that your 20-pound capacity tank actually includes 20 pounds of propane!

In some cases, this is a safety issue. Filling the tank beyond about 16 pounds might leave it overfull, especially if it heats up. For that reason, some companies don’t fill beyond 15-16 pounds.

Is a 20 lb propane tank 5 gallons?

Not quite! Again, a 20 pound propane tank has about 4.6 gallons in it when full. You could round up and say five gallons, but really it’s a bit less than 5.