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What size propane tank do I need?

Check the appliances you want to run. We will work out your total gas load, the tank size that suits it, and roughly how often you would need a fill.

Step 1

What do you want to run on propane?

Check everything you have now or plan to add. Use the arrows if you have more than one.

Step 2

A couple of details

This is our main heat and hot water
Tick if propane runs the house year-round rather than a few features. I want the tank buried
Underground tanks start at 250 gallons.

Your result

Pick an appliance

Your total load decides the tank, not the size of your house.

Total gas load	—
Usable propane	—
Typical time between fills	—
Generator runtime	—

Request a Free Estimate

An estimate, not a quote. The final size is confirmed at your property site visit — where the tank can legally sit, how far the line runs, and what your appliances actually draw.

How this works

Why load matters more than square footage

Propane tanks are sized on two things: how much gas your appliances demand at once, and how long you want to go between fills. A tank that is too small cannot vaporize fast enough on a cold morning when the pool heater and the tankless both fire — you get appliances starving, not an empty tank. A tank that is too large just costs more and sits half full.

Tanks fill to 80%, so a 500 gallon tank holds about 400 usable gallons. Propane carries roughly 91,500 BTU per gallon. We size for your peak demand first, then check that the fills land at a sensible interval.

Shape matters too. A 120 gallon lying on its side has more of its wall in contact with liquid propane than the same 120 gallons standing up, so it can vaporise faster and feed a heavier draw. Same fuel, same fills — different capability.

120 gal vertical420 lb cylinder. Small footprint, tucks against a wall. One or two light appliances.

120 gal horizontalSame capacity lying down. More surface in contact with the liquid, so it keeps up with a bigger draw.

250 galSmall whole-home, or a pool heater on its own.

500 galThe common one. Whole home, generator, pool heat.

1000 galLarge estate, heavy simultaneous load, or commercial.

Next step

Want it confirmed on your property?

A free estimate first, then we come out and walk the property with you before anything is ordered.

Request a Free Estimate

Call us Free estimate