Propane Tank Sizes
A propane tank is named for its water capacity, not the
amount of propane it holds. Every tank is filled to 80% of its rated
capacity, so a 500 gallon tank holds about 400 gallons of propane. The
remaining 20% is deliberate vapour space: propane is stored as a liquid under
pressure and expands as temperature rises.
Plan your consumption against the usable figure in the table below, not the
name on the tank.
Propane tank sizes at a glance
These are the dimensions and weights of tanks we actually hold in stock,
taken from the manufacturer specifications rather than generic figures. Most
are Quality Steel Corp ASME tanks.
| Rated size | Usable propane | Dimensions | Empty weight | Typically supports |
|---|---|---|---|---|
| 24 gallon (100 lb) propane tank | ~19 gal | 18″ W × 29.8″ H × 18″ D | 85 lb | A single appliance — range, fireplace, or a small heater |
| 420 lb Propane Tank | ASME | ~96 gal | 30″ W × 54″ H × 30″ D | 278 lb | Two or three appliances; hot water plus cooking |
| 250 Gallon Above Ground Propane Tank | ~200 gal | 30″ × 92″ | 480 lb | Supplemental heat, or a small home on propane |
| 500 Gallon Propane Tank | ~400 gal | 37″ × 120″ | 940 lb | Whole-home heat, roughly 2,500–4,500 sq ft |
| 1,000 gallon propane tank | ~800 gal | 41″ × 190″ | 1,800 lb | Large homes, agricultural and light commercial use |
Shop by size: 500 Gallon Underground Propane Tank | ASME, New · 1000 Gallon Above Ground Propane Tank | ASME · Used 500 Gallon Propane Tank · Used 250 Gallon Propane Tank · 320 Gallon Horizontal Propane Tank | ASME · 57 Gallon Propane Tank | Vertical · 120 Gallon Vertical Propane Tank | ASME
We also stock 1,500 and 2,500 gallon tanks, and industrial storage from
10,000 gallons up — see all
propane tanks
for sale for current stock and pricing.
Vertical or horizontal?
The smaller sizes are vertical cylinders — the 24 and
120 gallon tanks stand upright on a compact footprint, which is why they suit
tight spaces and single appliances. From 250 gallons up, tanks are
horizontal: a 1,000 gallon tank is nearly 16 feet long, so the
space it needs is measured in yards, not inches. Check the run before you
choose the size.
Which size do I need?
The honest answer is that it depends on how many appliances run on propane
and whether it heats the house. As a starting point:
- One appliance — a grill, range or fireplace:
24 or 120 gallon. - Several appliances, but not primary heat — hot
water, cooking, a dryer: 120 or 250 gallon. - Propane is your primary heat — 500 gallon is the
standard choice for most homes. - Large property, farm, or a standby generator —
1,000 gallon, so you are not refilling mid-winter or mid-outage.
Two practical points. Refill economics favour the larger tank: fewer
deliveries, and you can buy when prices are lower rather than when you are
empty. But an oversized tank costs more up front and takes more space, so the
usual advice is to size for your heating load and let the other
appliances come along with it.
Above ground or underground?
Above ground tanks cost less to install, are simpler to inspect and easier
to service. Underground tanks cost more to install but are out of sight and
less affected by ambient temperature swings.
The distinction matters at purchase: a tank must be built for the
installation you intend. Above ground tanks are painted; underground tanks are
coated for burial and usually fitted with a riser. Some of our tanks are rated
for both. An above ground tank must never be buried.
Common questions
How much propane does a 500 gallon tank hold? About 400
gallons. Tanks are filled to 80% of rated capacity to allow for thermal
expansion of the liquid propane.
How big is a 500 gallon propane tank? The 500 gallon tanks
we stock measure 37 inches in diameter by 120 inches long and weigh 940 lb
empty.
What size propane tank do I need for a house? If propane is
your primary heat source, 500 gallon is the usual choice for a home of roughly
2,500 to 4,500 sq ft. For supplemental heat or a few appliances, 250 gallon is
generally enough.
Is a 420 lb propane tank the same as a 120 gallon tank?
Yes. Smaller tanks are often named by the weight of propane they hold rather
than water capacity — a 420 lb tank is a 120 gallon tank, and a 100 lb
tank is 24 gallon.
Do I need a permit to install a propane tank? Usually yes,
and requirements vary by jurisdiction. Setback distances from buildings and
property lines are set by local code and NFPA 58. Check with your local
building or fire authority before installation.