How Long Does A 500-Gallon Propane Tank Last? (Calculated)

Of all the residential propane tank sizes, the 500-gallon propane tank is the most common one. When the winter weather hits, you should at least have an idea of how long does a 500-gallon propane tank last for a house.

Here’s the deal:

A 500-gallon propane tank can last anywhere from 1 month and 23 days to 14 months and 4 days. For exact time, check the chart and graph for different sizes of homes further on.

500 gallon propane tank
500-gallon tank is a residential propane tank for houses. It can be installed underground, in the basement or even in a large garage.

An average US household consumes about 750 gallons of propane per winter. That means an average US household will need about 2 full fills of 500-gallon propane tank per winter (500-gallon tank holds a maximum of 400 gallons of propane; the 80% safety rule).

How Long Does A 500-Gallon Propane Tank Last For A House
On average, a US household will burn through 750 gallons of propane every winter. Data Source: US Energy Information Administration

We will have a closer look at the lifetime of a 500-gallon tank. This will enable us to more precisely figure out how long will 500 gallons of propane last in houses with square footage ranging from 500 sq ft to 4,000 sq ft.

To figure out exactly how long does a 500-gallon propane tank for your house, we need to take into account these key parameters:

  • Size of your house. Bigger houses require more heating; 500-gallon propane tank will run out sooner than in the case of smaller houses.
  • Heating requirements (location). Houses in the North US require higher BTU heating output than houses in the South US. Example: The 500-gallon propane tank will last longer in Texas than in Chicago.
  • How harsh is the winter? In harsh winters we will burn more propane than in mild winters. As we can see from the data for average US household winter consumption for the period from 2010 to 2016 above, the 2013-2014 winter was the harshest and we burned 830 gallons of propane on average vs. 750 gallons of propane on a standard winter.
  • Energy efficiency of your propane-powered heating devices. High energy-efficiency propane furnaces with above 90 AFUE rating, for example, will spend less propane for the same heating output than 70 AFUE rating furnaces. That means a 500-gallon propane tank will last longer.
  • 80% max. propane tank rule.

How Much Propane Do We Burn Per Winter? (Size Of Home)

As you can see from the EIA data, an average US household burns about 750 gallons of propane every winter. We also know that an average single-family house square footage is about 2,200 sq ft (Data from Statista; period 2010-2019).

We can calculate how many gallons of propane we burn during the winter per square feet:

750 Gallons Of Propane ÷ 2,200 Sq Ft House = 0.34 Gallon Of Propane Per Sq Ft

Based on this, we can calculate the average winter propane usage for different home sizes (these are rough average estimates):

Home Size (Square Footage): Propane Consumption (In Gallons):
500 sq ft 170 Gallons
1,000 sq ft 340 Gallons
1,500 sq ft 510 Gallons
2,000 sq ft 680 Gallons
2,500 sq ft 850 Gallons
3,000 sq ft 1,020 Gallons
3,500 sq ft 1,190 Gallons
4,000 sq ft 1,360 Gallons

Now we know how many gallons of propane different size homes will, on average, burn throughout the winter. We can use this data to calculate how long will 500-gallon propane last:

How Long Does A 500-Gallon Propane Tank Last For Different Home Sizes

First of all, we need to figure out how many gallons of propane does a 500-gallon propane tank actually hold. Instinctively we think it’s 500 gallons; it’s actually 400 gallons.

We only fill propane tanks up to 80% of their respective full volumetric capacity. That is done for safety reasons. If a propane tank is heated, the propane would expand and create pressure on the outer layers of the tank.

That means that a full 500-gallon tank holds 400 gallons of propane. Its totally energy content is 36,600,000 BTUs (100% efficiency).

Before we look at the table of how long will a 500-gallon tank last for different sizes of homes, let’s look at an example of how you can calculate that.

Example: How long does a 500-gallon propane tank last for a 1,500 sq ft house?

Based on average estimations, we know that a 1,500 sq ft will burn through 510 gallons of propane in 6 winter months. We also know that a full 500-gallon tank contains 400 gallons of propane. Here’s how we can calculate that:

  • 510 gallons of propane will last for 6 months.
  • 400 gallons (full 500-gallon tank) will last for how many months?

400 Gallons × 6 Months ÷ 510 Gallons = 4.706 Months

That means that a full 500-gallon propane tank will last for 4 months and 6 days in a 1,500 sq ft home.

We can use this principle to calculate after what time the 500-gallon tank will be empty for different home sizes:

500-Gallon Tank Longevity Chart

House Size (Square Footage): How Long Will A 500-Gallon Propane Tank Last?
500 sq ft 14 Months and 4 Days
1,000 sq ft 7 Months and 2 Days
1,500 sq ft 4 Months and 6 Days
2,000 sq ft 3 Months and 25 Days
2,500 sq ft 2 Months and 25 Days
3,000 sq ft 2 Months and 11 Days
3,500 sq ft 2 Months and 1 Day
4,000 sq ft 1 Month and 23 Days

Here is a graphic representation of these numbers:

how long will a 500 gallon propane tank last for a house

Now, these are just estimations, based on statistic averages.

An important factor that can increase or decrease the specified time how long will a 500-gallon propane tank last is the energy efficiency of your propane-powered appliances. That usually means a propane furnace.

High energy efficiency propane furnaces (with above 90 AFUE rating) will require less propane for the same heating output. These superb units can prolong the time how long does a 500-gallon propane tank last for up to 25%.

You can read our entire article about how long do propane tanks last (any tank from 1 lb to 1,000-gallon tank) here. If you’re deciding between 500-gallon vs 100-gallon, 250-gallon, or 1,000-gallon propane tank, you can check how similar calculation for:

If you have any questions about the calculations or the longevity of 500-gallon propane tanks, you can use the comments below and we’ll try our best to help you out.

8 thoughts on “How Long Does A 500-Gallon Propane Tank Last? (Calculated)”

    • Hello Mikesha, your average gas stove uses anywhere from 20 to 50 gallons of propane per year (depends on the usage, of course). To store that propane, you can use pretty much any tank: 100 gallon, 250 gallon, or 500 gallon. Hope this helps.

  1. Hello. We have a 3200sqft home with heating, clothes dryer and cooking on that tank. Located in PA. How long with the 500gallong tank last?

    • Hello Neel, if you take into account the average consumption, you are likely to burn 1,088 gallons of propane per year. A 500-gallon tank holds 400 gallons of propane. This should be enough, presuming average day-to-day consumption, for 4 months or so.

  2. Trying to figure out my 17kw propane generator run time per tank. I took the total btus given and divided by 250k btus to get 6.1 days of run time.

    If true, a 500g tank isn’t a bad choice, since the generator is the only thing on it.

    • Hi Nathan, alright, the key data point is how efficient is a propane generator. As we have an article about generator cost per kWh about this here; roughly speaking, propane generator has a 20% efficiency.

      500 gallon propane tank contains 400 gallons of propane; that contains 36,600,000 BTU of heat content (if we assume 100% efficiency). Realistically, a propane generator with 20% efficiency can extract 7,320,000 BTU from all that propane.

      17kW propane generator when running at 100% output will require 17kW * 3,412 BTU/kW / 0.2 = 290,020 BTU per hour to run. 1 gallon of propane contains 91,500 BTU. That means that 17kW propane generator is chugging 290,020 BTU / 91,500 BTU/gallon = 3.17 gallons of propane per hour.

      Alright. We have 400 gallons of propane in a 500 gallon propane tank, and generator is chugging 3.17 gallons per hour. That means the tank will run this generator at 100% output for 400/3.17 = 126.58 hours. That’s 5 days and about 7 hours. So, your calculation is actually quite on point.

      Of course, if you run the generator in quarter, half, or three quarters load, the 500 gallon propane tank will last longer. Hope this helps.


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