How Much Does It Cost To Fill 20 Lb Propane Tank?

The cost to fill 20 lb propane tank depends on the cost of refill, which is around $3 or $4 per gallon. Since a 20 lb tank holds around 4.7 gallons of propane, this accounts for a cost of approximately $14 to $20. Many stores offer the service of exchanging propane tanks, which many people find advantageous. This would cost about $20, and the filling will save around $8. If you are wondering how much to fill a propane tank, then this is not the only answer. There are more factors that you need to consider before you make the final choice.

Price Factors of Filling a 20lb Tanks


Even though the 20 lb propane tank refill cost would be calculated be per gallon, some factors would affect this price. The following are these considerations that would cause variations in the costs of propane tanks.

  • Some propane suppliers may not fill the tank completely. They would only fill it up to around 15 lb and charge for the whole 20 lb. These suppliers are highly disadvantageous.
  • If you go for exchange, the costs will be slightly higher than refilling it.
  • Filling the tanks before they are entirely empty would reduce the cost. This is because some gas is left in the tank and would contain only a lesser amount when refilled.
  • When temperature increases, the gas expands, creating less room for the gas to be filled. This mostly occurs in warm seasons.

The Effect of Temperature

As the gases expand with rising temperatures, the real amount of propane filled could be reduced by 1 or 2 pounds in hot climates. If the environment is cooler, then more gas can be held by the tank. Some suppliers are even reluctant to fill tanks in colder climates. So you can figure out their purpose behind this and choose to pay less for what they call a “full” tank because the actual content may be lower than the real capacity. 

Don’t Overfill

Propane tanks are filled only up to 80% of their capacity. Even though the tanks can hold 20% more than the designed amount of 20 lb propane tank, it is not recommended to fill beyond the limit of 20 lb. This extra room is necessary for the gas to expand upon temperature changes. Overfilling propane into a tank in the colder season and bringing it into a warmer environment would make the gas expand. Since there is no adequate room for this gas expansion within the tank, some gas would be released into the air through the tank’s pressure relief valve. This would once again create a loss.

Be Aware of Sales

There may be sales where they would claim to sell a full tank for a specific price. However, here again, the amount they consider as full might depend on the sellers. If it may appear cheaper, then there is a high risk of getting few gallons lesser than the amount it holds. So be aware of these fraudulent sellers when you encounter sales with these reduced prices.

Is It Cheaper to Refill Propane or Exchange?

The decision of whether you should exchange or refill needs to be determined by the facts of how much you spend on buying your own propane tank and the amount of gas consumed throughout the year. Generally, the 20 lb propane tank refill cost is cheaper by $1.76 per gallon than exchanging. The cost to fill 20 lb propane tank is around $3 or $4, while the exchanging costs are around $5 or $6 per gallon. But most of the exchangers fill only 15 lb of propane for the 20 lb tanks.

This is a greater disadvantage since you may be charged for a full tank while not getting an actual full tank of propane. This would make you have to exchange your tank very often. So you can either choose the convenience of exchange or have the benefits of saving money by properly consuming the right amount of propane.

Most people exchange their gas tanks well ahead of time before they are completely empty. Since the tank is given away before being fully drained, it is a clear disadvantage for the user. Even though it’s the personal choice of the consumers, they are sure to lose a huge amount of money through this practice. 

Is Propane Cheaper if You Have Your Own Tank?

If you are a frequent buyer, then you can save a lot of expense if you own a tank. You can pay a lower rate per gallon, and most importantly, you can have control of the amount you fill into your tank. Even if you have propane left in your tank when refilling, you can refill accordingly and save money. On the other way around, if you don’t need propane so often, then owning a tank would not be worth it. Exchanging would cost only a little more, and you won’t save much as you rarely purchase. You can even save the expense of buying a tank.

How Much Does a 20 LB Propane Tank Cost?

An empty 20 lb propane tank would cost about $35 to $60. The costs may vary depending on the brand, quality, and other features. If the tank comes with a built-in gas meter gauge, then it will increase the price by about $20. But this may cause trouble in long-term use as refilling very often causes problems. You can purchase a 20 lb propane tank with a built-in gauge feature at a big box store even get it delivered from online suppliers. It is beneficial to buy this type of tank if you are planning on purchasing a tank than exchanging.

Frequently Asked Questions

How Many Hours Does a 20 Pound Propane Tank Last?

20 lb propane tank would last for about 18 to 20 hours when a medium-sized grill is used. If a large grill is operated, then the tank usage can be expected for up to 10 hours only.

How Many Gallons of Propane in a 20 LB Tank?

The amount that a 20 lb propane tank can hold is 4.7 gallons. The weight of propane is 4.24 pounds per gallon. So if you need the weight of the propane tank, it is the reverse calculation of 4.24 × 4.7, which gives you 20 lbs. 

How much does a full 20 lb propane tank weigh?

Together with the weight of the tank and propane, the total weight is around 37 lb.

Does propane go bad?

Propane has no expiration date, unlike some other fuel sources such as kerosene, diesel, and gasoline that degrade over time. However, it is necessary to consider the condition of the propane storage tanks when storing them for a long time.

Which is cheaper, propane or natural gas?

Even though propane is usually more expensive than natural gas, it produces about twice the amount of heat as given by natural gas. Natural gas may be more economical in certain areas, while propane cost is cheaper in other areas. However, both these fuel types are comparatively less costly than electricity.

Why is propane so expensive?

Propane is produced from crude oil refining and by processing natural gas. The price is mostly influenced by the cost of crude oil. When inventories of propane are low at the beginning of a season, then there is a high possibility that the prices may increase into the season. 

What is done with expired propane tanks?

If the propane tank is drawing close to its date of expiration, then it’s better to swap it with a new tank. You can exchange your old tank and get a new tank filled with propane. The recertification process would cost around $35 to $60. Tanks that have passed their normal date of expiration can be recertified by a person trained for the task. They would inspect the tanks, and if they see that the tanks are in good condition to be used further, they will mark an “E” on the tank in front of the date of manufacture. This indicates the extension of the life of the tank by another 5 years.

Where can I fill my propane tank for a grill?

The liquid propane tank used to provide gas to an outdoor gas grill can be purchased from any store, such as local hardware stores, big-box home improvement centers, and even larger grocery stores. They can also be purchased from mass merchandise centers, such as Walmart or Costco.

Can Propane tanks explode?

Propane is highly explosive, but there is a very low possibility for a propane LPG tank explosion. Propane tanks or gas cylinders can explode, but not so easy. It is very difficult for a propane tank to get exploded.


Do not attempt to refill a propane tank on your own simply to save money. Even though there are many tutorials that guide you through this process, undertaking this risk is not worth saving a few dollars. If something goes wrong, there is a high risk of causing harm to yourself and even death. Read more about troubleshooting home appliances.

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