Propane Tank Size Comparison Guide
Choosing the right propane tank size is essential for balancing convenience, cost, and adequate fuel supply. Tanks that are too small require frequent refilling and risk running empty during peak demand, while oversized tanks cost more to install and may incur higher rental fees without any practical benefit. This guide covers all seven standard propane tank sizes from portable 20-pound cylinders to commercial 2,000-gallon bulk tanks, helping you select the optimal size for your specific propane usage pattern.
The most important factor in tank selection is your total annual propane consumption. Use our propane usage calculator to estimate your annual gallons based on your specific appliances and state, then match that consumption to the appropriate tank size below. Remember that propane tanks are filled to only 80% of their total capacity as a safety measure, so a 500-gallon tank holds a maximum of 400 usable gallons per fill.
Beyond capacity, consider delivery logistics, installation requirements, and cost. Portable tanks (20 lb and 100 lb) can be transported by the homeowner for refilling. Residential tanks (120 to 500 gallon) require professional delivery by a propane truck. Large tanks (1,000 to 2,000 gallon) offer bulk purchasing discounts but require significant installation space and may need underground placement. Most propane companies offer tank rental or lease programs as an alternative to purchasing.
Tank Size Quick Reference
| Tank Size | Capacity | Usable (80%) | Dimensions |
|---|---|---|---|
| 20 lb Tank (4.7 Gallons) | 4.7 gal | 3.8 gal | 18 inches tall x 12 inches diameter |
| 100 lb Tank (23.6 Gallons) | 23.6 gal | 18.9 gal | 48 inches tall x 14.5 inches diameter |
| 120 Gallon Tank | 120 gal | 96 gal | 52 inches long x 30 inches diameter |
| 250 Gallon Tank | 250 gal | 200 gal | 92 inches long x 30 inches diameter |
| 500 Gallon Tank | 500 gal | 400 gal | 120 inches long x 37 inches diameter |
| 1,000 Gallon Tank | 1,000 gal | 800 gal | 190 inches long x 41 inches diameter |
| 2,000 Gallon Tank | 2,000 gal | 1,600 gal | 288 inches long x 48 inches diameter |
20 lb Tank (4.7 Gallons)
Portable use for gas grills, patio heaters, camping, and small appliances. The most common consumer propane container, available at hardware stores, gas stations, and grocery stores. Can be refilled or exchanged at thousands of locations nationwide.
View full details →100 lb Tank (23.6 Gallons)
Portable use for construction heaters, larger grills, multiple outdoor appliances, and temporary heating. Often used on job sites, food trucks, and for heating small spaces. Can be transported by the homeowner and refilled at propane dealers. Provides significantly more capacity than the 20 lb tank without requiring a permanent installation.
View full details →120 Gallon Tank
Small residential installations for homes with modest propane needs such as a water heater and cooking range only. Often installed at vacation homes, small cottages, or as supplemental supply for a single propane appliance. Requires professional installation and delivery service. Typically filled to 80% capacity (96 usable gallons) per safety regulations.
View full details →250 Gallon Tank
Standard residential tank for homes using propane for water heating, cooking, and clothes drying. The most common above-ground residential tank size. Provides adequate capacity for year-round non-heating propane use with deliveries 2-4 times per year. Also suitable for homes with moderate heating needs in mild climates.
View full details →500 Gallon Tank
Large residential tank for homes using propane as their primary heating fuel plus additional appliances. The standard choice for whole-house propane including furnace, water heater, cooking, and clothes dryer. Available in above-ground or underground configurations. Underground installation preserves yard aesthetics but costs more. Typically requires 2-4 deliveries per year depending on climate and usage.
View full details →1,000 Gallon Tank
Commercial and large residential installations. Ideal for large homes in cold climates with extensive propane use including heating, hot water, cooking, pool heating, and backup generators. Also used for small commercial buildings, agricultural operations, and multi-unit residential properties. Fewer deliveries needed per year reduces delivery costs and ensures supply security during peak demand winter months.
View full details →2,000 Gallon Tank
Commercial and industrial installations. Used for large commercial buildings, agricultural operations with multiple buildings, resort and hospitality properties, and communities with shared propane systems. Can also serve multiple residential units from a single tank. The large capacity reduces delivery frequency and provides bulk purchasing advantages. Usually installed underground due to the significant footprint.
View full details →How to Choose the Right Tank Size
The primary consideration is matching your tank capacity to your consumption pattern so that you do not run out of propane between scheduled deliveries. As a general guideline: homes using propane only for cooking and water heating (under 200 gallons per year) can use a 120-gallon tank. Homes with moderate use including clothes drying and a fireplace (200-500 gallons per year) should choose a 250-gallon tank. Homes using propane as the primary heating fuel (500-1,000 gallons per year) need a 500-gallon tank. Large homes in cold climates or those with pool heaters (over 1,000 gallons per year) benefit from a 1,000-gallon tank.
Delivery frequency matters because each propane delivery incurs a base fee that gets spread across the gallons delivered. Larger tanks mean fewer deliveries per year and lower per-gallon delivered costs. Most propane companies prefer to deliver a minimum of 100-150 gallons per trip to keep their delivery economics viable. With a 250-gallon tank, you might need 3-4 deliveries per year, while a 500-gallon tank typically needs only 2-3 deliveries. Fewer deliveries also reduce the risk of running empty during winter storms when delivery trucks may be delayed.
Consider future plans as well. If you might add a propane fireplace, pool heater, or standby generator in the coming years, choosing a tank one size larger than your current needs avoids the expense and disruption of swapping tanks later. The incremental cost of a 500-gallon tank versus a 250-gallon tank is relatively small compared to the cost of removing and replacing a tank installation.
Tank Ownership vs Rental
Propane companies offer two models for tank provisioning: purchase and rental. Purchasing a tank outright gives you the freedom to buy propane from any dealer, which allows you to shop for the best price. Owned tanks also have no monthly rental fees. However, you are responsible for maintenance, painting, and eventual replacement. Tank purchase prices range from $400-800 for a 120-gallon tank to $2,000-3,500 for a 500-gallon tank, plus installation costs.
Renting or leasing a tank from your propane dealer eliminates the upfront purchase cost and transfers maintenance responsibility to the company. Monthly rental fees typically range from $25-75 per month depending on tank size and location. The trade-off is that you must buy propane exclusively from the company that owns the tank, which limits your ability to comparison shop. Some rental agreements also include minimum annual purchase requirements and early termination fees.
For most homeowners who plan to stay in their home for more than 3-5 years, purchasing a tank and buying propane on the open market provides the lowest total cost over time. For short-term residents, renters, or those who prefer to avoid maintenance hassles, renting is the simpler option. Always read the full rental agreement before signing, paying attention to termination clauses, minimum purchase requirements, and who pays for repairs.