★ COMPARISONS · PROPANE VS NATURAL GAS · 2026
At 40,000 BTU/hr, propane costs $1.75 an hour ($174.86 a year) and piped natural gas costs $0.64 an hour ($64.00 a year) — natural gas wins by $110.86 a year, but the $800 gas line takes 722 cooking hours to repay. This one is the PROPANE-VS-NATURAL-GAS comparison — the same grill type on two gas supplies, tank propane against piped natural gas — the gas-grill-vs-charcoal-grill page is the GAS-VS-CHARCOAL comparison — gas against charcoal fuel cost — not two gas supplies; the gas-vs-electric-grill-calculator page is the GAS-VS-ELECTRIC tool — a gas grill against an electric grill over 5 years — not two gas supplies.
Put your burner size, fuel prices, install cost and cooking hours in: 40,000 BTU/hr at $4.00 a gallon vs $1.60 a therm is $1.75 an hour for propane and $0.64 for natural gas. The install, not the fuel price, is the decision.
It means that, at 100 cooking hours a year, piped natural gas costs $110.86 less than tank propane — $64.00 against $174.86. The gap is $1.11 an hour: propane costs $1.75 an hour and natural gas costs $0.64. But the gas line costs $800 to run, and the saving only repays it after 722 cooking hours — about 7.22 years at 100 hours a year. So the comparison has two answers: per hour, natural gas wins from the first cook; counting the install, it wins only if you grill long enough for 722 hours. At 200 hours a year the break-even is still 722 hours, but it arrives in 3.61 years instead.
Propane costs more per BTU than piped natural gas. A gallon of propane holds 91,500 BTU and costs $4.00, so a million BTU of propane costs $43.72; a therm holds 100,000 BTU and costs $1.60, so a million BTU of natural gas costs $16.00. Propane is nearly three times the price per unit of heat, and the grill burns the same BTUs either way — the fuel is the only difference. That is why natural gas wins at every burner size here: a 30,000 BTU/hr burner saves $83.15 a year and a 60,000 BTU/hr burner saves $166.30. The bigger the grill, the bigger the saving, because the per-hour gap grows with the burner.
The install is the whole question. At $800 and $1.11 saved an hour, the break-even is 722 hours — 7.22 years at 100 hours a year, 3.61 years at 200. At a $1,500 install the break-even is 1354 hours, 13.53 years at 100 hours a year. If the gas line is already in — a $0 install — there is no break-even to wait for and natural gas wins from the first hour. If you grill twice a month, the line may never pay for itself; if you grill every weekend, it pays in a few years.
The prices move, and the tie is a long way off. Propane at $3.00 a gallon instead of $4.00 narrows the saving to $67.15 a year, and natural gas at $2.00 a therm instead of $1.60 narrows it to $94.86 — but neither flips the winner. Propane would have to fall to $1.464 a gallon to tie, below the EIA bulk average of $2.69, and natural gas would have to rise to $4.3716 a therm, far above the $1.30 to $1.65 residential range. The winner is not close: check your own prices in the calculator, but expect natural gas to win on fuel and the install to decide the rest.
On the defaults: a 40,000 BTU/hr burner, propane $4.00 a gallon, natural gas $1.60 a therm, $800 install, 100 cooking hours a year.
And the other way: propane at $1.464 a gallon ties natural gas at $1.60 a therm exactly, natural gas at $4.3716 a therm ties propane at $4.00 a gallon (the two sit $0.00 apart over a year at that price — essentially a tie, because the price is rounded to 4dp), and 722 cooking hours is the smallest whole number that repays the $800 install.
The defaults are a 40,000 BTU/hr burner — a typical 3-burner grill with all burners on — propane at $4.00 a gallon, natural gas at $1.60 a therm, an $800 gas-line install, and 100 cooking hours a year, about 2 hours a week. The propane price is the tank-exchange level: a 20-lb grill tank holds about 4.7 gallons and an exchange or refill runs $12 to $20, so $4.00 a gallon is the illustrative grill-tank price. The EIA residential propane average was $2.689 a gallon for the week ending October 19, 2026 — but that is bulk delivery to a home tank, not a grill cylinder, and it is cited on the page alongside the default. The natural gas price is the illustrative delivered residential level: the EIA 2026-27 Winter Fuels Outlook puts residential natural gas at $13.44 per Mcf, about $1.30 a therm, and typical residential rates run $1.45 to $1.65 a therm. The model assumes the same grill and the same burner on both fuels, so the heat output is identical and only the fuel price differs — it does not count a monthly gas service charge, tank rental, or the cost of the grill itself. The break-even counts cooking hours only: 722 hours is the smallest whole number of hours whose saving reaches the $800 install, and the years divide those hours by the hours a year you grill.
These notes repeat in every explainer section because this page is built to be read start to finish: propane costs more per BTU than piped natural gas; the install is the whole question; and the prices move, and the tie is a long way off.
| Output | Formula | What it means |
|---|---|---|
| Propane per hour | BTU/hr × $/gal ÷ 91,500 | $1.75 — 40,000 × $4.00 ÷ 91,500. |
| Natural gas per hour | BTU/hr × $/therm ÷ 100,000 | $0.64 — 40,000 × $1.60 ÷ 100,000. |
| Propane per year | per hour × hours a year | $174.86 — $1.75 × 100. |
| Natural gas per year | per hour × hours a year | $64.00 — $0.64 × 100. |
| Winner (a year) | lower annual cost wins | Natural gas by $110.86 — $174.86 vs $64.00. |
| Break-even hours | install ÷ saving per hour | 722 hours — $800 ÷ $1.11. |
| Break-even years | break-even hours ÷ hours a year | 7.22 years — 722 ÷ 100. |
| Reverse: Propane price tying the two fuels | step | $1.464 a gallon: Propane $0.64 an hour ($64.00 a year) — natural gas $0.64 an hour ($64.00 a year). An exact tie — both fuels cost the same a year. Break-even does not apply — the two fuels cost the same per hour, so the install is never repaid. |
| Reverse: Natural gas price tying the two fuels | step | $4.3716 a therm: Propane $1.75 an hour ($174.86 a year) — natural gas $1.75 an hour ($174.86 a year). Propane wins by $0.00 a year. The install never breaks even — natural gas costs more per hour than propane. |
| Reverse: Break-even cooking hours for the install | step | 722 hours: After 722 cooking hours the saving is $800.43 against the $800.00 install — the install is covered, by $0.43. |
| 30,000 BTU/hr burner instead of 40,000 | same model | Propane $1.31 an hour ($131.15 a year) — natural gas $0.48 an hour ($48.00 a year). Natural gas wins by $83.15 a year. The $800 install breaks even after 963 cooking hours — about 9.62 years (115.46 months) at 100 hours a year. |
| 60,000 BTU/hr burner instead of 40,000 | same model | Propane $2.62 an hour ($262.30 a year) — natural gas $0.96 an hour ($96.00 a year). Natural gas wins by $166.30 a year. The $800 install breaks even after 482 cooking hours — about 4.81 years (57.73 months) at 100 hours a year. |
| Propane at $3.00 a gallon instead of $4.00 | same model | Propane $1.31 an hour ($131.15 a year) — natural gas $0.64 an hour ($64.00 a year). Natural gas wins by $67.15 a year. The $800 install breaks even after 1192 cooking hours — about 11.91 years (142.97 months) at 100 hours a year. |
| Propane at $5.00 a gallon instead of $4.00 | same model | Propane $2.19 an hour ($218.58 a year) — natural gas $0.64 an hour ($64.00 a year). Natural gas wins by $154.58 a year. The $800 install breaks even after 518 cooking hours — about 5.18 years (62.10 months) at 100 hours a year. |
| Natural gas at $1.20 a therm instead of $1.60 | same model | Propane $1.75 an hour ($174.86 a year) — natural gas $0.48 an hour ($48.00 a year). Natural gas wins by $126.86 a year. The $800 install breaks even after 631 cooking hours — about 6.31 years (75.67 months) at 100 hours a year. |
| Natural gas at $2.00 a therm instead of $1.60 | same model | Propane $1.75 an hour ($174.86 a year) — natural gas $0.80 an hour ($80.00 a year). Natural gas wins by $94.86 a year. The $800 install breaks even after 844 cooking hours — about 8.43 years (101.20 months) at 100 hours a year. |
| $1,500 install instead of $800 | same model | Propane $1.75 an hour ($174.86 a year) — natural gas $0.64 an hour ($64.00 a year). Natural gas wins by $110.86 a year. The $1,500 install breaks even after 1354 cooking hours — about 13.53 years (162.36 months) at 100 hours a year. |
| 200 cooking hours a year instead of 100 | same model | Propane $1.75 an hour ($349.73 a year) — natural gas $0.64 an hour ($128.00 a year). Natural gas wins by $221.73 a year. The $800 install breaks even after 722 cooking hours — about 3.61 years (43.30 months) at 200 hours a year. |
| 0 BTU/hr burner | same model | Propane $0.00 an hour ($0.00 a year) — natural gas $0.00 an hour ($0.00 a year). An exact tie — both fuels cost the same a year. Break-even does not apply — neither fuel costs anything at 0 BTU/hr. |
| $0 install — gas line already in | same model | Propane $1.75 an hour ($174.86 a year) — natural gas $0.64 an hour ($64.00 a year). Natural gas wins by $110.86 a year. The install is $0, so natural gas wins from the first cooking hour. |
| 0 cooking hours a year | same model | Propane $1.75 an hour ($0.00 a year) — natural gas $0.64 an hour ($0.00 a year). An exact tie — both fuels cost the same a year. The install breaks even after 722 cooking hours — but at 0 hours a year, that never arrives. |
| 50 cooking hours a year | same model | Propane $1.75 an hour ($87.43 a year) — natural gas $0.64 an hour ($32.00 a year). Natural gas wins by $55.43 a year. The $800 install breaks even after 722 cooking hours — about 14.43 years (173.19 months) at 50 hours a year. |
Figures are the model's own totals on the numbers you type, computed from unrounded values: the cost per hour is the burner size times the fuel price divided by the energy per unit, the annual cost is the hourly cost times the hours a year, and the break-even is the install divided by the saving per hour, rounded up to whole hours. The displayed figures are rounded to 2dp. The propane tie price is exact to 3dp; the natural gas tie price is rounded to 4dp, so at $4.3716 a therm the two fuels sit $0.00 apart over a year — the exact tie is $4.371585 a therm. The break-even is the smallest whole number of cooking hours whose saving reaches the install. The model assumes the same grill and burner on both fuels and does not count a monthly gas service charge, tank rental, delivery fees, or the grill itself. Prices are illustrative October 2026 levels, cited on the page — check your own bill before you decide. This page is a calculation tool, not financial advice.
At 40,000 BTU/hr, propane at $4.00 a gallon costs $1.75 an hour ($174.86 a year) and natural gas at $1.60 a therm costs $0.64 an hour ($64.00 a year) — natural gas wins by $110.86 a year, and the $800 install breaks even after 722 cooking hours. Prices: EIA residential propane $2.689/gal (week ending Oct 19, 2026); EIA natural gas $13.44/Mcf (2026-27 Winter Fuels Outlook). Source: Bright Side Kit, brightoolbox.com.
$1.75 an hour at the defaults — a 40,000 BTU/hr burner at $4.00 a gallon. A 30,000 BTU/hr burner costs $1.31 an hour and a 60,000 BTU/hr burner costs $2.62.
$0.64 an hour — the same 40,000 BTU/hr at $1.60 a therm. Natural gas is cheaper per BTU: $16.00 per million BTU against $43.72 for propane.
Natural gas, by $110.86 a year at 100 cooking hours — $64.00 against $174.86. Natural gas wins on fuel at every burner size here; only the install can change the answer.
722 cooking hours — about 7.2 years at 100 hours a year, or 3.6 years at 200 hours. At a $1,500 install the break-even is 1,354 hours.
$1.464 a gallon at $1.60 a therm — below the $2.69 EIA bulk average, so propane rarely ties on price alone.
About $4.37 a therm at $4.00 a gallon — far above the $1.30 to $1.65 residential range, so the tie is theoretical.
Yes, from the first hour: a $0 install means no break-even to wait for, and natural gas wins by $110.86 a year.
About 4.7 gallons — at $4.00 a gallon that is about $18.80 a tank, and about 11 hours of cooking at 40,000 BTU/hr.