Can I enter monthly therms instead of daily?

Yes. Divide by days to get daily usage, or set daily = monthly/30 and adjust billing days.

Tiered or time-of-use rates?

Not included. Use a blended rate if you have tiers.

Are delivery charges included?

Enter fixed fees for delivery/base charges. Some utilities itemize them separately.

Commercial demand charges?

Not included; this is aimed at residential-style flat therm rates.

This uses one percentage; your bill may have multiple surcharges. Add them into the tax% for simplicity.

finance calculator

Natural Gas Cost Calculator

Estimate your natural gas bill using daily therms, rate per therm, billing days, fixed fees, and taxes.

Results

Monthly therms: 180.00
Energy cost: $216
Fixed fees: $15
Taxes/fees amount: $0
Estimated total bill: $231

How to use this calculator

Enter average daily therms.
Enter your rate per therm and billing days.
Add fixed monthly fees and optional tax/fee percentage.
See monthly therms, energy cost, fees, taxes, and total bill.

Inputs explained

Average daily therms: Daily natural gas usage; divide last bill’s therms by billing days if needed.
Rate per therm: Your energy charge per therm (from your plan/bill).
Billing days: Number of days in the billing cycle.
Fixed monthly fees: Base/customer charges not tied to usage.
Taxes/fees (%): Optional percent applied to subtotal; set to 0 if unknown.

How it works

Energy cost = daily therms × rate × billing days.

Subtotal = energy cost + fixed monthly fees; taxes/fees apply to the subtotal.

Formula

Monthly therms = Daily therms × Billing days
Energy cost = Monthly therms × Rate
Subtotal = Energy cost + Fixed fees
Tax/fees = Subtotal × Tax%
Total bill = Subtotal + Tax/fees

When to use it

Estimating this month’s gas bill from your typical daily therms.
Comparing supplier plans by plugging in different rates and fees.
Budgeting for high-usage months by increasing daily therms or days.

Tips & cautions

If you only know monthly therms, divide by days for daily usage, then multiply back—same math.
Set taxes to 0 if you’re unsure; add later when you see your bill.
Fixed fees matter—include them to avoid underestimating the total.
Assumes flat therm rate; no tiered or time-of-use pricing.
Ignores demand charges (uncommon for residential gas).
Taxes/fees simplified as one percentage; actual bills may itemize surcharges.

Worked examples

6 therms/day, $1.20/therm, 30 days, $15 fixed, 0% tax

Monthly therms = 180
Energy cost ≈ $216
Subtotal ≈ $231
Total ≈ $231

8 therms/day, $1.05/therm, 31 days, $20 fixed, 5% tax

Monthly therms = 248
Energy cost ≈ $260.40
Subtotal ≈ $280.40
Tax ≈ $14.02
Total ≈ $294.42

Deep dive

This natural gas cost calculator multiplies your daily therms by rate and billing days, then adds fixed monthly fees and optional taxes to estimate your total bill.

Use it to compare plans or budget for seasonal usage spikes with a quick, flat-rate estimate.

FAQs

Can I enter monthly therms instead of daily?: Yes. Divide by days to get daily usage, or set daily = monthly/30 and adjust billing days.
Tiered or time-of-use rates?: Not included. Use a blended rate if you have tiers.
Are delivery charges included?: Enter fixed fees for delivery/base charges. Some utilities itemize them separately.
Commercial demand charges?: Not included; this is aimed at residential-style flat therm rates.
How do taxes vary?: This uses one percentage; your bill may have multiple surcharges. Add them into the tax% for simplicity.

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Estimates only. Actual bills may include tiered rates, surcharges, or other fees. Check your utility bill for exact terms.