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Appliance lifespan

Furnace Lifespan Calculator: How Long Does a Furnace Last?

Enter the year yours was installed to see how much life is left in your gas furnace and when to start budgeting for a replacement. Free, no signup.

Your gas furnace

Expected life for a gas furnace: about 15 to 20 years.

Life remaining

- years left
Enter the year it was installed to see where it stands.
Current age -
Expected life 15 to 20 yrs
Life used -

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How long does a gas furnace last?

A gas furnace typically lasts 15 to 20 years. Enter the install year and this calculator estimates how much service life is left and when to start planning for a new one, so a mid-winter breakdown does not force a rushed decision.

Changing the filter regularly and getting a yearly tune-up help a furnace reach the top of its range. As it ages, watch efficiency and your gas bill: a new high-efficiency unit can pay back part of its cost in lower heating bills.

These lifespans are typical ranges for a well-maintained unit. Hard water, heavy use, and skipped maintenance shorten them; regular service extends them. Use the estimate to plan a replacement fund, not as a firm expiration date.

Frequently asked questions

How long does a gas furnace last?
A well-maintained gas furnace lasts about 15 to 20 years. Regular filter changes and annual tune-ups help it reach the high end; neglected furnaces tend to fail earlier.
When should I replace my furnace?
Start budgeting once it passes about 15 years, especially if repairs are getting frequent or your heating bills are climbing. Replacing before a failure lets you shop deals instead of paying emergency rates in a cold snap.

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