How long does a microwave last?
Updated August 2026
A microwave lasts 7–10 years, and the mount matters: over-the-range and built-in units, which cost more and get pampered, tend toward the 10-year end, while a countertop model that runs hard every day often taps out closer to 7. The part that ultimately quits is usually the magnetron, the vacuum tube that generates the microwaves, though a worn door interlock switch or a fried control panel can end things sooner. Total cooking hours, not calendar years, is what really wears one out.
Lifespan by type and situation
| Type or situation | Typical lifespan | Why |
|---|---|---|
| Countertop, heavy daily use | 6–8 years | The most-used, least-expensive category |
| Countertop, light use | 8–10 years | Fewer cooking hours stretch the magnetron |
| Over-the-range | 9–11 years | Costs more and gets treated more gently |
| Built-in or drawer | 9–12 years | Premium components, but pricey to replace |
| Grease-clogged vent filters | Low end | Trapped heat stresses electronics on OTR units |
| Door slammed or run empty | Cut 1–3 years | Wears interlock switches and can damage the magnetron |
Signs yours is near the end
- Food that comes out lukewarm no matter the power level or time, the classic dying-magnetron symptom
- Buzzing, humming, or arcing and sparks inside the cavity during cooking
- A burning or electrical smell, or a turntable and cavity that stay cool while it runs
- A door that must be pressed or held to start, a sign the interlock switches are wearing out
- A control panel with dead pads, a dim display, or buttons that no longer respond
How to add years
A microwave asks little, but a few things add years. Never run it empty, since with no food to absorb the energy the magnetron cooks itself. Keep the interior clean so splatter does not char and arc, and close the door gently rather than slamming it, which spares the interlock switches that are a common failure point. On an over-the-range unit, changing the grease and charcoal filters keeps airflow up so trapped heat does not bake the electronics; the over-the-range microwave checklist has the schedule. When it stops heating, the magnetron is usually the cause, and on a unit past 7 or 8 a $100–200 repair rarely beats replacing it for $100–500. Our guides on a microwave that will not heat and sparking inside help you tell a cheap fix from a lost cause.
What it costs to replace: plan on $100–500 ($400–1,000 for built-in and drawer models plus install). Replacing on your own schedule, before it fails, is almost always cheaper than the emergency version. The home maintenance cost calculator helps you set the money aside before it comes due.
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Track your home's systems, free for 30 daysFrequently asked questions
Is it worth fixing a microwave that will not heat?
Rarely, on a countertop unit. A magnetron replacement runs $100–200 with labor, and a basic countertop microwave costs $100–200 new, so you would spend the price of a replacement to repair an aging one. The math flips for built-in, drawer, and over-the-range models that cost $400 to well over $1,000 installed; there, a magnetron or door-switch repair is often worth it. Never open the cabinet yourself, though. The high-voltage capacitor can hold a lethal charge even unplugged.
Why does my microwave spark inside?
Usually metal or burnt food debris. Anything metallic, foil, a fork, or metal trim on a dish, reflects the microwaves and arcs; so does baked-on grease or a scorched spot on the cavity wall. The most common fixable cause is a worn or charred waveguide cover, the small mica panel on the interior wall, which is a cheap part to swap. If it still sparks with a clean, metal-free cavity and an intact cover, the magnetron may be failing. See our guide on sparking inside a microwave for the full checklist.
Do over-the-range microwaves last longer than countertop ones?
Somewhat, mostly because they cost more and run less. Over-the-range units average 9–11 years versus about 7 for a hard-used countertop model, thanks to sturdier components and gentler duty. Their catch is the vent: grease-clogged filters trap heat that cooks the control board, so they punish neglect. Change the grease and charcoal filters on schedule and an over-the-range microwave will comfortably reach a decade. Ignore them and it can fail as fast as any cheap countertop unit.
How can I make a microwave last longer?
Four habits do most of the work. Never run it empty, because the magnetron needs food to absorb its energy. Wipe up splatter so it cannot char and arc against the walls. Close the door gently to protect the interlock switches. And on an over-the-range model, keep the vent filters clean so heat escapes instead of baking the electronics. None of it takes more than a few minutes a month, and together they push a microwave toward the 10-year end of its 7-to-10-year range.