Should you repair or replace your microwave?
Updated August 2026
← Every repair-or-replace call
Replace a countertop microwave instead of repairing it, and repair an over-the-range or built-in unit only while it is under about 5 years old. A countertop model costs $80–200 new, and a single service call is $90–150 before any part goes in, so the repair loses on arithmetic every time. Built-in and over-the-range units are different money at $300–700 installed, with a magnetron at $100–250 and a door interlock switch for less. One rule holds regardless of price: do not open the cabinet yourself, because the high-voltage capacitor stores a charge that can kill after the cord is unplugged.
The short version
The 50% rule collapses on countertop microwaves, because the replacement price is so low that almost any diagnosis plus labor exceeds half of it. That is why most appliance shops stopped repairing them. Over-the-range units flip the logic. They cost $300–700 installed, they are bolted to cabinets and connected to a duct, and swapping one takes a two-person lift, so a $150–250 magnetron or a $75–150 door switch on a 3-year-old unit is genuinely worth doing. Past 7 years, an over-the-range microwave with a dead magnetron or a failed control board has reached the end of its 7 to 10 year run, and the money belongs in a new one.
Your situation, decided
| Situation | Verdict | Why |
|---|---|---|
| Countertop unit of any age, any fault | Replace | A $90–150 service call alone rivals the $80–200 price of a new one |
| Over-the-range unit under 5 years, magnetron dead | Repair | A $100–250 part on a $300–700 installed appliance |
| Door switch or interlock failed, built-in under 7 years | Repair | A $75–150 part, and the unit is nowhere near end of life |
| Control board out on an over-the-range unit past 7 years | Replace | Board plus labor approaches a new unit at end of service life |
| Sparking inside, waveguide cover burnt | Repair | A $10–20 mica cover; change it before using the microwave again |
What each path costs
Repairs typically run $100–300; a replacement is $300–700 installed. Microwaves last 7–10 years. Countertop units at $80–200 are disposable by design; an over-the-range unit under 5 years earns a magnetron or door switch. Price your own number on the home maintenance cost calculator before you commit either way.
The repair-or-replace call is easy when you know the unit's age and service history. OnOtto keeps both, plus the maintenance that delays this decision for years.
Start your home's service log, freeFrequently asked questions
Is replacing the magnetron in a microwave worth it?
Only in a built-in or over-the-range unit that is still young. The magnetron runs $100–250 installed, which is reasonable against a $300–700 over-the-range appliance under 5 years old and absurd against a $120 countertop model. Magnetrons also tend to fail late in life, so on a 9-year-old unit the repair leaves you a working microwave with a tired door switch and a worn turntable motor. Ask what the diagnostic fee is and whether it applies toward the repair.
Why does my microwave run but not heat the food?
That exact pattern, turntable spinning and light on but nothing getting hot, points at the high-voltage side: the magnetron, the diode, or the capacitor. A blown thermal fuse or a failed door interlock switch can also stop heating while everything else still runs. None of these are homeowner checks. Our guide on a microwave that runs but will not heat covers what a technician tests. Expect $100–300 on a unit worth repairing at all.
Can I safely repair a microwave myself?
No. The high-voltage capacitor inside holds a lethal charge long after you unplug the unit, and discharging it safely takes a specific tool and technique. This is the one kitchen appliance where the standard advice is to keep the cabinet closed and hand it to a technician. Cleaning is a different matter: wiping the interior, washing the grease filter, and swapping the charcoal filter are all safe with the unit unplugged. See how often to change the filters.
How long should an over-the-range microwave last?
Plan on 7 to 10 years, and less if it serves as your only cooking vent. Grease is what shortens it, because a saturated aluminum mesh filter makes the blower labor and lets vapor reach the electronics sitting directly above a hot cooktop. Washing the mesh filter monthly and following the maintenance checklist keeps it near the top of that range. Compare yours against the microwave lifespan guide before spending on any repair.