How often should you replace a surge protector?
Updated July 2026
Replace a plug-in surge protector every 2 to 3 years, and immediately after any large surge or a nearby lightning strike. The catch is that the protective parts inside, metal-oxide varistors (MOVs), wear down a little with every spike they absorb and then fail silently. A worn strip keeps powering your devices exactly like new, so nothing tells you the protection is gone, until the next surge sails straight through to a $1,000 TV or a full home office of electronics.
What changes the interval
| Your situation | Interval | Why |
|---|---|---|
| Everyday strip, no major surges | Every 2–3 years | MOVs age gradually even without big hits |
| After a lightning strike or big surge | Replace now | One large event can exhaust the MOVs at once |
| Protecting a PC, TV, or AV gear | Every 2 years | Sensitive electronics justify a fresh margin |
| Strip with a "protected" light gone dark | Replace now | A dark indicator means the MOVs are spent |
| Basic power strip (no joule rating) | It is not protection | A relay strip switches power, it does not clamp surges |
The cost of skipping it
What skipping it costs: the whole point of a surge protector is to sacrifice itself so your electronics survive, but once its joules are used up it protects nothing while looking perfectly fine. A single surge can take out a TV ($500–1,500), a gaming PC or home-office setup ($1,000–3,000), or the control boards in smart appliances. Some products carry a connected-equipment warranty, but those require a working, registered unit and rarely pay out easily. A quality replacement strip is $20–40, and a whole-house unit at the panel adds a second layer. Cheap insurance for expensive gear.
How to do it (5 minutes · DIY, unplug and swap)
- Check each strip for a "protected" or "grounded" status light; if it is dark, the surge protection is done even if the outlets still work.
- Note the joule rating when you buy: 600–1,000 joules is fine for lamps, 1,000–2,000+ for computers and home theater.
- Move devices to the new strip and plug it into a grounded, three-prong outlet, never a two-prong adapter.
- Do not daisy-chain strips or run one off an extension cord; that defeats the ground path.
- Date the strip with a marker so you know when the 2–3 year clock started.
- For real protection, pair plug-in strips with a whole-house surge protector at the panel.
Knowing the interval is the easy half. OnOtto reminds you at the right interval, and it won't let you snooze it into next year. Tasks persist until they're done, and completing surge protector replacements schedules the next one automatically.
Put this on autopilot, free for 30 daysFrequently asked questions
How can I tell if my surge protector still works?
Look for the status light: most surge strips have a "protected" or "protection present" LED that stays lit while the MOVs are healthy and goes dark once they are spent. If the light is off but the outlets still power your devices, the protection is gone and the strip is now just a power strip, so replace it. Strips with no indicator light give you no warning at all, which is why you replace those on the 2-to-3-year schedule regardless of appearance.
What is the difference between a power strip and a surge protector?
A power strip just multiplies outlets; it switches power on and off and offers zero surge protection. A surge protector adds MOVs that clamp voltage spikes and is rated in joules (its total absorption capacity) and clamping voltage (how soon it reacts). If the packaging shows no joule rating and no UL 1449 surge listing, it is a power strip, no matter how many outlets it has. For anything with a circuit board, you want that joule rating and listing.
Do I need a whole-house surge protector too?
They complement each other. A panel-mounted whole-house unit clamps the big surges coming in from the grid and protects hardwired items a strip cannot reach: HVAC boards, the furnace, appliances, and lighting. Plug-in strips then handle the smaller surges generated inside the home and add a second stage for sensitive electronics. A whole-house unit runs $200–500 installed and lasts longer, but it does not replace point-of-use strips. See how often to replace the whole-house unit.
Should I replace my surge protector after a power outage?
Not for a routine outage, where the power simply drops and returns; that does not wear the MOVs. Do replace it after events that involve a real spike: a nearby lightning strike, a downed line, a transformer blowing, or a surge big enough to trip protection or fry another device in the house. If any connected gear was damaged, assume the strip took a hard hit and is compromised, and swap it. When unsure, a $20–40 strip is not worth risking your electronics on.