Router keeps restarting by itself: causes and fixes

A router that keeps restarting by itself usually comes down to unstable power, overheating, bad firmware, or a router that’s starting to fail. Check the power source and airflow first, because those are the easiest things to rule out and the least likely to cause damage. If those don’t help, move on to firmware, then a factory reset, and only then consider replacement or an ISP problem.

What the restarting usually means

Random restarts usually mean the router is losing stable power, getting too hot, running into a firmware problem, or failing at the hardware level. That’s different from a simple Wi‑Fi drop, where the router stays on but devices lose the signal.

If the lights go out and come back, or the router behaves like it has just been unplugged, think power or hardware first. If the restarts happen after heavy use, such as several people streaming or gaming at once, heat or a weak power adapter moves higher on the list. If the problem started after an update or a settings change, firmware or configuration is more likely.

If the router reboots at the same time every day, check for a scheduled reboot, automatic maintenance window, or parental-control timer before you do anything else. A timer can look exactly like a hardware fault.

When this applies and when it doesn’t

This troubleshooting applies when the whole router reboots, not just one phone, laptop, or TV losing connection. A single device dropping off the network can be a device problem, not a router problem.

A useful check is to watch what happens during the restart. If both Wi‑Fi and wired devices lose connection at the same time, the router itself is usually rebooting. If the router stays powered but only internet access disappears, the modem, the ISP line, or a separate setting is more likely.

Do not replace hardware until you’ve checked the basics in order: power, heat, firmware, then reset. If you skip straight to buying a new router, you can miss a bad outlet, a failing adapter, or a modem issue that would have been easier to fix.

Check the power supply and outlet first

Start with the power path, because a weak or loose connection can cause exactly this symptom. Make sure the adapter is firmly seated in the router and at the wall, then try a different outlet if you can.

If the router is plugged into a power strip, try the wall outlet directly for a short test. A failing strip or loose switch can cause brief interruptions that are hard to notice.

Look at the power brick itself. If it feels unusually hot, looks damaged, or seems much lighter than you’d expect for the router model, that doesn’t prove anything by itself, but it does raise suspicion about the adapter. The safer next step is to test with the correct replacement adapter for that exact router model, or to use another known-good adapter only if its voltage, polarity, and current rating match the router’s requirements exactly.

If the router stops rebooting after a different outlet or adapter is used, you’ve likely found the problem. If nothing changes, move on instead of buying random cables or guessing at the power spec.

Cool the router down and improve airflow

Overheating is a common reason for repeated restarts. Many routers sit on a shelf, in a cabinet, or under another device, and they get hot enough to reset when air can’t move around them.

Check for heat with a simple observation: is the case very warm, are the vents blocked, or does the router restart more often after long use? If yes, give it more open space. Place it upright if the design allows that, keep it away from direct sunlight, and don’t stack it under a modem, console, or other warm device.

Dust can also trap heat. A light cleaning around the vents and the surrounding area can help, as long as you do not open the router or spray anything into it. If the router is in an enclosed cabinet, try moving it to an open shelf for a day and see whether the restarts stop.

If better airflow helps, overheating was likely part of the problem. If the router still restarts even in a cool, open spot, the cause may be firmware, power, or failing hardware.

Update firmware and reboot cleanly

If power and heat checks don’t solve it, firmware is the next safe place to look. A buggy update or corrupted settings can make a router unstable, but you should use the exact model’s instructions from its admin page or manual, because update steps vary.

First, save any settings you may need later, such as Wi‑Fi name, password, and ISP details, if your model lets you export them. Then update the router only through the normal manufacturer path. Don’t pull the power during an update unless the router manual tells you to stop and recover another way; interrupting firmware can make the problem worse.

After the update, do a clean reboot: let the router shut down normally if it has a software restart option, or power it off, wait a short moment, then power it back on. This can clear temporary faults without wiping the configuration.

If the router becomes stable after the update or clean power cycle, the issue was probably software-related. If it keeps restarting, don’t keep repeating the same update; move to the next step.

Reset only if the other fixes fail

A factory reset is a last-resort test, not the first move. It erases the saved settings on the router, which usually means Wi‑Fi name, Wi‑Fi password, custom network settings, port forwards, and any other changes you made.

Use the reset only when power, cooling, and firmware checks haven’t helped, and only if you’re ready to set the router up again from scratch. The exact reset method matters because some routers use a pinhole button, some use a menu option, and some require a longer press than others. Follow the model-specific instructions exactly.

After the reset, set up only the basic connection and leave extra rules, timers, and custom settings out for now. If the router still restarts on a plain setup, the problem is less likely to be a bad configuration and more likely to be the power adapter, the router hardware, or a line issue upstream.

How to tell whether it’s actually fixed

The best sign is uptime. Leave the router running for a full day if you can, and check that it stays on without dropping power or rebooting.

Also test during the kind of use that used to trigger the issue. For example, if the router used to restart during evening streaming, use it the same way and watch the lights and connection status. A router that only survives when idle isn’t really fixed.

If your router’s admin page shows uptime, check that it keeps increasing instead of resetting back to a low number. If you don’t have an uptime display, use the fact that all devices stay connected and the lights remain steady as your practical check.

When to replace the router or call your ISP

If the router still restarts after checking power, cooling, firmware, and a factory reset, the odds shift toward a failing router or a bad power adapter. If you’ve already ruled out the outlet and adapter, replacement is usually the next practical step.

If the router seems stable on its own but restarts or loses the internet only when the modem connection is active, call your ISP. The line, modem, or service itself may be dropping and causing the router to react. If the modem has its own error lights or restarts too, that’s a strong hint the issue is outside the router.

Replace the router sooner if the restarts are getting more frequent, happen even in a cool open spot, and continue after a reset. That pattern usually means the hardware is no longer dependable.