Your IP address changes automatically when you restart your modem or router, switch networks, or your internet provider assigns you a new one—usually without you doing anything

Your IP address is a number your internet provider assigns to identify your device on the internet, like a mailing address for data. Most home internet users have a dynamic IP address, which means it can change. Your provider doesn't change it to bother you—they change it because they have thousands of customers and a limited pool of addresses to hand out. When you're not using the internet, your address goes back into the pool for someone else.

The most common reason your IP address changes is that you restarted your modem or router. When the modem powers back on, it contacts your internet provider and asks for an address. The provider usually gives you the same one you had before, but not always—especially if you've been offline for a while. A power outage, unplugging your equipment, or a service interruption all count as a restart.

You can also trigger a change by switching to a different network entirely: moving from home WiFi to a coffee shop, or from your home network to a mobile hotspot. Each network has its own IP address system, so you get a new address when you join.

Key Takeaways

  • Dynamic IP addresses change automatically when you restart your modem, switch networks, or after a set period of time your provider decides.
  • Restarting your modem is the single most common reason for an IP address change and usually takes a few minutes to complete.
  • You can request a static IP address from your internet provider if you need the same address all the time, though this usually costs extra.
  • Websites and services can still find you after your IP changes because they use cookies, login accounts, and other methods that don't depend on your address.

How often IP addresses change on their own

If you never restart your modem, your IP address may stay the same for weeks or months. However, most internet providers set an expiration date on the address they give you—typically between 24 hours and several months, depending on the provider. When that time runs out, the provider recycles the address and assigns you a new one the next time your modem checks in.

You won't see this happen. Your modem automatically renews its address lease in the background, usually at night or when you're not actively using the internet. If the renewal assigns you a new address, you won't notice unless you were tracking your IP for a specific reason.

Some providers are more aggressive about cycling addresses than others. Comcast, for example, typically renews every 24 hours, while some smaller providers might wait weeks. There's no way to predict exactly when yours will change without contacting your provider directly.

What happens when you restart your modem or router

Restarting your modem is the fastest way to change your IP address on purpose. Unplug the power cable from the back of the modem, wait 30 seconds, and plug it back in. The modem will take 2 to 5 minutes to restart and reconnect to your provider's network. During this time, your internet will be down.

When the modem comes back online, it sends a request to your internet provider asking for an IP address. The provider's system checks whether your old address is still available. If you've only been offline for a few minutes, you'll usually get the same address back. If you've been offline longer, or if your provider's system has already recycled that address to someone else, you'll get a new one.

Restarting your router alone (the device that broadcasts WiFi) will not change your IP address. Your router gets its address from the modem, so you have to restart the modem itself. If you have a combined modem-router unit, unplugging that will restart both at once.

Static IP addresses and why some people need them

If you need your IP address to stay the same, you can request a static IP address from your internet provider. A static address doesn't change unless you manually change it or your service is disconnected for an extended period. Most providers offer this as an add-on service, usually for $10 to $20 per month extra.

Static addresses are useful for specific situations: running a home server, setting up remote access to your computer, or hosting a website from home. Most home users don't need one. Streaming, browsing, email, and video calls all work fine with a dynamic address.

If you think you need a static address, contact your internet provider and ask whether they offer it and what the cost is. Not all providers offer static IPs to residential customers, so check before assuming it's available.

How websites and services track you after your IP changes

When your IP address changes, websites and online services don't lose track of you because they don't rely only on your IP to identify you. They use cookies (small files stored on your device), login accounts, and device fingerprints to remember who you are. Your email stays in your inbox, your social media account stays logged in, and your streaming service remembers what you were watching—all because of these other methods, not your IP address.

The only time your IP address matters for recognition is if a website is actively blocking or allowing traffic based on IP. For example, if you set up two-factor authentication on your bank account, the bank might ask you to verify your identity the first time you log in from a new IP address. This is a security feature, not a sign that you've been locked out.

Checking your current IP address

To see your current IP address, open a web browser and search "what is my IP" or visit a site like whatismyipaddress.com. The site will display your public IP address—the one your internet provider assigned to your modem. This is the address websites see when you visit them.

Your device also has a private IP address that only your home network uses. This is usually something like 192.168.1.100 and is different from your public IP. If you need to find your private IP for troubleshooting or to set up port forwarding, you can find it in your device's network settings, but most people never need to look at it.

Reasons your IP might change unexpectedly

Beyond the normal reasons, your IP can change if there's a service outage in your area. When service is restored, your modem reconnects and may receive a different address. A power outage has the same effect—your modem loses power, restarts when electricity returns, and gets a new address from your provider.

If you've been offline for several days or longer, your provider is more likely to assign you a different address when you reconnect. Providers recycle unused addresses quickly, so a long absence makes a change more probable.

Switching internet providers will definitely change your IP address, since you're now using a different company's network and address pool. This is one of the few changes you can predict in advance.

Frequently Asked Questions

Can I keep my IP address from changing?

You can request a static IP address from your internet provider, which will stay the same unless you disconnect service or manually change it. This usually costs extra per month. For most home users, a dynamic address that changes occasionally causes no problems.

Will my IP address change if I just restart my router?

No. Restarting only the router (the WiFi device) will not change your IP address. You have to restart the modem, which is the device that connects directly to your internet provider's network. If you have a combined modem-router unit, restarting that will change your IP.

Does a VPN change my IP address?

A VPN masks your real IP address and shows websites a different one instead—the VPN server's address. Your actual IP doesn't change, but websites see the VPN's IP instead. When you disconnect from the VPN, websites see your real IP again.

How long does it take for my IP to change after I restart my modem?

The modem itself takes 2 to 5 minutes to restart and reconnect. Your IP address is assigned during this reconnection, so you'll have a new address (or the same one) within that window. You'll know it's done when your internet connection comes back.

Will changing my IP address affect my online accounts?

No. Your email, social media, streaming accounts, and other services use cookies and login information to recognize you, not your IP address. You may see a security prompt asking you to verify your identity the first time you log in from a new IP, but your accounts won't be affected.