What Is a Static IP Address — and Do You Actually Need One?

A static IP address is one that does not change. That sounds simple, but the phrase is used for two different things: the public address your internet provider gives your home, and the private addresses your router gives your devices. Most people who search for a static IP need the second kind, which is free and takes two minutes to set up. The first kind costs money and is only needed for a few specific jobs.

Two Different Things Called “Static IP”

How Addresses Are Normally Assigned

Both kinds of addresses are normally handed out automatically by DHCP, a protocol that leases an address to a device for a period of time. Your provider leases a public address to your router; your router leases private addresses to your phones, laptops and TVs. When a lease expires or a device reconnects, it may get a different address. That is a dynamic address.

For everyday browsing and streaming, dynamic addresses are perfect: nothing needs configuring, and conflicts are avoided automatically. They only become a problem when something needs to find a device at a known address.

A Static Public IP From Your Provider

Your public address is the one the internet sees; you can check it on What Is My IP?. With most home plans it is dynamic, although in practice many providers keep the same address for weeks or months.

You need a static public IP when other people or services must reach your home at a fixed address:

• Hosting a website, game server or mail server at home.
• Remote access to a home network or office through a VPN server you run yourself.
• Business tools that only accept connections from an allowed address.

Static public addresses are usually part of business plans or a paid add-on. Before paying, consider the alternatives: a dynamic DNS service gives your changing address a fixed name, and tunnel services make remote access work without any public address at all. If your router does not even get a public address, because the provider uses carrier-grade NAT, see what is CGNAT; a static IP from the provider is then the main way to make hosting work.

A Fixed Local IP in Your Home Network

Inside your home, a fixed address is needed whenever a setting points to a device by its address:

• Port forwarding sends incoming connections to one device; if its address changes, the rule points to nothing. See how to port forward.
• Game consoles with manually forwarded ports need a stable address to keep an open NAT; see NAT type strict.
• Printers, NAS drives, cameras and smart-home hubs are easier to reach when they always have the same address.
• Parental controls and access rules on older routers that identify devices by IP address.

How to Set Up a DHCP Reservation

The best way to fix a local address is a DHCP reservation: the router keeps handing out addresses automatically but always gives the same one to a particular device, identified by its MAC address. Nothing changes on the device itself.

1. Log in to the router; if you need its address, see what is my router IP.
2. Open the list of connected devices or DHCP clients and find the device. The MAC address lookup helps identify entries with unclear names.
3. Look for Address Reservation, DHCP Reservation, Static Lease or IP & MAC Binding, usually under LAN, DHCP Server or Network settings.
4. Reserve the device’s current address, or choose another free address in your network, and save.
5. Restart the device or reconnect it so it picks up the reserved address.

Phones and laptops with a private, randomized Wi-Fi address may show up with a new MAC address on each network or after a reset. For a device that needs a reservation, turn off the private address for your home network, or reserve the address again if it changes.

Setting a Static IP on the Device Instead

You can also type a fixed address directly into a device’s network settings. On Windows, it is under Settings → Network & internet → Wi-Fi or Ethernet → Hardware properties → IP assignment → Edit → Manual; on a Mac, under System Settings → Network → your connection → Details → TCP/IP → Configure IPv4 → Manually.

This works, but it is easier to get wrong. You have to enter the subnet mask, the gateway (your router’s address) and DNS servers yourself, and you must pick an address outside the range your router hands out automatically; otherwise two devices may end up with the same address and both lose their connection. Use a reservation in the router whenever you can, and manual settings only for devices that do not work with DHCP.