Years ago, you almost had to be a networking guru to make anything work on your home network. These days port forwarding is rarely talked about because it's almost never needed. And that's because online servers work as middle men to connect your phone to your smart home gadgets and game servers allow players to connect to their friends, sometimes even between different games consoles. It all happens transparently in the background. 

But sometimes you'll have a problem that can only be fixed by forwarding ports. Sometimes you will see a NAT error, or a message that says your NAT type is wrong and needs to be changed. Here we'll explain what that means and how to do it.

What are ports?

Your broadband router is something you install and then forget about, but it's one of the most important devices you own. It sits between your phone, laptop, Xbox, PS4, TV and other devices and connects them and the internet. It's a little like a postal system, ensuring that data coming in and going out is directed to the appropriate device.

Ports are a bit like numbered doors - they can be open or shut to data. Most data uses a few universally agreed open doors (port 80, for example), but certain games, apps or devices are awkward and need to use other ports which are closed by default. That's bad design for the most part, but if you have a game or use a service which won't work properly online, here's how to forward ports and get it working.

How to set up port forwarding

First, you'll need to figure out which ports you need to open. If you don't know, take a look at this Port Forward list which includes a lot of popular games and apps. Some common ports are 25565 (Minecraft), 6881–6887 (BitTorrent clients), and 3724 (World of Warcraft). Once you have this information, follow these steps:

1. In a web browser, type your router's IP address number into the address bar, and press Enter. If this makes no sense, then here's how to connect to your router.

2. Enter your username and / or password when prompted. On some routers you'll only be asked for this when you try to change advanced settings. The default username and password should be in the manual, on a sticker on router itself, or written down somewhere if you changed them from their defaults.

You can use Google to find the defaults for most routers. If you don’t remember what you changed them to, or can't find the defaults, you’ll need to reset your router which is typically done using the pin-hole reset button.

3. Router interfaces vary a lot, but you need to look for a tab or menu called applications, port forwarding, port triggering, NAT, advanced or something similar.

4. Regardless of your router make and model, you’ll need to enter the same basic information to forward ports. Some routers might offer a list of games and apps which makes things very easy, but if your game or app isn't there, create a new entry (name it) and enter the port number you want to open, or enter a range of ports to open.

How to port forward: open ports on a router

For example, if a game needs port 25, 443 and 3478-3480 to be open you'll need to create three entries, one for 25, one for 443 and a third for the rage 3478-3480.

5. Choose the protocol for these ports (TCP, UDP, or both). Again, search online if you don't know which to choose. Typically, you'll need some TCP ports and some UDP ports. There may be some overlap.

 How to port forward: open ports on a router

6. Now choose which device on the network the rule should apply to. Your router might let you choose a friendly name from a list, or you may have to do it by IP address. Regardless of the method, you will probably need to assign a static IP address to that computer, console or other device.

A static IP address means telling your router to always give the same IP address when that device connects to it. By default, routers use a DHCP server to assign addresses at random, so your Xbox's IP address might change next time you turn it on. That's no good if you need to open ports, but a static IP address means the port forward rule will always work.

How to set a static IP address

As with port forwarding, you'll have to search your router's menus to find static IP settings, but Google is again your friend if you don't have a manual for your router.

Sometimes it's possible (and easier) to set a static IP address on the device itself rather than the router. If you can find a setting in its menus to assign an IP address, make sure you use the same first three numbers of your router's IP address (such as 192.168.0). The final number must be unique on your network, and that's why it's best to assign a static address on your router rather than the device itself so the router doesn't give the same address to another device on the network. 

Make sure you save any changes you make before going to a different page on your router's interface or on your PC or games console. You can then check that the static IP address is working properly by looking in the network menu of your device to see its current IP address.

Finish port forwarding rules

The next step after choosing which device the port forward rules should apply to is to double-check that the rule is enabled. Creating the rule and saving it is one thing, but you must ensure that it's active (or enabled - whatever term your router uses). 

Sometimes there is no option: the rule is active if it's in the list. On other routers you can enable and disable rules without deleting them. Bear in mind that a game, service or gadget may need more than one port open, and this may require creating multiple rules.

Finally, when you've enabled your rule(s) and saved all changes, use this online port forward checker to find out if you have been successful.

Need a router upgrade? Here are the best routers. And if you just want better Wi-Fi, check out these mesh Wi-Fi kits.