
These are both methods of increasing your wifi coverage, but they work differently

Wifi Extenders
These work by picking up the wifi signal that is being transmitted by your router and re-transmitting it. So, for instance, if your router is in a hallway, the extender might be placed at the top of the stairs. This could improve wifi reception in rooms at the same level as the extender and above it. They generally come in the form of a special large plug that connects to any mains socket. They may or may not have a “pass-through socket” that means that the quantity of available sockets is not reduced by their use.
Pros of Wifi Extenders
- Do not rely on the quality or configuration of the mains electricity supply.
- No trailing cables (unless the extender’s power supply is via a cable and plug, rather than just a single unit that plugs into a wall socket).
Cons of Wifi Extenders
- Can be fiddly to site the extender in a convenient place (not halfway up the stairs!) where it can simultaneously pick up an adequate signal from the router and transmit that signal onwards to the desired destination. In my experience, “fiddly” is probably a bit of an understatement.

Powerline adaptors
These work by connecting a special mains plug to your router (by means of an ethernet cable). Elsewhere in the property, a similarly special mains plug picks up the internet data transmitted along your internal electricity wiring and transmits it by wifi or ethernet cable (or both, all depending on the model) from the location of the second plug. Some powerline adaptors come with “pass through sockets” so your quantity of available electricity sockets is not reduced by their use.
- In my experience, when powerine adaptors work, they do so more reliably than extenders.
- The only visible cabling is from router to wall socket and, if ethernet is required at the remote end, an ethernet cable from wall socket to computer.
Cons of powerline adaptors
- The electricity sockets where the adaptors are plugged in both/all have to be on the same electricity ring. This might sound obvious and a “non-issue”, but I have encountered several situations in London where a property has been divided into flats (with separate electricity supplies) and then re-joined into one residence. Powerline adaptors may not work in these situations. I have also seen – more than once – brand spanking new kitchens built into newly dug out basements and connected to the electricity mains on a different circuit to the rest of the property. Most people, when asked, don’t know if their property is in such a situation, so I have taken to trying out powerline adaptors with a “suck it and see” attitude and going over to extenders if powerline adaptors don’t work.
Costs
You can buy either solution for about £50.
Alternatives

There is another, newer, solution called a “mesh” setup in which a router and several wifi “satellites” (bought together as a single product) automatically set themselves up to spread wifi around the property. I don’t have any experience of these, but they do have a good reputation. Think in terms of £150-£300.
Both extenders and powerline adaptors are apt to lose the connection from time to time. Probably the best way to get an internet connection from A to B is via an ethernet cable. This is the most robust method and will result in the fastest transmission speeds – but who wants yet more unsightly cables for people to trip over? In new properties recently, and also in recently refurbished ones, it is quite common to embed ethernet cables in the walls, with standard ethernet sockets at either end. Then, it is just a matter of connecting an ethernet cable from the router to a socket at one end and another ethernet cable at the other. Another router could be attached to this cable so as to provide wifi at the remote location.
A word of caution if buying extenders or powerline adaptors: I have seen the packaging of some powerline adaptors include the word “extender”. This is misleading. If you are looking for an extender then make sure there is no mention of “powerline adaptor” anywhere in the blurb or packaging. If you are looking for powerline adaptors then make sure that that wording is present.
The illustrations are all taken from Amazon. I’ve not added links as they change so frequently. Just go to Amazon and use their search box to search for “mesh wifi”, “wifi extenders”, or “powerline adaptors”
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