@TTC depends on what "wifi guarantee" you think you have. Every Sky customer gets a "wall-to-wall" WiFi guarantee which needs reading carefully https://www.sky.com/help/articles/wall-to-wall-wifi-guarantee. In essence its a way to sell add on packages.
Sky offer 2 separate add-ons which can provide additional kit if WiFi speeds in every room does not meet the guaranteed speed. These are the older. Braodband Boost bundle where the figure is a pretty uselss 3Mb/s and the newer WiFi Max bundle (https://www.sky.com/help/articles/sky-wifi-max) which offers a guarantee of 10Mb/s rising to 25Mb/s if you buy a service offering 125Mb/s or faster.
The other option is to buy and use your own wifi set up which I and many other Sky broadband customers do.
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65inch Sky Glass, 3 Sky Streaming Pucks, Sky Ultrafast + and Sky SR213(white Wifi Max hub) main Wifi from 3 TP-Link Deco M4 units in access point mode
