Today, EE subscribers can pre-order a 4G variant of the Samsung Galaxy Watch. Currently, this is the only carrier that will stock the cellular version of the Galaxy Watch in the United Kingdom. Customers can pre-order online, over the phone, or in-store. You can sign up for a payment plan to get the Watch for GBP 20/month for 24 months. Signing up for the connected Galaxy Watch comes with unlimited data on the Watch and an extra 1GB data boost for the companion smartphone line. The dedicated line on the Galaxy Watch will let you make calls, send and receive SMS messages, and stream music...
Source: https://www.gsmarena.com/samsung_galaxy_watch_4g_can_now_be_preordered_in_the_uk-news-34044.php