One of the larger railway station branches of Simply Food, located on the west side of the station (ie the Grosvenor hotel side). It’s an odd 'L’ shape, and takes a little while to find your way to the relevant section, but they have a reasonably good selection of sandwiches and snacks to stock up with before a journey, or ready meals if you are on your way home and fancy something easy.

They have a small fresh bread and fresh fruit and veg section, as well as a surprisingly good wine section. I bought my wine here for a leaving do from work, and got a good deal on two dozen bottles.

It get a bit crowded at rush hours, but there are checkouts on both sides (there are actually three entrances and exits) so the queues aren’t too bad.

(PS - it’s not actually within W H Smith - the photo is of the separate store).