A little while ago I noticed this Sparrow. At first glance I crossed it off in my mind as Tree Sparrow (Passer montanus) another time I saw it I noticed the black bib -Male House Sparrow (P domesticus). Clickychick saw it and said "is that a Tree Sparrow or a House Sparrow" so I looked and didn't know!
Brown crown white collar and dark cheek patch - Tree Sparrow. Hang on that bib should be on a male House Sparrow and now I look more closely the cheek patch is a smudge not a nice clear dark mark. All I can make it into is a hybrid, I have taken some advice from various quarters. We have ruled out Italian Sparrow, thank goodness, I didn't want an invasion of twitchers.
Watching it more closely I think it is paired with a female House Sparrow which sorts out its sex. Tree Sparrows look the same no matter the sex. I also think it may be breeding in a neighbours nest box so it will be interesting to see what comes along as the seasons unfold.