There are currently two 24 hour off licence in the London Borough of Bexley:
Asda Belvedere, 301 Lower Road, Belvedere, Kent, DA17 6DF - 020 3691 0932 (Not currently open 24 hours)
Sainsbury's Crayford, Stadium Way, Dartford, Kent, DA1 4HW - 01322 529254 (Not currently open 24 hours)
There are only two 24 hour off licences in Bexley, which are both large supermarkets. Unfortunately, neither Asda Belvedere nor Sainsbury's Crayford is open 24 hours a day at the current time (even though both premises are licensed to sell alcoholic beverages 24 hours), therefore you can't legally buy alcohol all night from a shop in the London Borough of Bexley. If you're after late night booze, you will need to either travel to a 24hr off licence in a different area or use a All Night Alcohol Delivery Service which delivers beers, wines and other drinks to most of London and parts of Kent throughout the night.
Please Note: Just because a shop is listed as having a 24 hour alcohol licence doesn't necessarily mean that the shop is open 24 hours a day, 7 days a week. It's up to each individual shop to decide whether or not it uses its 24 hour alcohol licence (there are some shops that have decided not to sell booze all night even though they are licensed to sell alcohol 24 hours). It's also worth noting that large 24 hour supermarkets (Tesco, Sainsbury's and Asda) are not open all night on Saturday, Sunday and bank holidays (due to Sunday trading laws in England and Wales), so are only of any use on weekdays or Friday nights. Some large Tesco supermarkets (usually Tesco Extra branches) now open at midnight on Monday morning (probably classed as Sunday night by most people). We've tried to list the phone number for each 24 hour off licence so you can confirm opening times before setting off on your quest for 24 hour booze. If you're planning to visit one of the large supermarket chains then you may prefer to use their store locator to check opening times.