The Area Codes of United Kingdom: City/Town or RegionArea code 1.Dalmally01838 (+441838) 2.Darlington01325 (+441325) 3.Dartford01322 (+441322) 4.Daventry01327 (+441327) 5.Derby01332 (+441332) 6.Dereham01362 (+441362) 7.Devizes01380 (+441380) 8.Dingwall01349 (+441349) 9.Diss01379 (+441379) 10.Doncaster01302 (+441302) 11.Dorchester01305 (+441305) 12.Dorking01306 (+441306) 13.Dover01304 (+441304) 14.Downham Market01366 (+441366) 15.Downpatrick (Northern Ireland)02844 (+442844) 16.Driffield01377 (+441377) 17.Dudley01384 (+441384) 18.Dulverton01398 (+441398) 19.Dumbarton01389 (+441389) 20.Dumfries01387 (+441387) 21.Dunbar01368 (+441368) 22.Dundee01382 (+441382) 23.Dunfermline01383 (+441383) 24.Dungannon (Northern Ireland)02887 (+442887) 25.Dunkeld01350 (+441350) 26.Dunoon01369 (+441369) 27.Duns01361 (+441361) 28.Dursley01453 (+441453)