| Code | Name | Region |
|---|---|---|
| GBYXA | Yoxall | STS |
| GBYMH | Ystrad Mynach | CAY |
| GBYST | Ystradgynlais | POW |
| GBYSD | Ystradowen | VGL |
| GBZLS | Zeals | WIL |
| GBZLH | Zelah | CON |
| GBYRM | Yarm | STT |
| GBYMO | Yarmouth | IOW |
| GBZDO | Yarnton | OXF |
| GBYAT | Yate | GLS |
| GBYTE | Yateley | HAM |
| GBYTN | Yatton | NSM |
| GBZDP | Yaxley | CAM |
| GBYDG | Yeading | HIL |
| GBYDN | Yeadon | LDS |
| GBYFR | Yell And Fetlar | ZET |
| GBYLL | Yelland | |
| GBYVT | Yelvertoft | NTH |
| GBYLT | Yelverton | DEV |
| GBYEO | Yeovil | SOM |
| GBYMA | Yeovil Marsh | SOM |
| GBYMT | Yetminster | DOR |
| GBYNY | Ynyswen | POW |
| GBYKE | Yoker | GLG |
| GBYRK | York | NYK |
| GBYGV | Youlgreave | DBY |
| GBIGN | Wrington | NSM |
| GBWRO | Wrotham | KEN |
| GBWHR | Wrotham Heath | KEN |
| GBZDN | Wroxham | NFK |
| GBQWY | Wyboston | BDF |
| GBWYY | Wybunbury | CHE |
| GBWYC | Wychbold | WOR |
| GBWYE | Wye | KEN |
| GBWKE | Wyke | BRD |
| GBWYK | Wyke Regis | DEV |
| GBWYA | Wykeham | NYK |
| GBWYM | Wylam | NBL |
| GBWMW | Wymeswold | LEC |
| GBWYD | Wymondham | NFK |
| GBWYR | Wyre | ORK |
| GBWYH | Wythenshawe | MAN |
| GBQUY | Wyton | CAM |
| GBYAL | Yalding | KEN |
| GBYAP | Yapton | WSX |
| GBYRD | Yardley | BIR |
| GBWWT | Wormelow Tump | HEF |
| GBWMH | Worminghall | BKM |
| GBWWO | Wormington | GLS |
| GBWME | Wormley | SRY |