Publishers
- Welsh Council 1
- Welsh Educational Publishing Co. 1
- Welsh Gazette 2
- Welsh Railways Research Circle 1
- Wendy Webb Books 1
- Werner Laurie 12
- Werner Shaw Ltd. 1
- Wesleyan Conference Office 2
- Wesleyan Methodist Sunday School Union 1
- Wessex Books 1
- West Col Productions 1
- West Cornwall Field Club 1
- West Midland Bird Club 2
- West Monmouth School 1
- West, Newman & Co. 1
- Westarp Wissenschaften 1
- Westbury Publishing 1
- Western Australian Museum 1
- Western Canadian Distributors Ltd. 1
- Western Daily Press 1
- Western Mail 4
- Western Mail And Echo Limited 3
- Westerners Publications Ltd. 2
- Westerway Books 1
- Westholme Publishing 1
- Westminster Press Ltd. 2
- Westmorland Gazette 4
- Wharncliffe Books 7
- Wharncliffe Publishing Limited 2
- Wheaton 1
- Wheaton Of Exeter 1
- Wheelhouse Books 1
- Wheldon & Wesley 1
- Whitbread & Co. Ltd. 1
- Whitby Press 1
- Whitcombe and Tombs 1
- White Boar Publishing 1
- White Lion Books 1
- White Lion Publishers Limited 4
- White Mane Books 1
- White Mouse 3
- Whiting & Co. 2
- Whitman 1
- Whitman Publishing Company 11
- Whittaker & Co. 5
- Whittet Books 1
- Whittles Publishing 3
- Wicwas Press 1
- Wild Swan Publications 15
- Wildearth 2
- Wilding & Son Ltd. 6
- Wiley 5
- Wiley-Academy 1
- Wiley-Blackwell 2
- Wiley-Interscience 5
- Wilhelm Ernst & Sohn 2
- William And George North 1
- William and Robert Chambers 4
- William Andrews & Co. 3
- William Bailey 1
- William Blackwood 2
- William Blackwood & Sons Ltd. 2
- William Blackwood and Sons 8
- William Brendon And Son 1
- William Briggs 1
- William Brown 1
- William Clowes & Sons Ltd. 2
- William Collins 17
- William Collins Sons & Co. Ltd. 8
- William Darton And Son 1
- William Edwin Rudge 1
- William Graham 1
- William Heinemann 58
- William Heinemann Ltd. 41
- William Hunter 1
- William J. Hay 1
- William Kidd & Sons Ltd. 1
- William Kimber 15
- William Lewis 5
- William Lewis (Printers) Ltd 1
- William Lewis(Printers)Ltd. 2
- William Macintosh 2
- William Mackenzie 2
- William Miller 1
- William Morrow 2
- William Morrow & Company 3
- William Morrow & Company Inc 1
- William P. Nimmo 1
- William Pamplin 1
- William Phillips 1
- William Pickering 5
- William Pollard 1
- William Pollard & Co. Limited 2
- William R. Jenkins Company 1
- William Rees 1
- William Reeves 1
- William Rice 1
- William Satchell & Co. 1
- William Sessions 1
- William Smith 1