Publishers
- P & D Riley 1
- P. & G. Wells Ltd. 1
- P. A. Loxley-Walton 1
- P. Binstead 1
- P.A. Norstedt & Soner 1
- P.B.S. 2
- P.C. Manaktala And Sons Private Ltd 1
- P.F. Volland Company 2
- P.I.C. 1
- P.M. (Productions) Ltd. 4
- P.M. Evans 1
- P.M. Evans And Son 2
- P.M. Heaton Publishing 6
- P.R. Gawthorn Ltd. 3
- P.S. King & Son 1
- P4 Spares 5
- Pacific Air Forces 1
- Pacifica Press 2
- Paddington Press 3
- Paddington Press Ltd. 1
- Pagan World Press 1
- Palace Books 1
- Paladin Press 1
- Palamed Publishers 1
- Palaquin Publishing Ltd 1
- Palgrave Macmillan 1
- Pall Mall Gazette 2
- Pallas Athene 1
- Palores Publications 1
- Pamela Ward 1
- Pan 1
- Pan Books 2
- Pan Macmillan Children's Books 3
- Pangolin London 5
- Panico Alpinverlag 1
- Panico Press 1
- Panstwowe Muzeum Archeologiczne 1
- Pantheon Books 2
- Panther Publishing 1
- Paolini International, Llc 1
- Papadakis 1
- Paper Tiger 3
- Paragon House 1
- Paramount Publishing Enterprise 1
- Pardy & Son Ltd. 1
- Parents' Magazine Press 1
- Parish Of Tongwynlais 1
- Parkbarn 1
- Parker, Furnivall & Parker 5
- Parkgate Books 1
- Parragon 22
- Parragon Book Service Ltd. 1
- Parragon Books 4
- Parry & Co. 1
- Particular Books 1
- Partridge 16
- Partridge Press 1
- Partridge Publications Ltd. 1
- Past & Present Publishing 1
- Past and Present Publishing Ltd. 3
- Past Times 1
- Paternoster Press 2
- Paterson Press Ltd 1
- Paterson's Publications 1
- Patrick Hardy Books 2
- Patrick Hawkey 1
- Patrick Stephens 43
- Patrick Stephens Limited 52
- Paul Akermann 1
- Paul Elek 1
- Paul Hamlyn 10
- Paul Harris 1
- Paul Harris Publishing 1
- Paul Haupt 1
- Paul Watkins 2
- Pavilion 10
- Pavilion Books 8
- Pavilion Books Limited 2
- Pavilion Books Ltd. 19
- Pavilion Children'S Books 2
- Payne And Mackinlay 1
- Payot 2
- Peak Committee Guide Book Executive 1
- Pearson 2
- Peco 2
- Peco Publications 1
- Pedigree Books Limited 65
- Peebles Press 1
- Peerage Books 1
- Peleus Press 1
- Pelham Books 24
- Pelham Richardson 1
- Pembertons Publishing 1
- Pen & Sword Aviation 15
- Pen & Sword Books 3
- Pen & Sword Maritime 3
- Pen & Sword Military 18
- Pen Press 1
- Pen Press Publishers Ltd. 2
- Penarth Past Oral History Group 4