Publishers
- P. & G. Wells Ltd. 1
- P. A. Loxley-Walton 1
- P. Binstead 1
- P.A. Norstedt & Soner 1
- P.B.S. 2
- P.F. Volland Company 2
- P.I.C. 1
- P.M. (Productions) Ltd. 7
- P.M. Evans 1
- P.M. Evans And Son 2
- P.M. Heaton Publishing 7
- P.R. Gawthorn Ltd. 3
- P4 Spares 6
- Pacifica Press 2
- Paddington Press 5
- Paddington Press Ltd. 1
- Pagan World Press 1
- Palace Books 1
- Paladin Press 1
- Palgrave Macmillan 1
- Pall Mall Gazette 2
- Palores Publications 1
- Pamela Ward 1
- Pan 1
- Pan Books 3
- Pan Macmillan Children's Books 1
- Pangolin London 4
- Panico Alpinverlag 1
- Panico Press 1
- Panstwowe Muzeum Archeologiczne 1
- Pantheon Books 1
- Paolini International, Llc 1
- Papadakis 1
- Paper Tiger 2
- Paragon House 1
- Paramount Publishing Enterprise 1
- Pardy & Son Ltd. 1
- Parents' Magazine Press 1
- Parish Pump Press 3
- Parkbarn 1
- Parker, Furnivall & Parker 5
- Parkgate Books 1
- Parragon 21
- Parragon Book Service Ltd. 1
- Parragon Books 4
- Parry & Co. 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 1
- Paterson Candy Ltd 1
- Paterson Press Ltd 1
- Paterson's Publications 1
- Patrick Hardy Books 1
- Patrick Stephens 31
- Patrick Stephens Limited 48
- Paul Bernardin 1
- Paul Cave 1
- Paul Elek 1
- Paul Hamlyn 3
- Paul Harris 1
- Paul Quinn 1
- Paul Watkins 1
- Pauline Page-Jones 1
- Pavilion 9
- Pavilion Books 6
- Pavilion Books Limited 1
- Pavilion Books Ltd. 17
- Pavilion Children'S Books 2
- Payne And Mackinlay 1
- Payot 2
- Peacock Press 1
- Peak Committee Guide Book Executive 1
- Pearson 2
- Peckett & Sons, Ltd. 1
- Peco Publications 1
- Pedigree Books Limited 70
- Peebles Press 2
- Peleus Press 1
- Pelham 1
- Pelham Books 25
- Pelham Richardson 1
- Pen & Sword Aviation 6
- Pen & Sword Books 3
- Pen & Sword Maritime 3
- Pen & Sword Military 13
- Pen & Sword Transport 4
- Pen Press 1
- Pen Press Publishers Ltd. 2
- Penarth Past Oral History Group 4
- Pendragon Partnership 1
- Pendyke Publications 5
- Penguin 40
- Penguin Books 8
- Penguin Press 1
- Peninsula Press 1
- Pennine Publications Ltd. 2