The most useful general identification guide for the British Isles is the Seasearch Guide to Seaweeds of Britain and Ireland (2nd edn) by  Francis Bunker, Juliet A. Brodie, Christine Maggs and Anne Bunker.  Over 235 species are described in detail, with colour photographs, information on habitat, distribution and confusion species. Species are divided into three main sections, red, brown and green seaweeds, each with its own identification key and introduction. With over 550 colour photographs and illustrations this guide is an invaluable aid to any person wishing to identifying seaweeds. Available from the Marine Conservation Society for £19.50 - click here for more information.

• Bunker  FStPD, Brodie J, Maggs CA, Bunker AR (2017) Seaweeds of Britain and Ireland (Second Edition). Wild Nature Press, Plymouth. pp. [1]-312;  many colour photographs.

Introductory keys

• Hiscock S (1979) A Field Guide to the British Brown Seaweeds (Phaeophyta). Field Studies 5: 1-44.  Out of print but available for download as a pdf: fsj.field-studies-council.org/media/2775233/vol51_125a.pdf
• Hiscock S (1986) A Field Guide to the British Red Seaweeds (Rhodophyta). Field Studies 13: 1-101.  Out of print but available for download as a pdf: fsj.field-studies-council.org/media/778980/aidgap_red_seaweeds.pdf

Seaweed floras for the British Isles

• Brodie J, Irvine LM (2003) Seaweeds of Britain and Ireland, 1(3B). Rhodophyta. Bangiophycidae. Intercept, Intercept. pp. i-xiii, 1-167.
• Brodie J, Maggs CA,  John DM (2007) Green Seaweeds of Britain and Ireland. British Phycological Society, London. pp. [i-v], vi-xii, 1-242, 101 figs.
• Chamberlain YM, Irvine  LM (1994)  Seaweeds of the British Isles, 1(2B).  Rhodophyta. Corallinales, Hildenbrandiales.  HMSO,  London. pp. i-vii, 1-276. Reprinted in 2011.
• Dixon PS, Irvine LM (1977) Seaweeds of the British Isles, 1(pt 1). Rhodophyta.  Introduction, Nemaliales, Gigartinales. British Museum (Natural History), London. pp. [i]v-xi, [1]4-252, 90 figs. Reprinted in 2011.
• Fletcher RL (1987) Seaweeds of the British Isles, 3(pt 1). Fucophyceae (Phaeophyceae).  British Museum (Natural History), London. pp. [i]-x, [1]-359, 90 figs, 15 pls. Reprinted in 2011.
• Irvine LM (1983) Seaweeds of the British Isles, 1 (2A). Rhodophyta. Cryptonemiales (sensu stricto), Palmariales, Rhodymeniales. British Museum (Natural History), London. pp. [i]-xii, [1]-115. Reprinted in 2011.
• Irvine LM, Chamberlain YM (1994) Seaweeds of the British  Isles, 1 (2B). Corallinales, Hildenbrandiales. HMSO, London. pp. i-vii, [3]-276. Reprinted in 2011.
• Kristiansen J (1987) Seaweeds of the British Isles, 4. Tribophyceae (Xanthophyceae). HMSO, London. pp. 1-xiii, 1-36. Reprinted in 2011.
• Maggs CA, Howson CM (1992) A Photographic Guide to Some Common Subtidal Seaweeds of the British Isles. Marine Conservation Society, Ross on Wye. pp. 68+2.
• Maggs CA, Hommersand MH (1993) Seaweeds of the British Isles, 1 (3A). Ceramiales.  HMSO, London. pp. i-xv, [1]-444. Reprinted in 2011.

Seaweed atlas and checklist publications

• Brodie J, Wilbraham J, Pottas J, Guiry M (2016) A Revised Check-list of the Seaweeds of Britain. Journal of the Marine Biological Association of the United Kingdom, 96(5), 1005-1029. doi:10.1017/S0025315415001484
• Guiry MD (2012) A Catalogue of Irish Seaweeds. Gantner Verlag. 250 pp.
• Hardy G, Guiry MD (2006) Check-list and Atlas of the Seaweeds of Britain and Ireland. British Phycological Society. http://www.brphycsoc.org/atlas.lasso
• Morton O (1994) Marine Algae of Northern Ireland. Ulster Museum, Belfast, pp. 1-vii. [1]-123. 
• Tittley I (2016) A New Atlas of the Seaweeds of Kent: The Flora Past and Present with Summaries for Essex, London, Sussex and Pas de Calais. Kent Field Club.