UK guidance
Regulations and conservation
Rules can vary by species, location and fishing authority. Always check the current official rules before retaining a fish. Sizes and seasons in this app are copied from official pages with a retrieved date — they are not a guarantee of the law on the day you fish.
This app is not legal advice. Minimum sizes, bass rules, ray protections and local byelaws change, and they differ between England, Wales, Scotland, Northern Ireland and each IFCA district. Figures below are copied from official pages with a retrieved date.
National MCRS in this database
Source: MMO minimum conservation reference sizes in UK waters, published 3 February 2026, retrieved 9 September 2026. IFCA and nation byelaws may be stricter. Area-limited sizes (7d / 7e) are labelled as such — they are not UK-wide.
Bass MCRS 42 cm
National MCRS for bass is 42 cm (MMO table, updated 3 February 2026).
MMO — Minimum Conservation Reference Sizes (MCRS) in UK watersCod MCRS 35 cm
National MCRS for cod is 35 cm (MMO table, updated 3 February 2026).
MMO — Minimum Conservation Reference Sizes (MCRS) in UK watersHaddock MCRS 30 cm
National MCRS for haddock is 30 cm (MMO table, updated 3 February 2026).
MMO — Minimum Conservation Reference Sizes (MCRS) in UK watersWhiting MCRS 27 cm
National MCRS for whiting is 27 cm (MMO table, updated 3 February 2026).
MMO — Minimum Conservation Reference Sizes (MCRS) in UK watersPollack MCRS 30 cm
National MCRS for pollack is 30 cm (MMO table, updated 3 February 2026).
MMO — Minimum Conservation Reference Sizes (MCRS) in UK watersSaithe (coalfish) MCRS 35 cm
National MCRS for saithe is 35 cm (MMO table, updated 3 February 2026).
MMO — Minimum Conservation Reference Sizes (MCRS) in UK watersMackerel MCRS 20 cm (30 cm in the North Sea)
Mackerel MCRS is 20 cm in most UK waters and 30 cm in the North Sea (MMO table, updated 3 February 2026).
MMO — Minimum Conservation Reference Sizes (MCRS) in UK watersHorse mackerel MCRS 15 cm
National MCRS for horse mackerel (Trachurus spp.) is 15 cm (MMO table, updated 3 February 2026).
MMO — Minimum Conservation Reference Sizes (MCRS) in UK watersPlaice MCRS 27 cm
National MCRS for plaice is 27 cm (MMO table, updated 3 February 2026).
MMO — Minimum Conservation Reference Sizes (MCRS) in UK watersSole MCRS 24 cm
National MCRS for Solea spp. is 24 cm (MMO table, updated 3 February 2026).
MMO — Minimum Conservation Reference Sizes (MCRS) in UK watersLing MCRS 63 cm
National MCRS for ling is 63 cm (MMO table, updated 3 February 2026).
MMO — Minimum Conservation Reference Sizes (MCRS) in UK watersLemon sole MCRS 25 cm (7d and 7e only)
Lemon sole is listed at 25 cm in ICES 7d and 7e only (MMO table, updated 3 February 2026).
MMO — Minimum Conservation Reference Sizes (MCRS) in UK watersTurbot MCRS 30 cm (7d and 7e only)
Turbot is listed at 30 cm in ICES 7d and 7e only (MMO table, updated 3 February 2026).
MMO — Minimum Conservation Reference Sizes (MCRS) in UK watersBrill MCRS 30 cm (7d and 7e only)
Brill is listed at 30 cm in ICES 7d and 7e only (MMO table, updated 3 February 2026).
MMO — Minimum Conservation Reference Sizes (MCRS) in UK waters
Seasons, protection, licences
Bass recreational controls (time-sensitive)
MMO Bass Fishing Guidance (updated 27 February 2026) states that recreational fisheries, including from the shore, in ICES divisions 4b, 4c, 6a, 7a and 7d to 7j are limited to catch-and-release with rod and handline from 1 February to 31 March. Outside that period, recreational fishers are limited to three fish per day, as agreed in annual negotiations and amended by The Sea Fisheries (Amendment) Regulations 2026. Nursery areas can add further catch-and-release rules (The Bass (Specified Areas) (Prohibition of Fishing) Order 1990). Always read the current MMO page before you keep a bass.
MMO — Bass fishing guidanceRays — identify before you keep one
Do not keep a ray you cannot name. Undulate ray (Raja undulata) is subject to prohibition in much of southern England — it is not in this app’s target list for that reason. Local IFCA minimum sizes for thornback and others exist in some districts and not others. Check the IFCA for the coast you are standing on, and when unsure, return the fish.
Find your IFCA (inshore byelaws may be stricter)Tope — conservation first
There is no simple ‘keep at X cm’ line in the MMO MCRS finfish table for tope. Some inshore authorities and private fisheries have additional rules. Many anglers tag and return. Do not gaff a tope. Check the IFCA / nation before you even consider retaining one.
Find your IFCA (inshore byelaws may be stricter)Smoothhounds — no national MCRS in the MMO finfish table
Return small fish. They are sharks, not a bag-filler. Check the IFCA if you intend to keep one.
Find your IFCA (inshore byelaws may be stricter)European eel — do not keep
Anguilla anguilla is not a shore ‘bonus fish’. If you catch one in an estuary or river mouth, unhook it and put it back. Check Environment Agency / IFCA / DAERA / Marine Directorate / Welsh Government rules — they are not the same as bass or flounder rules. This is conservation advice plus a pointer to official sources, not a substitute for the byelaw.
Environment Agency — fishing and rod licencesSea trout — game-fish rules, not sea-fish rules
Do not treat a sea trout like a bass. In England you need a rod licence for migratory trout; seasons and method restrictions apply on many rivers and some coastal nets. Wales (sewin), Scotland and Northern Ireland have their own rules. Read the current Environment Agency / Natural Resources Wales / Marine Directorate / DAERA guidance before you target or keep one.
Get a rod fishing licence (GOV.UK)
Official sources
If you are unsure
Return the fish. Photograph it, measure it, and look it up later. Do not guess on a protected or easily-confused species. Identify by features.