Statutory guidance

Shellfish classification

Updated 1 July 2026

Applies to England, Northern Ireland and Wales

• Publication for Scotland

The classification of a production area determines the treatment required before Live Bivalve Molluscs (shellfish) may be marketed for human consumption.

Shellfish production and relay areas are classified according to the levels of E. coli detected in shellfish flesh.

1. Permitted levels of E. coli

Levels of E. coli are measured per 100g flesh.

In all cases, the health standards are set out in:

• Annex III of assimilated Regulation (EC) 853/2004 / Regulation (EC) 853/2004
• Articles 53, 54 and 55 of assimilated Regulation (EU) 2019/627 / Regulation (EU) 2019/627

The end product microbiological criteria specified in the assimilated Regulation (EC) 2073/2005 / Regulation (EC) 2073/2005 must also be met.

The production area will be classified as A, B or C, with A as the least and C as the most contaminated. The level of treatment required to remove contamination from the Live Bivalve Molluscs (LBMs) after harvesting depends on this classification. If contamination levels are consistently so high that a class C cannot be achieved then harvesting from the area may be prohibited.

The standards that must be achieved and the level of treatment required for each classification are: 

1.1 Class A

• minimum of 10 samples required per year
• 80% of sample results must be less than or equal to 230 E. coli/100g
• no results may exceed 700 E. coli/100g

Shellfish can be harvested for direct human consumption if the end product standard requirements are met.

1.2 Class B

• minimum of 8 samples required per year
• 90% of sample results must be less than or equal to 4600 E. coli/100g
• No sample result may exceed 46000 E. coli/100g

Shellfish can be supplied for human consumption after one of three processes. The options are:

• purification in an approved establishment
• relaying for at least one month in a classified Class A relaying area
• an approved heat treatment process

England and Wales

For class B beds in England and Wales, there is a long term classification (LTC) system. This is in place to show greater stability in the classifications which are based on compliance over five years instead of the standard three years.

1.3 Class C

• minimum of 8 samples required per year
• All sample results must be less than or equal to 46000 E. coli/100g

Shellfish can only be sold for human consumption after completing one of three possible processes.

These processes are:

• relaying for at least two months in an approved class B relaying area followed by treatment in an approved purification centre
• relaying for at least two months in an approved class A relaying area
• after an approved heat treatment process

1.4 Prohibited areas

Shellfish from areas with consistently prohibited level results (greater than 46000 E. coli/100g) must not be subject to production or be harvested.

2. Shellfish purification

Shellfish can be purified (depurated) by holding them in purpose built tanks of clean or artificial seawater. The shellfish are placed in water for the time necessary to reduce contamination to make them fit for human consumption. The water conditions encourage the shellfish to filter out contaminants such as E. coli.

Dispatch centres are any on-shore or off-shore area that processes shellfish fit for human consumption.

All purification and dispatch establishments must be approved by your local authority or district council. You must meet the specific requirements for purification and dispatch centres in Annex III of assimilated Regulation (EC) 853/2004 / Regulation (EC) 853/2004.

3. Application process

3.1 Potential classification and filling out the form

If you are interested in principle to harvest/fish or relay shellfish in England, Wales and Northern Ireland, you must first apply for classification of the production area.

Please complete and submit this form electronically, along with a suitable map and any other relevant supporting information, and refrain from completing by hand. Hard or scanned copies will not be accepted.

Please note that the classification of a shellfish harvesting area does not confer the right to harvest shellfish.

You may need permissions from other bodies before proceeding. It is the responsibility of the applicant to obtain these permissions, as required, before the application is submitted to the FSA.

3.2 England and Wales

ViewApplication form for classification of a shellfish production area in England and Wales (57.2 KB)

3.3 Northern Ireland

ViewApplication form for classification of a shellfish production area in Northern Ireland

3.4 After you’ve sent the form

We  will review your application and may ask for further information or clarification. Following this review, a sanitary survey in line with regulatory requirements may be undertaken.

A sanitary survey is an assessment of the pollution sources affecting the shellfish harvesting area, to determine appropriate sampling points and a sampling plan for potential classification.

Twelve official control samples, taken over a six-month period at least two weeks apart are required for a provisional classification. After a full year of official control sampling, an annual classification may be granted.

For further information on the classification process please contact:

In England: shellfish@food.gov.uk

In Wales: shellfish.wales@food.gov.uk

In Northern Ireland: Executive.Support@food.gov.uk

4. Dealing with high results

Local action groups exist in England and Wales.

A local action group is led by your local authority and can include local industry groups, fishermen or shellfish gatherers and other stakeholders who can contribute to the investigation, e.g. the Environment Agency or Natural Resources Wales and Water Companies.

This group deal with high results and consider whether to:

• close the bed
• notify harvesters
• take action to protect public health
• liaise with FSA food incidents when necessary

For further information please refer to our Local action group guidance.

4.1 England and Wales

ViewLocal action groups guidance as PDF(Open in a new window) (349.45 KB)

4.2 Action plans

Local action plans are decided using local factors and conditions. The amount of detail in the plan will depend on:

• the number and size of shellfish beds under the responsibility of the local food authority
• any special local conditions
• the number of stakeholders involved

4.3 Action states

Action states apply to all classes of shellfish beds. It will be in place after your results have been found to be above the permitted level.

A bed may be temporarily downgraded or closed as part of short term control measures during an action state.

To re-open the bed at its previous classification, two consecutive satisfactory samples taken at least seven days apart.

We start investigating into classification results that are, for example, above the threshold for the classification awarded.

Information from DAERA, NIEA and harvesters will be asked for to try to establish the cause of the higher result and determine future action.

Any areas with results above the permitted level will be closed for harvesting.

5. Current classification list and sampling plans

5.1 England and Wales

ViewClassification List and sampling plans - 01 July 2026 as Excel(Open in a new window)

Last updated 1 July 2026.

Production area sampling plans for biotoxin and phytoplankton monitoring 

5.2 Northern Ireland

ViewNorthern Ireland Shellfish Classification List V29 as PDF(Open in a new window) (196.62 KB)

Northern Ireland Microbiological sampling schedules(Opens in a new window)

6. Supplementary information

All the areas listed are designated for species that may be harvested as well as the classification of the shellfish waters. If other species than those listed are of commercial interest then advice should be sought from the shellfish@food.gov.uk prior to any harvesting. The various species designated in the listing are as follows:

6.1 Species designated for harvest

Cerastoderma edule	Common edible cockle
Mytilus spp.	Mytilus edulis (blue mussel), Mytilus galloprovincialis (Mediterranean mussel) and hybrids
Ostrea edulis	Native or Flat Oyster
Crassostrea gigas	Pacific Oyster
Mercenaria mercenaria	Hard clam
Spisula solida	Thick trough shell
Ensis spp.	Razor clams
Pecten maximus	Great or King scallop
Mya arenaria	Gapers
Mimachlamys varia	Variegated scallop
Tapes spp.	Tapes philippinarum (Manila clam), Tapes decussatus (Palourde, native clam or carpet shell clam)

6.2 Explanatory notes

The numbers in the “Explanatory note” column indicate that additional information needs to be considered in relation to the classification status of an area.

1. Classification is provisional (for newly classified areas with less than 12-months sampling).

1c. 2019-20 sampling difficulties and shortfall in results were due to the impact of Covid-19. If other factors were also the cause of a shortfall then a 1c has been given only where the number of results missed specifically due to Covid has caused the number of samples to be less than 10 over the review year

2. Temporarily declassified because the bed is not commercially active and a reduced rate of monitoring has been agreed with the Local Authority.

3. Insufficient sample results to fully assess impact of changes in water quality, e.g. new sewerage and sewage treatment schemes, tourism factors etc.

4. Results close to the tolerance limit. A downgrade may be possible if further failures are returned.

5. Area classified at higher level as there is evidence that exceptional factors may have affected the sampling results (for example, sewage treatment works failure, greater than 1 in 5 year rainfall event etc.).

6. Area classified at lower level due to enforcement issues.

7. Bed declassified because an insufficient number of samples were received covering the review year, or for those beds that were declassified due to lack of commercial interest that are not being monitored at all (this is allowed for up to 2 years).

8. Area classified at a lower level due to results close to the tolerance limit. An upgrade may be possible if future results are favourable.

7. Classification monitoring results

England and Wales classification monitoring results(Opens in a new window)

Northern Ireland classification monitoring results(Opens in a new window)

Classification monitoring results from previous year