Report nitrogen and phosphorus emissions from intensive pig and poultry farms
Source: gov.uk (2025-12-04)

Calculate the annual nitrogen and phosphorus emissions from your livestock. Report the data to the Environment Agency.

If you have an environmental permit to rear pigs and poultry intensively (https://www.gov.uk/guidance/pigs-and-poultry-intensive-farming-environmental-permits), you must monitor and report your livestock’s annual:
- nitrogen (N) emissions
- phosphorus (P) emissions
When to report

You can report this annual emissions data from 1 January of each year.

You must submit your data by 28 February of each year.

What you need to report

Your N and P emissions data must cover the previous year, from 1 January to 31 December.

You must report N and P emissions for:
- broilers
- laying hens
- turkeys
- ducks (nitrogen only, not phosphorus)
- weaners (7kg to 30kg)
- fattening pigs (over 30kg)
- sows (including piglets)
You do not need to report for pullets, breeders or quails.

Report N and P data for each livestock category separately.

Emission limits

Your emissions must meet the best available techniques (BAT) associated emission levels for total N and P.

These values are given by kilogram (kg) excreted per animal place per year.

How to calculate emissions

Choose one of the 2 methods outlined in the BAT conclusions (https://bureau-industrial-transformation.jrc.ec.europa.eu/reference/intensive-rearing-poultry-or-pigs-0):
- mass balance calculation
- estimation based on manure analysis
Method 1: Mass balance calculation

Use a mass balance calculation based on:
- feed intake
- crude protein or total phosphorus content of the diet
- animal performance
Calculator tools

The Environment Agency has funded calculator tools for different farm types. Access the latest version of these and guidance on how to use them on the AHDB website: Environmental Permitting Regulations (https://ahdb.org.uk/knowledge-library/environmental-permitting-regulations).

If you use varying stocking rates throughout the year (common for broiler rearing):
- complete one calculation for each rearing cycle
- include the specific number of birds per cycle
- include the number of days in the cycle
- include the number of days between cycles
- add the results together to get your annual total
- make sure the total days equals 365
If you need help with farm-specific data, get support from your livestock supplier, nutritional specialist or trade body. For example, for feed rations or animal performance figures.

Do your own calculation

If you want to do your own mass balance calculation without the calculator tools, check section 4.9.1 of the BAT conclusions (https://bureau-industrial-transformation.jrc.ec.europa.eu/reference/intensive-rearing-poultry-or-pigs-0).

Method 2: Estimation based on manure analysis

You can estimate emissions based on manure sample analysis.

How to collect manure samples

Follow the method in section 4.9.1 of the BAT conclusions (https://bureau-industrial-transformation.jrc.ec.europa.eu/reference/intensive-rearing-poultry-or-pigs-0).

You must:
- take at least 10 sub-samples from different places or depths
- make these into one composite sample
- sample the bottom of litter for poultry
Calculate your emissions

Use this formula to convert laboratory results in kg per tonne to the required reporting units in kg per animal place per year:

(N or P2O5 value from analysis in kg per tonne × annual quantity of manure produced in tonnes) ÷ number of animal places

An example for a 100,000 place broiler farm is: (30 kg N per tonne × 1,800 tonnes) ÷ 100,000 = 0.54 kg N per animal place per year.

You must use your own site-specific data, not standard figures.

Report your emissions

Use the emissions reporting form to report the data to the Environment Agency. This form replaces the reporting template in your permit.

Make sure you complete the N and P emissions for each type of livestock you keep before you submit the form.

Start now (https://submit-form-to-defra.service.gov.uk/form/report-nitrogen-n-and-phosphorus-p-emissions-for-permitted-farms)

If you cannot use the online form, contact your Environment Agency site officer (https://www.gov.uk/government/organisations/environment-agency#org-contacts).