Understanding the ADAS brown bird costings

Published on : 9 Jul 2026

For a growing number of producers, the ADAS Brown Free Range Egg Cost of Production and Returns figures are no longer just a reference point. They are written into contracts, with full or partial payment terms linked directly to the published costings. Given how much now rides on the numbers, BFREPA asked ADAS to prepare an annotated roundup of how the figures are actually put together, so that producers on ADAS-linked contracts can see exactly what sits behind the monthly publication.

Independence and confidentiality
ADAS collects information from a wide range of producers, packers, suppliers and other industry stakeholders, together with published sources. Individual responses are treated as strictly confidential and are never shared with other organisations or participants. ADAS reviews all of that information independently and determines the assumptions and values used in the published costings itself. Neither BFREPA nor BEIC has access to individual data submissions; both organisations only receive the completed published costings and returns. According to ADAS, this independent and confidential approach is what allows the published figures to represent an impartial, representative assessment of typical brown free range egg production costs and returns across Great Britain.

The production assumptions
The costings are based on a typical existing unit of 32,000 birds. Flock performance figures, covering egg numbers, feed intake, water use and mortality, are taken from published breed targets for the three most commonly used brown birds, with ADAS citing guides from Lohmann, Hy-Line and the Bovans Brown management guide from Joice and Hill as its reference points.

Labour requirements are calculated by ADAS itself, with costs based on industry sources and adjusted whenever changes are made to the living wage. Standard production practices required under legislation and assurance schemes, including the RSPCA scheme and the BEIC Lion Code of Practice, are assumed to achieve breed target performance. The percentage of first-quality eggs in each weight band, and the percentage of second-quality eggs, are drawn from responses supplied by egg packing centres.

The monthly market inputs
Three pieces of market information are gathered every month directly from producers, packers and others in the supply chain.

Compound feed prices are collected by ADAS providing a standard specification for a free range layer diet to a panel of feed compounders, who submit current prices covering raw material costs, manufacturing, delivery and margin. ADAS reviews the responses received and calculates a monthly average compound feed price from them.

Pullet prices are collected monthly from a range of pullet rearers, for 16-week-old birds. Those prices are based on a standard vaccination programme, with a separate allowance added on top for the typical cost of any additional vaccines.

Average egg prices paid by packers are gathered monthly, with reported prices weighted according to each packer’s approximate throughput of free range eggs. That weighting is what allows ADAS to calculate a representative average price paid for standard brown free range eggs, rather than a simple unweighted average across respondents.

Capital and finance costs
ADAS calculates a typical capital cost for existing modern buildings and equipment capable of achieving breed-standard performance. That figure is built from the assumed capital cost per bird for each year since 2017, calculated using Bank of England inflation rates, combined with the percentage annual increase in free range housing capacity over the same period where applicable. Repayment costs are then calculated using the prevailing Bank of England interest rate.

The other cost lines
ADAS states that it regularly reviews and updates every other cost line in the costings using published information and specialist input. The sources behind each are as follows:

• Electricity cost — a comparison website
• Water cost — business water rates
• Fuel cost — industry contributors
• Litter cost — industry contributors and supplier prices
• Enrichments — RSPCA scheme and BEIC Lion Code of Practice requirements, and supplier prices
• Veterinary input, medication and pest control — veterinary and other professionals
• Biosecurity — industry contributors and current supplier prices for products
• On-farm dead bird disposal by incineration — industry contributors
• Vehicle and fuel cost — trade press and UK government figures
• Egg printing consumables — equipment suppliers
• Repairs and maintenance costs — industry contributors
• Clean-out cost — industry contributors
• Range management cost — the Nix Farm Management Pocketbook and NAAC rates
• Land rental equivalent — based on Defra statistics on actual average farm rents in England
• Membership fees — for example RSPCA and BEIC Lion Code of Practice fees
• Pullet finance — industry contributors
• Office items and costs — retail prices
• Insurance — industry contributors
• Accountant fees — industry contributors
• End-of-lay hen values — poultry processors and producers
• Manure sale values — industry contributors

Where to find the full methodology
Full details of the approach used by ADAS are available to BFREPA members in documents updated monthly on the BFREPA website. For producers whose contracts are tied to the costings, that monthly documentation is the place to check exactly which assumptions have moved and why, rather than relying on the headline figure alone.

References
1. Lohmann GB free range manual
2. Hy-Line alternative guide
3. Bovans Brown management guide, Joice and Hill
4. RSPCA farm animal standards for chickens
5. BEIC Lion Code of Practice
6. Bank of England inflation calculator
7. Bank of England interest rate (Bank Rate)
8. Love Energy Savings
9. AquaSwitch business water rates
10. John Nix Pocketbook, 56th Edition, 2026
11. NAAC Contracting Prices Survey 2025
12. UK weekly road fuel prices, gov.uk