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Commercial egg laying hens

Commercial laying hens are moved to laying farms just before they start laying eggs, at around 16 weeks old. They're typically kept until 72 weeks old, when egg production and quality declines. Here's more about how egg production works in the UK.

hens moving freely outside at an egg laying unit © RSPCA

Egg production systems

Commercial laying hens are kept in one of the following types of system.

Battery cages

Barren battery cages were banned throughout Europe from 1 January 2012, but 'enriched' battery cages are still legally permitted. Battery cages now have to provide 600cm squared useable space per bird - that's less than the size of an A4 piece of paper each - and limited facilities for perching, nesting and scratching. We don't believe this meets the full needs of the birds.

Each wire cage typically houses around 80 hens. There's no limit on how high the cage tiers can be stacked.

Barn systems

In barn systems, hens have freedom and space to move around within a building. Perches are provided for roosting, as well as material to dustbathe and forage in, and nest boxes. Some systems are 'multi-tier', providing additional levels to use above the ground.


Most free-range hens on commercial farms live in buildings like the barn system, but have access to the outside through openings called 'popholes'. EU laws require that free-range hens must always have access to an outside area with adequate vegetation during the daytime.

Egg production statistics

Around 38 million commercial egg-laying hens were kept in the UK in 2017.

In the UK, the proportion of eggs produced in the different systems in 2017 was:

  • 48%* of eggs produced in battery cages  
  • 1%* in barn systems  
  • 51%* in free-range systems (of which 2% were organic systems). 

*figures rounded up/down.

Consumers are buying more boxes of free-range and barn eggs, but a large proportion of eggs used as ingredients in products such as mayonnaise, cakes and sandwiches are still from hens kept in cages.

If you're concerned about laying hen welfare, find out how you can help.

Find out more