What's the Difference Between Cage-Free and Free-Range Eggs?

Look closely at egg cartons in the supermarket, and you'll find many marketing claims—from organic to natural, and everything in between. Two of the most common labels, “cage-free” and “free-range,” seem self-explanatory: Hens are raised without cages and with plenty of outdoor space, respectively. Right?

The ethical and environmental specifics are worth looking into. Here, we discuss the differences between cage-free and free-range eggs and where the "pasture-raised" label fits in. We also analyze the treatment of laying hens, environmental concerns, and more.

Background on the Egg Industry

The vast majority of hens are neither cage-free nor free-range but kept in battery cages—wire-secured housing systems that often contain up to four chickens (sometimes more) in a given cage. Hens kept in battery cages cannot exercise natural behaviors, such as nesting, spreading their wings, and cleaning themselves. As a result, they are more likely to develop physical disorders and experience high levels of stress.

Battery cages also prevent positive states, a subject of analysis in contemporary animal welfare science. In recent years, scientists determined that optimal animal welfare must include positive states that fall into the Five Domains of Potential Welfare Compromise: nutrition, physical environment, health, expression of behavior, and mental health. Restrictive, overpacked battery cages hinder the achievement of positive states in all five domains.  

The reported impacts of battery cages have resulted in their banning in parts of the U.S. and European countries. According to the ASPCA, only 10 U.S. states—Arizona, California, Colorado, Massachusetts, Michigan, Nevada, Oregon, Rhode Island, Utah, and Washington—have taken action toward phasing out and banning battery cages.

Understanding the "Cage-Free" Label

The “cage-free” egg label indicates that the hens producing eggs are, indeed, not confined to battery cages. However, this label alone does not guarantee the hens have access to the outdoors or, more broadly, experience positive states needed to uphold animal welfare standards.

The United States Department of Agriculture is responsible for the “organic” label on egg cartons. All other labels are either added by the producers themselves—holding few guarantees when it comes to meaningful welfare standards and accommodations for hens—or by third-party animal welfare organizations.

According to the Humane Society, third-party certifiers list the amount of space per hen needed for the cage-free label to be granted—typically, at least between one and 1.25 square feet of floor space. American Humane Certified, Certified Humane, and United Egg Producers Certified permit that hens can be kept indoors at all times with no outdoor space.

Research on Cage-Free Hens

While they provide more space than battery cages, cage-free housing systems are still insufficient, particularly for commercial hens. According to Faunalytics, bone fractures in laying hens are incredibly common regardless of the housing system. This is likely due to the egg-laying process itself, as well as the number of eggs produced by each laying hen. High egg-laying rates require substantial calcium output for hens, which can lead to avian osteoporosis and bone fragility.

Bone fractures are often not treated, reported, or even noticed in commercial facilities—which means injured hens may be in pain for the majority of their lives.

Feather pecking and cannibalism—which have been linked to genetics and learned behavior but also overcrowding and stressful environmental conditions—are also prevalent in cage-free systems. And while the lack of cages does allow for more movement, this does no good if indoor facilities are packed wall-to-wall with laying hens.

Are "Free-Range" Eggs More Ethical?

“Free-range” implies that hens are allowed to roam freely in a designated outdoor space, which automatically means these eggs are more ethical than cage-free eggs. However, “free range” without third-party certification offers no minimum space requirements or guaranteed farm inspections. 

Animal welfare organizations that grant the free-range label offer more guarantees, although some are more ethical than others. Certified Humane, for example, sets the minimum amount of outdoor space per hen at 2 square feet. On the other hand, A Greener World’s Certified Animal Welfare Approved label promises that animals are pasture-raised or free-range for their entire lives. 

Environmental Concerns

While cage-free and free-range hens are in better conditions than hens locked in battery cages, the impacts of egg farming on the environment are still significant. Overcrowded barns equal high amounts of feces, which contain ammonia and other hazardous chemicals that contribute to air pollution. Ammonia, in particular, can also add to the health consequences of laying hens, causing respiratory problems and anxiety.

In addition to the major waste problem, factory farms that keep laying hens are extraordinarily resource-intensive, requiring substantial amounts of energy for equipment and electricity.