There has been substantial productivity growth in the broiler industry; however, high growth rates might adversely affect animal welfare, resulting in calls for slow-growth breeds. This research shows production costs are 11%'25% per pound higher for slower-growing breeds than for modern breeds, depending on the target endpoint. Breakeven wholesale price premiums needed equate net returns of slow- to fast-growth broilers range from $0.10/lb to $0.36/lb. Annual costs of an industry-wide conversion to slow growth are $450 million for consumers and $3.1 billion for producers. Consumer willingness-to-pay would need to increase 10.8% to offset the producer losses.