A screening method was developed providing reliable detection of three chemically different β‐agonist model compounds, clenbuterol (50 ppb), salbutamol (500 ppb) and terbutaline (500 ppb). The method comprised an extraction with a mixture of acidic KH2PO4buffer plus methanol followed by detection by enzyme immunoassay using an antibody raised against clenbuterol‐diazo‐bovine serum albumin. The background signals of 107 feed samples of different composition were measured, and 86% were ≤ 2.45 ng clenbuterol equivalents g‐1. The highest values were 9–56 and 8–98 ng clenbuterol equivalents g‐1, found in two samples of mineral supplements. Analysis of spiked samples showed mean recoveries of 106 (clenbuterol) to 110% (salbutamol) and coefficients of variation of 13–22% over the different materials. Selected groups of feed materials, such as soybean meal (n =8), milk replacer (n =15), dairy concentrate (n =12), feed for poultry (n =5), protein concentrate (n =3) and ground grain meals (n =5) provided blanks all ≤ 2.58 ng clenbuterol equivalents g−1and recoveries between 97 and 124%; the coefficients of variation ranged from 4 to 14%. Although mineral supplements gave slightly less reliable results using this method with varying recoveries (22–189%) a clear differentiation of positives and negatives was always possible at the levels of interest. It may be possible to detect other β‐agonists that show cross‐reactivity with the antibody used for the immunoassay.