Abstract The Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) has assessed seven iron compounds: ferrous carbonate, ferric chloride, hexahydrate, ferrous fumarate, ferrous sulphate, heptahydrate, ferrous sulphate, monohydrate, ferrous chelate of amino acids, hydrate and ferrous chelate of glycine, hydrate. A review of the literature concerning maximum safe levels in animals indicated that 450 mg total iron/kg appears to be safe for bovines and poultry, 600 mg total iron/kg for pet animals; these values are lower than the corresponding currently authorised maximum contents. Because of insufficient data, the FEEDAP Panel is not in a position to derive a maximum safe iron concentration in feed for horses or fish. No concerns for consumer safety are expected from the use of the iron compounds under application up to the EU maximum authorised level. Ferrous sulphates and ferric chloride hexahydrate are corrosive upon contact with mucosae and irritants to skin and respiratory tract. Ferrous fumarate, ferrous carbonate, ferrous chelate of glycine, hydrate and ferrous chelate of amino acids, hydrate are considered as irritants to skin, eyes and mucous membranes. Due to the presence of nickel, all additives under assessment should be considered as dermal and respiratory sensitisers. Handling ferrous carbonate and ferrous fumarate may lead to an iron exposure by inhalation exceeding the threshold limit value. Ferrous fumarate, ferrous carbonate and ferrous chelate of amino acids hydrate pose a risk to users by inhalation due to the levels of nickel. The supplementation of feed with the iron compounds under assessment is not expected to pose an environmental risk. The iron compounds under assessment, except ferrous carbonate, are considered efficacious sources of iron for all species and categories; ferrous carbonate has the potential to be efficacious for adult animals only.