This opinion concerns the re-evaluation of calcium formate for use as a preservative in feed for all animal species and categories. Calcium formate is currently authorised for use as a preservative in feed for all animal species, but is not authorised as a food additive in the EU. Considering the results of the tolerance studies with chickens for fattening and cattle for fattening, and other published studies, no adverse effects on the safety for target animals are anticipated when calcium formate is used at the maximum proposed dose in feed for pigs, poultry, fish and ruminants (15 000 mg calcium formate/kg complete feed, equivalent to 10 000 mg formic acid/kg complete feed). However, no margin of safety can be established. This conclusion can be extrapolated to other animal species provided the maximum dose applied does not exceed 15 000 mg calcium formate/kg complete feed. The contribution of calcium formate to the calcium supply of animals should be considered when formulating diets. Considering that the turnover of formate is rapid, with no evidence of accumulation in body tissues, neither calcium nor formate concentrations will increase in the edible tissues of animals maintained on feed with calcium formate added and, therefore, the use of calcium formate as a feed additive in all animal species is considered safe for the consumer. Calcium formate is non-irritant to skin but causes severe adverse effects in eyes. It is likely that handling the additive could result in skin reactions and in the production of respirable dust that could present a risk to unprotected workers. The use of calcium formate in animal nutrition is safe for the environment. Data submitted do not provide convincing evidence of the efficacy of the additive when used as a preservative for compound feed or feed materials.