Users
- Bangladesh: HK11A1 and HK21A1 variants.
- Bolivia
- Brazil Used by the Batalhão de Operações Policiais Especiais
- Brunei: HK21A1 variant.
- Cameroon: HK21 variant.
- Denmark: Used by Jægerkorpset.
- Ecuador
- El Salvador
- Germany
- Greece: HK11A1 variant. Made under license.
- Jordan: HK21E variant.
- Kenya: HK21A1 variant.
- Malaysia: HK11A1 and HK21E variants.
- Mexico: HK21A1 variant.
- Morocco: HK11A1 variant.
- Niger: HK11 and HK21 variants.
- Nigeria: HK21 variant.
- Peru
- Portugal: HK21 variant. Made under license.
- Poland
- Qatar: HK21 variant.
- Senegal: HK21 variant.
- Sri Lanka: HK11 and HK21 variants.
- Sudan: HK21 variant.
- Sweden
- Thailand
- Turkey: HK23E variant is employed by the Turkish Gendarmerie.
- Uganda
- United Arab Emirates: HK23E variant.
- United States: Used by Delta Force in Operation Eagle Claw in 1980.
Read more about this topic: Heckler & Koch HK21