US EP Companies
- Accion
- Aerojet Rocketdyne
- Agile Space Industries
- Astra
- Benchmark Space Systems
- Blue Origin
- Busek
- CU Aerospace
- Earth Observant
- Exotrail
- K2 Space
- Kuiper/Amazon LEO
- Orbion
- Miles Space
- Momentus
- Morpheus
- Northrop Grumman
- Quantum Space (formerly Phase Four)
- Space Electric Thruster Systems
- SpaceX
- Stellant Inc. (formerly L-3 ETI)
International EP Companies
- Ariane Group – Germany
- Bellatrix Aerospace – India
- Enpulsion – Austria
- Exotrail: – France
- Fakel – Russia
- IHI – Japan
- Mars Space – UK
- New Orbit: – UK
- Pale Blue – Japan
- Rafael – Israel
- Safran Group – France
- Sitael S.p.A. – Italy
- Thales – Germany
- ThrustMe – France
- TsNIIMash – Russia