[3] It carries 24 Ku-band transponders at 36 MHz, which will be used to broadcast television signals to Canada, United States, Mexico, the Caribbean, and Central America.

[2] Thales Alenia Space was the prime contractor for AMC-21, and provided the satellite's communications payload.

[3] As prime contractor, Thales Alenia Space delivered the completed satellite to SES Americom.

An onboard IHI-500 N (IHI-BT4) engine then raised it to an operational geostationary orbit and placed it at a longitude of 125° West of the Greenwich Meridian.

[1] After successful completion of in-orbit testing, SES Americom took operational control of AMC-21 in September 2008.