American Kiger Horse Registry, Inc.
- For horses which have one or more ancestors that originated from either the Kiger Herd Management Area or the Riddle Herd Management Area. Includes information about the registry, fees, and classified advertisements.
- http://www.americankiger.com/

Southwest Spanish Mustang Association
- Formed by breeders who seek to preserve, promote, and enjoy the pure line of Spanish Mustangs. Contains list of breeders, articles, registration information, coat colors, and photos.
- http://www.southwestspanishmustangassociation.com/

The American Indian Horse Registry
- One of the largest registries for Colonial Spanish horse, and some BLM mustangs and ponies. The AIHR has different categories depending on the types of horses registered.
- http://www.indianhorse.com/

Steens Mountain Kiger Registry
- Registy for the Kiger Mustang from Steens Mountain. Includes a newsletter, FAQ page, and online studbook.
- http://www.kigers.com/smkr/

Horse of the Americas (HOA)
- An umbrella registry for all Colonial Spanish Horses. The HOA accepts horses from the Spanish Mustang Registry, the American Indian Horse Registry, and other strains identified as Colonial Spanish.
- http://www.horseoftheamericas.com/

Sulphur Horse Registry
- Registry founded in 1998 for the purpose of preserving and promoting the Sulphur Springs Mustang and its domestic progeny.
- http://sulphurhorseregistry.com/

The American Mustang and Burro Association, Inc.
- Formed in 1998 to collect, record and preserve the pedigrees of American Mustang Horses.
- http://www.bardalisa.com/

Spanish Mustang Registry Home Page
- Learn about the rich heritage, unique colors and markings of this fine breed.
- http://www.spanishmustang.org/

The Kiger Mesteño Association
- Registry founded in 1988 to protect and preserve wild Kiger mustangs and the Kiger Colonial Spanish Horse in captivity.
- http://www.kigermustangs.org/