Allen's cotton rat
Sigmodon alleni
- Vulnerable
- Card rarity: Rare
- Mammals

Allen's cotton rat is a species of rodent in the family Cricetidae. It is endemic to western Mexico, where its distribution extends from Sinaloa to Oaxaca. The formerly recognized S. planifrons and S. vulcani are now considered conspecific with S. alleni by the IUCN.
Classification
- Class
- Mammalia
- Order
- Rodentia
- Family
- Cricetidae
- Genus
- Sigmodon