Enables sphingosine-1-phosphate phosphatase activity. Involved in regulation of type B pancreatic cell proliferation. Predicted to be located in endoplasmic reticulum. Predicted to be active in endoplasmic reticulum membrane. Orthologous to human SGPP2 (sphingosine-1-phosphate phosphatase 2). [provided by Alliance of Genome Resources, Apr 2022]