Wingspan: 13–14 in.
Length: 3–5 in.
Weight: 0.39–0.49 oz
Color: Medium-sized bat with dull, sooty, yellow fur.
Other: Lacks distinctive white markings on its shoulders and wrists. Tail membrane is entirely furred above.
Roosting behavior: Roosts beneath hanging dead palm fronds. Does not migrate, but remains active year round except for brief periods of torpor during severe winter weather.
During the winter, northern yellow bats may undergo torpor during periods of inclement weather, though they will emerge to feed on warm evenings.