The heather vole is among the smaller voles in Oregon. In appearance, it strongly resembles the montane vole. It is gray to brownish on the dorsum, whitish to grayish on the venter.

Two of nine nominal subspecies are purported to occur in Oregon: the lighter colored P. I. intermedius in the Blue and Wallowa mountains of northeastern Oregon and the darker P. I. oramontis in the Cascade Range.

Heather voles are rather docile creatures; they usually make little attempt to flee or to defend themselves when captured. It is active during daylight hours more frequently than the Southern red-backed vole, but is less active during the day than at twilight or night.