For a fixed rational number g / ∈ {−1, 0, 1} and integers a and d we consider the set N g (a, d) of primes p for which the order of g (mod p) is congruent to a (mod d). For d = 4 and 3 we show that, under the generalized Riemann hypothesis (GRH), these sets have a natural density g (a, d) and compute it. The results for d = 4 generalise earlier work by Chinen and Murata. The case d = 3 was apparently not considered before.