Two air-stable, isostructural, mononuclear six-coordinate manganese(II) and cobalt(II) oxamate complexes, [M(4-HOpa)(2)(H2O)(2)] [4-HOpa = N-4-hydroxyphenyloxamate; M = Mn2+ (1) or Co2+ (2)], exhibit field-induced slow magnetic relaxation. A bottleneck process is observed throughout the temperature range of 2-20 K for 1, while for 2, it dominates only at low temperatures (2-4 K). Additionally, the Raman process [n = 6.9(2)] is responsible for an increase in the relaxation time at higher temperatures to 2.