The challenging direct monoalkylation of amines with light electrophilic reagents (C₁ to C₃) was performed through a flow microreactor approach. The efficiency of mixing coupled with short residence times (t^R = 0.7–62 s) allows the transfer of a single alkyl group from R-OTf onto primary amines (R = Et, Pr) as well as on secondary amines (R = Me, Et, Pr, allyl, propargyl) with good selectivities.