The invention relates to allocating resources in a carrier when several subcarrier spacing configurations coexists, and more particularly to avoid or at least reduce the loss of resources when allocating in such a carrier. The invention proposes to align contiguous resource blocks (RB1) of a subcarrier spacing configuration (f1) on a raster of a different subcarrier spacing configuration (f0). Therefore the invention proposes a method to allocate such resource blocks to a terminal.