A refraction seismic profile was used to determine the crustal structure across the Nain/ Makkovik boundary, and to look for an offshore continuation of the  Nain Plutonic Suite (NPS). Velocity models were developed from forward and inverse modeling of travel times. There are. In the Saglek block the crust has P-wave velocity 5.8 -6.9 km/s. Further south, upper crustal velocities iand the Poisson's ratio increase. This zone correlates with a gravity low interpreted as the NPS. The upper crustal velocities are compatible with the  NPS. There is a  lower crustal reflector under the NPS. In the Makkovik Province, upper crustal velocities are 5.9-6.2 km/s.. Moho is between 28 and 36 km. The variations may relate to Labrador Sea rifting.