Fossnes or Valberg is a village in Sandefjord Municipality in Vestfold county, Norway. The village is located about 8 kilometres (5.0 mi) to the north of the village of Stokke and about 5 kilometres (3.1 mi) to the southeast of the village of Andebu. The city of Tønsberg lies about 10 kilometres (6.2 mi) to the east.

The 0.36-square-kilometre (89-acre) village has a population (2022) of 650 and a population density of 1,793 inhabitants per square kilometre (4,640/sq mi).

Arnadal Church is located on the north side of the village, along the river Merkadamselva.