Abstract: The total decay width of the Higgs boson has not yet been constrained precisely, which allows for up to 30% of the branching fraction to be from beyond standard model decay. If sufficiently light, dark matter motivates decay of the Higgs boson to invisible final states.

This talk will discuss searches for invisible decay of the Higgs boson produced in all production modes in pp collisions at √s= 13 TeV with the ATLAS detector, with a particular emphasis on the vector boson fusion, the most sensitive search channel. The statical combination of the different channels as well as a comparison between these searches and the constraints from the visible decay modes will be addressed. Finally, these results will be compared with direct detection dark matter experiments, assuming the Higgs portal model.