A search for the dimuon decay of the Higgs boson was performed using data corresponding to an integrated luminosity of 36.1 fb−1 collected with the ATLAS detector in pp collisions at √s=13 TeV at the Large Hadron Collider. No significant excess is observed above the expected background. The observed (expected) upper limit on the cross section times branching ratio is 3.0 (3.1) times the Standard Model prediction at the 95% confidence level for a Higgs boson mass of 125 GeV. When combined with the pp collision data at √s=7 TeV and √s=8 TeV, the observed (expected) upper limit is 2.8 (2.9) times the Standard Model prediction.Received 15 May 2017DOI:https://doi.org/10.1103/PhysRevLett.119.051802Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.© 2017 CERN, for the ATLAS CollaborationPhysics Subject Headings (PhySH)Research AreasElectroweak interactionLeptonic, semileptonic & radiative decaysPhysical SystemsHiggs bosonsTechniquesHadron collidersParticles & Fields