As of early 2018, we estimate that Russia has a stockpile of roughly 4,350 nuclear warheads assigned for use by long-range strategic launchers and shorter-range tactical nuclear forces. Of these, roughly 1,600 strategic warheads are deployed on ballistic missiles and at heavy bomber bases, while another 920 strategic warheads are in storage along with about 1,830 non-strategic warheads. In addition to the military stockpile for operational forces, a large number – perhaps almost 2,500 – of retired but still largely intact warheads await dismantlement, for a total inventory of more than 6,850 warheads The numbers indicate that Russia has reduced the warhead loading on some of its missiles to below what is normally assumed. We don’t know the breakdown of the loading because Russia, unlike the United States, does not publish an unclassified overview of its strategic forces. But the reduction potentially involved reducing the number of warheads on each SS-18 and SS-27 Mod 2 intercontinental ballistic missile (ICBM), as well as on each SS-N-32 submarine-launched ballistic missile (SLBM). This shows that New START puts real constraints on Russia’s deployed strategic forces. The result appears to be an increased reliance on a strategic reserve of non-deployed warheads that can be loaded onto missiles in a crisis to increase the size of the force, a strategy similar to the one the United States has relied on for several decades.