What the U.S. Pays the U.N.
U.S. contributions to the UN in 2014 (according to the UN) totaled: $10,066,592,972
Between 2010 and December 2016, Congress failed to adopt a law requiring a report of all U.S. contributions to the United Nations. On December 16, 2016, a law was passed instituting a requirement of accounting for U.S. contributions to the UN on a regular basis.
(assessed contributions, voluntary contributions specified, voluntary contributions not specified)
There are two sources of accounting for U.S. contributions to the UN: (1) the State Department and (2) the UN itself.
According to the most recent UN data for 2014, U.S. contributions - including "assessed contributions," "voluntary contributions specified" and "voluntary contributions not specified" - totaled $10,066,592,972. The total of all UN expenses for 2014 from all sources amounted to $48,079,838,381.
The most recent State Department data sent to Congress in January 2017 does not clearly distinguish between U.S. contributions to the UN and U.S. contributions to the "International Organizations" (IO) budget, the UN amount being a subset of the overall IO budget. The total contribution to all International Organizations for 2016, according to the State Department, is $10,487,783,062.