What is the biggest dollar amount on a single US bill?

The largest bill currently in circulation in the US is $100. Distribution of all larger denominations ($500, $1,000, $5,000, and $10,000) was halted in July 1969 by presidential order. Those larger bills were never recalled so they're technically still legal tender but none have been reported in circulation for decades.

Also, a $100,000 denomination printed for use within the government in the days before electronic funds transfer was possible. Various sources say up to 42,000 of them were printed; all were dated 1934. The design features a picture of President Woodrow Wilson and is distinguished by the use of orange ink.