The largest paper bill denomination in USD is the $100 bill.
The $100 bill is the largest denomination of US paper currency that is currently in circulation. It features a portrait of Benjamin Franklin, one of the Founding Fathers of the United States, on the front, and an image of Independence Hall in Philadelphia on the back. The $100 bill is often referred to as a "Benjamin" or a "C-note" due to the portrait of Franklin. It is commonly used for large transactions such as buying a car or paying a large bill. In addition to being a widely accepted form of payment, the $100 bill is also a popular target for counterfeiting due to its high value. As a result, it is designed with a number of advanced security features to prevent counterfeiting and protect its integrity.