en.wikipedia.org/wiki/Obsolete_denominations_of_United_States_currency

The United States has produced several coins and banknotes of its dollar which no longer circulate or have been disused. Many of these were removed for ...

www.uscurrency.gov/denominations/20

Hold the note to light to see an embedded thread running vertically to the left of the portrait. The thread is imprinted with the text USA TWENTY and a small flag in  ...

www.uscurrency.gov/denominations/100

Hold the note to light to see an embedded thread running vertically to the left of the portrait. The thread is imprinted with the letters USA and the numeral 100 in ...

www.federalreserve.gov/faqs/currency_12600.htm

Aug 18, 2015 ... Have a question? Ask Us. Which denominations of currency does the Federal Reserve issue? The Federal Reserve Board currently issues $1, ...

www.investopedia.com/slide-show/past-us-currency-denominations

While we can choose from an array of singles, fins, sawbucks, Jacksons and Benjamins, there are other denominations that the U.S. Treasury has discontinued.