Part III: Slot Machine Cheating · Physical Cheating Methods

SCAM #22: Bleached/Washed Bills

How it works

A counterfeiting technique specifically designed to defeat bill validators and counterfeit detection pens. The forger takes a low-denomination genuine bill ($1 or $5), dips it in a bleaching solution until all markings are removed, leaving only the blank genuine currency paper. The blank paper is then reprinted using a laser printer with a higher-denomination design ($100). Because the paper is genuine U.S. currency paper, it passes the “pen test” (iodine-based counterfeit detection pens) and feels authentic. In 1990s Las Vegas and Atlantic City, Russian counterfeiters passed $650,000 in bleached counterfeit $100 bills into slot machines, then cashed out and received legitimate currency.

Where it appears

All bill-accepting devices, including slot machines, change machines, and kiosks.

On the record

The U.S. Secret Service estimates significant losses from washed notes annually. The “superdollar” (or “supernote”) – a counterfeit $100 bill of such high quality that it was suspected to be produced by a foreign government – caused major problems in the 2000s. When discovered, bill acceptor manufacturers issue firmware updates within hours or days to detect new counterfeits.

Published as a detection reference for surveillance, compliance and gaming-operations professionals. Thresholds and tuning are set by the property. Nothing here is instruction — the method is described so it can be recognised.