Part III: Business & Regulation · Banking, Chips & Financial Operations

35. IOU (I Owe You)

Credit & Markers

In casino terminology, an IOU is an informal acknowledgment of debt, typically a handwritten or simplified document in which a player acknowledges owing the casino money. IOUs differ from formal markers or counter checks in that they are generally not negotiable instruments and do not carry the same legal enforceability. Casinos prefer formal markers over IOUs because markers are structured credit instruments with established collection procedures. IOUs are generally discouraged or prohibited by casino internal controls and gaming regulations, as they lack the documentation and legal protections of formal credit instruments. If accepted, IOUs must be properly documented, supervisor-approved, and tracked through the casino’s credit system.

In practice

Most well-regulated casinos prohibit or severely restrict IOUs due to collection difficulties and regulatory concerns. IOUs are more commonly associated with informal credit arrangements in less regulated gaming environments.

One entry from the Casino Industry Glossary — 1,157 terms written for surveillance, compliance and operations professionals rather than for players. Definitions describe industry usage; where a term carries a regulatory meaning, verify against the instrument that governs your jurisdiction.