Part III: Business & Regulation · Gambling Mathematics & Probability

51. PAR Sheet (Program Accounting Report)

Slot Math

A PAR sheet is the confidential game design document created by slot manufacturers that specifies every mathematical parameter of a slot machine, including the reel strip layouts, symbol frequencies, virtual reel mapping, paytable values, hit frequency, RTP, and volatility metrics. The PAR sheet is the “source of truth” for a game’s mathematical behavior — all actual outcomes are determined by the parameters it defines. Gaming regulators review PAR sheets during the game approval process to verify that the game meets jurisdictional requirements for minimum payout percentages. Casino surveillance and slot operations personnel may reference PAR sheets when investigating player disputes, alleged malfunctions, or unusual payout patterns. PAR sheets are considered proprietary trade secrets and are not publicly available.

In practice

“PAR” originally stood for “Program Accounting Report” or “Probability Accounting Report.” Each game title may have multiple PAR sheet versions with different RTP settings (e.g., 88%, 90%, 92%) that casinos can choose from. The term “PAR” also refers to the expected hold percentage (e.g., a 12% PAR means the game is designed to hold 12% of handle).

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.