What must taxpayers include in their gambling loss log?

Taxpayers must include all types of gambling transactions in their gambling loss log because the Internal Revenue Service (IRS) requires comprehensive documentation of gambling losses to substantiate any deductions claimed. This means that regardless of the gambling activity—whether it involves casinos, lotteries, sports betting, or informal bets—each loss must be recorded accurately along with the details of the transaction.

Maintaining a detailed gambling loss log not only helps in tracking losses but is necessary for ensuring that these losses can be claimed against gambling winnings on tax returns, up to the amount of the winnings. This accurate record-keeping reflects the total scope of gambling activities, providing a clear picture of a taxpayer's net gambling results, which is crucial for complying with tax regulations.