The IRS requires bettors to keep specific records supporting every gambling transaction. For totals bettors, that means wagering tickets, bank withdrawal slips, canceled checks, and all W-2G forms. These documents are not optional — they are the evidence that substantiates what you report on your return. See the broader framework in Legal Over Under Betting in the US: State Laws and Tax Rules.
What records does the IRS actually require totals bettors to keep?
The IRS expects a contemporaneous log — meaning records kept at the time of each wager, not reconstructed later. Supporting documentation must include wagering tickets showing the bet placed and the outcome, bank withdrawal slips or statements tied to gambling funds, canceled checks used for deposits or withdrawals, and every W-2G form issued by a sportsbook. Keep records for at least three years from the filing date, longer if your return is complex.
Do I need records even if no W-2G was issued?
Yes. All gambling winnings — including over under bet payouts — are taxable income that must be reported to the IRS regardless of whether a W-2G is issued. Casual bettors frequently under-report because they assume the W-2G is the trigger for taxation. It is not. Every winning bet is taxable income even below the reporting threshold. Failure to report is a compliance risk with the IRS. Review full threshold details at Taxes on Over Under Winnings: W-2G Thresholds and Federal Rules for 2026.
What is the W-2G threshold starting in 2026?
Starting tax year 2026, the new across-the-board W-2G reporting threshold is $2,000, changed by the 2025 federal tax bill. This replaces the prior sports-betting threshold structure. Sportsbooks must issue a W-2G when a single payout meets or exceeds this amount. Bettors should not assume this threshold reduces their reporting obligation — winnings below $2,000 remain taxable and must still be self-reported.
What documentation supports a gambling loss deduction?
Loss deductions require the same rigor as winnings. A diary or log showing dates, bet types, amounts wagered, amounts won or lost, and the sportsbook used is the IRS standard. Wagering tickets and account statements corroborate the log. Without documentation, a deduction will not survive an audit. Note that under the 2025 tax bill, the loss deduction is capped at 90% of winnings — not dollar-for-dollar. Full rules are covered at Gambling Loss Deduction for Over Under Bettors: 2026 Rules.
Does it matter which state I bet in?
State law affects where you can legally bet, not whether your winnings are federally taxable. Many states also impose their own income tax on gambling winnings and have separate reporting requirements. Legality varies significantly — check Where Is Over Under Betting Legal? State-by-State Status in 2026 to confirm your state's current status before placing any wager.
Quick-reference: records to retain
- Wagering tickets
- Printed or digital receipts showing bet placed, odds, stake, and result.
- W-2G forms
- Issued by the sportsbook when a payout meets the reporting threshold; retain every copy.
- Bank withdrawal slips
- Substantiate deposits and withdrawals linked to your betting account.
- Canceled checks
- Support any check-based transactions connected to gambling activity.
- Account statements
- Monthly or transaction-level statements from each sportsbook account used.
- Betting log or diary
- Date, sport, bet type, amount wagered, amount won or lost — kept contemporaneously.
21+ only. Gambling problem? Call 1-800-GAMBLER.