What records does the IRS accept as proof of gambling losses?

IRS Publication 529 asks for a contemporaneous diary or log showing the date, type of wager, name and address of the establishment, the people you were with, and the amounts won or lost. Supporting documents — casino win/loss statements, player-card reports, sportsbook bet-history exports, wire and bank records, W-2G forms, and losing tickets — corroborate that log but do not replace it.

Is a casino win/loss statement enough proof on its own?

No. Casinos state on the document itself that it is an estimate based only on carded play, so the IRS and the Tax Court treat it as supporting evidence rather than proof. It should back up your own session log, not substitute for it.

Does the gambling log have to be written the same day?

It must be contemporaneous, which in practice means recorded at or near the time of play — the same day is safest. Logs reconstructed at tax time from memory have been rejected in Tax Court, while same-day entries backed by bank and operator records have been accepted.

How long do I keep gambling records?

Keep the log and its supporting documents for at least three years after the filing date, which is the normal IRS assessment window. Keep six years if you may have understated income by more than 25 percent, since that extends the window.

Can I use an app or spreadsheet as my gambling log?

Yes. The IRS does not require paper. A spreadsheet or app entry is acceptable as long as it captures the Publication 529 fields, is created at the time of play, and can be tied to operator statements and bank records.

IRS Recordkeeping · 2026

Gambling Session Logs: What Records the IRS Actually Accepts

Quick answer: The IRS accepts a contemporaneous session log — date, venue, wager type, buy-in, and cash-out for each session — corroborated by operator and bank records. Win/loss statements, bet-history exports, and W-2G forms are supporting evidence. A spreadsheet rebuilt from memory in April is the single most common reason gambling-loss deductions get disallowed.

Build a session log free How the session method works

The five fields Publication 529 requires

IRS Publication 529 and Revenue Procedure 77-29 describe the same diary. Every session entry needs all five fields — missing one is what turns a log into "unsubstantiated" during an exam.

Field	What to write
Date and time	Calendar date plus session start and end time
Establishment	Casino name and address, or the app and account you played on
Type of wager	Slots, table game, poker, sportsbook, DFS, lottery
People present	Names of anyone with you (relevant for table games and syndicates)
Amounts	Total buy-in and total cash-out — the session net follows from these

What counts as supporting evidence — and how strong it is

Record	Weight with the IRS	Why
Contemporaneous session log	Primary	The record the regulations actually ask for
W-2G forms	Strong	Third-party reported; already with the IRS
Sportsbook bet-history export	Strong	Timestamped, wager-level, issued by the operator
Bank and card statements	Corroborating	Proves deposits and withdrawals, not play
Casino win/loss statement	Corroborating	Estimate based on carded play only; the casino says so on the form
Losing tickets and receipts	Weak alone	Cannot show they were yours; useful only alongside a log

What gets rejected

A spreadsheet built at tax time from memory, with round numbers and no timestamps.
A win/loss statement submitted on its own as proof of losses.
A shoebox of losing tickets with no diary tying them to sessions you played.
Net figures only — a log that shows "down $400" without the buy-in and cash-out behind it.
Losses claimed above reported winnings, which is never allowed for casual gamblers.

A session log entry that holds up

One row per session, written the day you play. This is what a defensible entry looks like:

Date	Venue	Wager type	Buy-in	Cash-out	Net	Backup
2026-09-13	DraftKings (app)	Sportsbook	$1,200	$1,950	+$750	Bet history CSV
2026-09-20	Mohegan Sun, Uncasville CT	Slots (carded)	$600	$140	−$460	Player-card report, ATM receipt

Positive session nets add up to your Schedule 1 Line 8b income. Negative session nets set the ceiling for your Schedule A loss deduction — the mechanics are covered in the IRS session method guide.

Keep it for three years minimum. The normal IRS assessment window is three years from the filing date, and six years if income was understated by more than 25%. Store the log and its backup files together, year by year, so an exam letter in 2029 doesn't send you hunting through old app accounts.

Common questions

Is a casino win/loss statement enough on its own?

No — the casino labels it an estimate of carded play. It corroborates your log; it doesn't replace it. See the win/loss statement guide for how to read one.

Does the log have to be same-day?

It has to be contemporaneous, and same-day is the safest reading. Reconstructed logs have repeatedly been rejected in Tax Court.

Can I use a spreadsheet or an app?

Yes. Nothing requires paper — only that the Publication 529 fields are captured at the time of play and can be tied to operator and bank records.

Keep the log without keeping the log

NetBetTracker timestamps every entry as you log it, imports operator CSVs, and groups activity into IRS-shaped sessions with all five Publication 529 fields.

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Informational only — not tax or legal advice. Consult a CPA or Enrolled Agent about your specific facts.