Glossary/Wash Sale Rule

Wash Sale Rule

IRS rule disallowing loss deductions if you rebuy a substantially identical security within 30 days.

The wash sale rule prevents taxpayers from claiming a capital loss if they purchase a "substantially identical" security within 30 days before or after the sale that generated the loss. The disallowed loss is added to the cost basis of the new shares.

Applicability to prediction markets

The wash sale rule's application to prediction markets is unclear. Each event contract is arguably unique — "Will Biden win the 2024 election?" is not "substantially identical" to "Will Biden win the 2028 election." However, if you sell and rebuy shares in the same market within 30 days, the IRS could potentially argue a wash sale.

Practical guidance

Most prediction market trades settle definitively (the market resolves), so there's no opportunity to rebuy. Wash sales are primarily a concern if you:

  • Sell shares of an active market to lock in a loss
  • Rebuy shares of the same market within 30 days

Our approach

predictiontaxes.com does not currently apply wash sale adjustments because the legal applicability to event contracts is unsettled. If you have concerns about specific trades, consult a tax professional.

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