No 1099 does not mean no tax. Here is what Kalshi, Polymarket, and Robinhood actually report for 2026, and why the reporting gap is yours to close.
For the 2026 tax year, the three platforms most US traders use report almost nothing in a usable form. Here is where each one stands:
| Platform | 1099 for event contracts? | What you get |
|---|---|---|
| Kalshi | Partial | Issues some 1099-B data, but not a comprehensive form covering all event-contract trades |
| Polymarket | No | A non-custodial onchain platform; it does not issue 1099s |
| Robinhood | No | States plainly it will not provide 1099s for event-contract trades; offers an "Event Contracts Annual Statement" it labels as not a substitute for a tax form |
The reporting gap is the story. On a normal brokerage account, a 1099-B arrives in February and the numbers are mostly done for you. On prediction markets, that safety net is missing, and the obligation does not go away because the form did not show up.
This is the part that gets people in trouble. A platform not sending a 1099 is a reporting failure on their end, not a tax exemption on yours. If you realized gains trading event contracts in 2026, you are required to self-report them, with or without a form. The IRS treats unreported income as unreported income regardless of whether a third party filed paperwork.
So the practical workflow for a prediction-market trader in 2026 is:
For the per-trade economics that feed those gain calculations, the prediction market EV calculator shows the after-fee profit on each position, which is the number you are ultimately taxed on.
There is a second layer of uncertainty: even once you know your gains, it is not fully settled how they are taxed. As of late May 2026, the IRS has issued no formal prediction-market guidance. There is no Revenue Ruling, no Private Letter Ruling, and no IRS FAQ that directly resolves how CFTC-regulated event contracts are classified. That leaves traders and their preparers working from analogy to existing rules rather than from clear instruction.
We break down the competing treatments, capital versus ordinary and the Section 1256 question, in how prediction markets are taxed and event contract tax treatment. The platform-specific details live in the Kalshi 1099 guide, Robinhood event-contract 1099 guide, and Polymarket tax reporting.
Do not wait for a form that is not coming. Pull your trade exports now while the data is easy to access, keep a running record of realized gains through the year, and assume the reporting is on you. If your platform does send something, treat it as a starting point to reconcile against your own records, not as the final word.