Section 1256 Contracts: The Tax Rule That Splits Index Options From Stock Options
Same trade idea, different tax code section
Trade a call on SPY and a call on SPX and, mechanically, you've made a very similar directional bet on the S&P 500. At tax time, the IRS treats them nothing alike. SPY options fall under the ordinary short-term/long-term capital gains rules that apply to equity options generally. SPX options — along with a handful of other broad-based index contracts — fall under Section 1256 of the Internal Revenue Code, a completely separate regime with its own rate structure, its own year-end accounting, and its own loss rules. The underlying exposure can be nearly identical; the tax bill usually isn't.
What actually qualifies as a Section 1256 contract
Section 1256 covers regulated futures contracts, foreign currency contracts, and — the category that matters here — nonequity options, which the IRS defines to include options on a "broad-based" stock index. SPX, XSP (mini-SPX), RUT, NDX, and VIX options are the common examples: they're cash-settled and written on an index broad enough that the IRS treats them like an index future rather than a stock option. Options on SPY, QQQ, or IWM — which trade on ETF shares, not the index itself, and settle by delivering or receiving those shares — are equity options and stay under ordinary rules, even though the underlying index exposure is nearly the same. The distinction is legal form, not economic substance: cash-settled option on the index itself, versus an option on a fund that tracks the index. Cash-settled vs. physical delivery covers that settlement mechanic in more detail.
The 60/40 split
The headline feature of Section 1256 treatment is the 60/40 rule: regardless of how long the position was actually held, 60% of any gain or loss is treated as long-term capital gain or loss, and 40% is treated as short-term. For a trader whose short-term ordinary income rate is well above the long-term capital gains rate, that blended treatment can produce a meaningfully lower effective tax rate than an equity option held for the same few days or weeks — where the entire gain would be short-term. Sell an SPX call for a $1,000 gain and hold it three days, and $600 of that gain still gets long-term treatment. Do the same trade on SPY, and the full $1,000 is short-term.
Mark-to-market at year-end, whether you closed the position or not
The second feature is less flattering: Section 1256 contracts are marked to market on the last business day of the tax year. Any open position gets treated as if it were sold at fair market value on December 31, with the resulting gain or loss recognized that year under the same 60/40 split — even though nothing was actually closed. Reopen the identical position on January 2 and its new cost basis simply resets from that mark. This matters for anyone holding a longer-dated SPX spread or a LEAPS-style index position across year-end: the tax bill can show up a year before the trade is actually closed, which is a real cash-flow consideration separate from whether the trade is working.
Losses cut both ways — including backward
Section 1256 also comes with a limited loss carryback election that ordinary capital losses don't get: an individual trader can elect to carry a net Section 1256 loss back up to three prior tax years, applied only against Section 1256 gains in those years, instead of only carrying it forward. It's a narrow provision — it only offsets 1256 gains, not ordinary income — but it's a genuine mechanical advantage of trading broad-based index options over economically similar ETF options, on top of the 60/40 split. None of this changes the underlying option mechanics: strike selection, the exercise style that governs assignment risk, and position sizing all work the same way on SPX as they do on SPY. It only changes what shows up on the 1099 and the return. Traders juggling both index and equity options in the same account, or timing exits around a wash sale, should also see the wash sale rule for options, which applies to the equity-option side of a book but not to 1256 contracts.