This is the tax break almost nobody claims. If you had a net loss on Section 1256 contracts this year, you can carry that loss back up to three years and offset net 1256 gains you already paid tax on, generating a refund, instead of only carrying the loss forward.
Enter your current-year net 1256 loss and the net 1256 gains you reported in each of the last three years. The calculator applies the loss to the earliest year first, preserves the 60/40 character, estimates the refund at your blended rate, and shows any loss left to carry forward.
Net 1256 gains in the carryback years
Loss carried back
$7,000.00
Estimated refund
$1,526.00
at a 21.8% blended 1256 rate
Carries forward
$3,000.00
no prior gains left to absorb it
3 years ago · $4,000 in 1256 gains$4,000.00 offset → $872.00 back
2 years ago · $0 in 1256 gainsnothing to offset
1 year ago · $3,000 in 1256 gains$3,000.00 offset → $654.00 back
The loss is applied to the earliest year first, only against that year’s net 1256 gains, keeping the 60/40 character. You elect the carryback on Form 6781 and claim it with Form 1045 (or an amended 1040-X). This is an estimate, not tax advice, confirm your 1256 treatment and the exact prior-year figures with a professional.
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A net Section 1256 loss is unusual: unlike ordinary capital losses, it can be carried BACK three years, not just forward. It can only offset net 1256 gains in those years, and it is applied to the earliest of the three years first, then forward. The 60/40 long-term/short-term character carries with it.
You make the election on Form 6781 and claim the refund with Form 1045 (a quick refund application) or an amended return on Form 1040-X. Any loss that the prior gains can't absorb carries forward to future years as a 1256 loss.
Why it matters
Most trading tools only carry losses forward, so a trader who had a big 1256 gain two years ago and a loss this year leaves a real refund on the table. The blended 1256 rate (60% at the long-term rate, 40% at the ordinary rate) applied to the offset amount is roughly what comes back.
The figures here are an estimate to show whether the carryback is worth pursuing. The exact refund depends on your full return in each carryback year, so confirm with a professional before filing.
FAQ
Can Section 1256 losses be carried back?
Yes. A net Section 1256 loss can be carried back up to three years, but only against net 1256 gains in those years. You elect it on Form 6781 and claim it with Form 1045 or an amended 1040-X. Any unused loss carries forward.
How is the carryback refund calculated?
The loss offsets prior-year net 1256 gains starting with the earliest year. The refund is roughly the offset amount times your blended 1256 rate, which is 60% at the long-term capital gains rate and 40% at your ordinary rate.
What if my loss is bigger than my prior gains?
Only the portion that prior 1256 gains can absorb is carried back. Whatever is left carries forward as a Section 1256 loss to offset future 1256 gains.
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These tools are for education and estimation only, not financial or tax advice. Fee estimates use Kalshi’s standard formula and may differ from your actual fees.
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