Can Box Spread Costs Offset Capital Gains in Germany? Ask Your Steuerberater
Short answer: under current German tax law, the financing cost of a box spread ends up as a net loss on the options, and that loss is offsettable against your other capital income at the Abgeltungsteuer rate of 26.375% (about 28% with church tax). The detail is more complicated. Nothing here is tax advice — it's an explanation of where the law stands, the questions a Steuerberater can confirm for your case, and the documentation you should keep.
Where the law sits in 2026
Three pieces matter:
- §20 Abs. 1 Nr. 11 EStG makes the option premiums you receive as a writer (Stillhalterprämien) capital income. §20 Abs. 2 Satz 1 Nr. 3 EStG does the same for gains and losses from Termingeschäfte, such as a cash settlement at expiry.
- §20 Abs. 6 EStG contains the loss-offset rules. Until the 2024 change, Sätze 5 and 6 ring-fenced Termingeschäft losses: they could only offset derivative gains, and only up to €20,000 a year.
- Jahressteuergesetz 2024 (BGBl. 2024 I Nr. 387) repealed Sätze 5 and 6. That removed the whole ring-fence, including the €20,000 cap. The repeal applies to all open cases (§52 Abs. 28 EStG).
A box is not taxed as one trade. It is taxed leg by leg. The premiums you receive on the short legs are taxable Stillhalterprämien in the year you receive them. The cash settlement you pay at expiry is a Termingeschäft loss. Only both together equal your financing cost (the difference between the credit you receive at entry and the fixed amount you owe at expiry).
That net loss goes into the general capital-income pot. It offsets dividends, interest, fund income and gains from selling shares, which lowers your Abgeltungsteuer bill at 26.375% (incl. Solidaritätszuschlag). The only ring-fence left runs the other way: losses from selling shares only offset gains from selling shares. That doesn't affect the box.
What this looks like on a tax return
If you are a German tax resident with a German broker, the broker handles the tax and reports it on the year-end Steuerbescheinigung. A foreign broker like IBKR doesn't: it withholds no German tax and offsets no losses.
If your broker is non-German (no Steuerbescheinigung), you file the figures yourself in Anlage KAP. A Steuerberater is highly recommended for this — the line items have to match the German categorisation, not the foreign broker's.
This example puts everything in one tax year. A 12-month box runs past 31 December: the premiums are taxed in the year you open it, and the loss only arrives in the year it expires. The saving still comes, but possibly a year later, so plan the cash for it.
What is still uncertain
Three areas where reasonable Steuerberater might disagree, and where you should get a written opinion if the numbers are large:
- Carry-forward of losses. If you have no Kapitalerträge in the year, the loss carries forward. There is no carry-back for capital income. How the carry-forward gets used in later years is well-established but worth confirming for your specific brokerage account structure.
- Treatment in joint assessment (Zusammenveranlagung). Whether one spouse's box-spread loss can offset the other's Kapitalerträge depends on how the brokerage account is held and how the Anlage KAP is filed. Talk this through.
- Future legislative risk. JStG 2024 removed the ring-fence for all open cases, but tax law is not frozen. A future legislator could bring back a cap or re-classify. Nothing guarantees the current rule stays.
Documentation you should keep
- Trade confirmations for the four legs (broker statement, ideally as PDF or screenshot).
- Combo ticket showing the box was placed as a single complex order.
- Computation of implied rate (calculator output, screenshot of the curve as-of date).
- Steuerbescheinigung at year-end. Cross-reference to your Anlage KAP entries.
- If your broker is non-German, a copy of the foreign broker's annual statement plus your own derivation of the German categorisation.
Why this section is not advice
Tax outcomes depend on facts we don't know — your other income, your residency timeline, your spouse's filing posture, your existing loss carry-forwards, the exact legal characterisation by your local Finanzamt. A 30-minute conversation with a Steuerberater who knows derivatives is worth more than any general guide. We have a separate piece on what to ask if you need a checklist.
The bottom line
Yes — box-spread carrying costs offset Kapitalerträge under the law as it stands in 2026. The headline savings of ~26% of the cost (about 28% with church tax) are real, contingent on you having capital income to offset. If the box runs past 31 December, the saving may arrive a year later. Get the documentation right, and treat the offset as the well-supported but not unconditional benefit that it is.
See after-tax effective rates in the calculator →
Sources
- § 20 EStG: option premiums (Abs. 1 Nr. 11), Termingeschäfte (Abs. 2 Satz 1 Nr. 3), loss offsetting (Abs. 6)
- Jahressteuergesetz 2024, BGBl. 2024 I Nr. 387, Art. 3 Nr. 7: repeal of § 20 Abs. 6 Sätze 5 and 6 EStG
- § 52 Abs. 28 EStG: the repeal applies to all open cases
- BMF-Schreiben of 14 May 2025, Einzelfragen zur Abgeltungsteuer: Rz. 25–35 (options and combination trades), Rz. 118 (loss offsetting)
- BFH, 20 October 2016, VIII R 55/13: a cash settlement paid by the option writer is a loss
- § 32d EStG (25% flat tax) and § 4 SolZG (5.5% solidarity surcharge)