Anlage KAP

Anlage KAP is the attachment to the German annual income tax return (Einkommensteuererklärung) where you declare capital income — interest, dividends, and capital gains from financial instruments.

When you must file Anlage KAP

If your bank or broker has already withheld Abgeltungsteuer at source, filing Anlage KAP is optional. However, for prediction market traders using international platforms (Kalshi, Polymarket), no German tax is withheld — you must declare the income on Anlage KAP.

Key lines for prediction market traders

• Line 7: Capital gains from the sale of financial instruments (Veräußerungsgewinne)
• Line 12–13: Foreign capital income not yet taxed in Germany
• Line 16: Sparerpauschbetrag (saver's allowance) claimed

Filing with ELSTER

Anlage KAP is filed electronically through Germany's ELSTER tax portal or through tax preparation software like WISO Steuer or Taxfix. You'll need records of all prediction market trades to complete it accurately.

What records do you need?

For each prediction market position, gather:

• Purchase date and price per contract
• Settlement or sale date and proceeds
• Fees paid (transaction fees, withdrawal fees)
• Platform name and market description

Organize these into a spreadsheet showing cost basis, proceeds, and gain/loss per position. This documentation is essential if the Finanzamt (tax office) requests verification.

Frequently asked questions

What if I already paid Abgeltungsteuer through a German broker?

If tax was withheld at source, filing Anlage KAP is optional. You'd only file it to claim the Günstigerprüfung (if your personal rate is below 25%) or to apply the Sparerpauschbetrag if not already deducted.

Is Anlage KAP the same as Anlage SO?

No. Anlage KAP is for capital income (Kapitalerträge). Anlage SO (Sonstige Einkünfte) is for other income types. If prediction market gains are classified as "sonstige Einkünfte" (miscellaneous income) rather than capital income, you'd use Anlage SO instead.