Tax Return for Investors: Claim a Refund of Withholding Tax.
Did you pay too much withholding tax? Did you forget to file an exemption form? Were your losses not offset? With the KAP form, you can claim a refund for overpaid tax. taxtastic will guide you through the process.
Why Filing a Tax Return Is Worth It for Investors
The 25% withholding tax is automatically withheld by the bank. But in many cases, you’re paying too much: exemption orders may have been forgotten or improperly allocated, losses at different banks may not have been offset, or your personal tax rate may be below 25%. With the KAP form, you can claim back the difference.
,000 saver’s allowance per person (2026)
withholding tax + solidarity surcharge + church tax (if applicable)
,000 saver’s allowance for joint filing
Here’s how the KAP investment works with taxtastic
taxtastic shows you whether the KAP investment could be worthwhile for you.
Enter investment income
Enter your annual tax statements from your banks. taxtastic assigns the values to the correct fields.
Tax Efficiency Check & Loss Offset
Is your tax rate below 25%? Do you have losses at one bank and gains at another? taxtastic calculates this for you. Here’s how loss offsetting works
Submit via ELSTER
Automatic verification and secure transmission. The tax office will refund any overpaid withholding tax along with the tax assessment notice.
What the KAP form can do for you
The KAP form checks the following points.
Most Favorable Tax Rate Test
Is your personal income tax rate below 25%? If so, taxtastic automatically applies for the more favorable tax treatment—you’ll only pay your lower rate.
Cross-bank loss offsetting
Offset losses at Bank A against gains at Bank B. To do this, you’ll need a loss certificate (apply by December 15!) and your tax return.
Forgot to file your tax exemption form?
Did you forget it or was it distributed unfavorably? You can use your tax return to claim a refund for any excess tax paid on income below the saver’s allowance.
Loss Offset for ETFs & Stocks
Offset stock losses against stock gains. Other losses (ETFs, interest) can be offset against all investment income.
Here’s how to claim a refund for overpaid taxes
A realistic example for an investor with accounts at multiple banks.
- Savings allowance: €1,000 (not fully utilized)
- Cross-bank loss offset: €1,800
- More favorable tax treatment: not applicable
- Correct church tax refund: €85
Why Investors Use taxtastic
Apply for the more favorable tax treatment test
taxtastic files the application for you; the tax office calculates which option is more favorable.
Attachment KAP is filled out automatically
Your information from the bank statements is entered into the correct fields.
Validation check
Check for errors and missing information before submission.
ELSTER transmission
Secure, direct transmission to the tax office.
Data Securely Stored in Germany
GDPR-compliant, SSL-encrypted, hosted in Germany.
Register and try it for free
See in advance how much you’ll get back. Pay only when you file.
Frequently Asked Questions
As an investor, do I have to file the KAP form?
Not always. If your bank has correctly withheld the flat-rate withholding tax and you don’t need to offset losses across banks, it’s optional. However, it’s often worth it if you’re using the “günstigerprüfung” or if you’ve forgotten to file exemption orders.
What is the “more favorable tax treatment” test?
If your personal income tax rate is below 25%, you can apply to have capital gains taxed at the lower rate. The tax office checks which option is more favorable—taxtastic submits the application automatically.
How does cross-bank loss offsetting work?
You request a loss certificate from the bank where the losses occurred by December 15. Then you include all certificates in your tax return—taxtastic automatically offsets the losses.
What happens to my carryforward losses on stocks?
Stock losses can only be offset against stock gains (loss carryforward restriction). Unoffset losses are carried forward to the next year.
How much is the saver’s allowance?
€1,000 per person, €2,000 for joint filing. Investment income up to this amount is tax-free. With an exemption order, the bank doesn’t withhold tax in the first place; without one, you can claim it back via Schedule KAP. You cannot deduct more than your investment income using the saver’s allowance: this does not result in a loss. In the case of joint taxation, the amount is halved—and whatever one of you doesn’t need, the other can deduct. In addition, no individual costs such as brokerage fees can be deducted—the flat-rate allowance takes their place.
How much does taxtastic cost?
You can use taxtastic completely free of charge until you file your tax return. Depending on the type of tax returns you want to file, you’ll pay one of our two rates, so you can see exactly in advance whether it’s worth it or not.
For employees, civil servants, retirees, etc.
- Income Tax Return
- Validation Check
- One price—even for married couples
- Previous years: 4 for voluntary returns, up to 7 for mandatory returns
- Valuable tax tips
For self-employed individuals, freelancers, etc.
- All features of the BASIS plan
- Trade tax return
- Value-Added Tax Return
- Advance sales tax return
- Automatic EÜR. Includes depreciation, IAB, and all reserves.
- Clearly track income & expenses
Find out in under 1 minute how much you’ll get back!
Our free quick check gives you an initial, non-binding estimate in just a few steps—no registration required.
How will you be taxed?
Determines the saver’s flat-rate allowance (€1,000 or €2,000).
Your Investment Income and Tax Deductions
Interest, dividends, fund distributions, capital gains from 2025.
Other income (for the more favorable tax treatment test)
If your personal tax rate is below 25%, it’s worth performing the “more favorable tax treatment” test—you’ll then pay less than the flat-rate withholding tax.