Interactive Brokers · KeSt · E1kv · Austria · 8 min read
Interactive Brokers Austria Tax: Complete Guide
Interactive Brokers (IBKR) is an Irish entity and is not tax-simple in Austria. You have to calculate your capital income yourself and report it via the E1kv supplementary form. This guide walks through the full process — from the Activity Statement to the finished tax return.
Why IBKR users must self-declare
Interactive Brokers is a foreign broker headquartered in Ireland. There is no Austrian custodian withholding KeSt automatically. Under §27a EStG 1988 your capital income is taxed at the special rate of 27.5%, but in the absence of a domestic withholding agent it must be declared in the income tax return.
Source: BMF — Income from Capital: capital income for which there is no domestic depositary or paying agent must be reported in the tax return.
Step 1: Download the Activity Statement
The Activity Statement is your master document. It contains all transactions, dividends, interest, withholding taxes and FX conversions of the year.
- Log into the IBKR Client Portal (portal.interactivebrokers.com).
- Navigate to Performance & Reports → Statements.
- Select Activity Statement, period Annual, and the relevant tax year.
- Format: PDF or CSV (CSV is machine-readable and easier to process).
Source: IBKR Tax Management & Reporting
Step 2: What you need from the statement
Dividends
All dividends received (gross). Note: IBKR often shows the net amount after foreign withholding tax — you need the gross figure.
Withholding Tax
Foreign withholding tax retained (typically US 15% with W-8BEN). Creditable against your KeSt under the Austria-USA double tax treaty.
Trades (Realized P&L)
Realised gains and losses. IBKR computes FIFO — Austria requires the moving average price (§27a Abs 4 Z 3 EStG).
Interest
Credit interest received and margin interest paid. Credit interest is taxable, margin interest is not deductible for private investors.
Corporate Actions
Stock splits, spin-offs, mergers. Can change the cost basis of your positions.
Step 3: Cost basis (moving average price)
This is where most mistakes happen. IBKR computes gains under FIFO (First In, First Out). Austria requires the moving average price— the weighted mean of all prior purchases of the same position.
Legal basis: §27a Abs 4 Z 3 EStG 1988: “For assets [...] with the same security identification number, when acquired in chronological succession, the moving average price in euros applies.”
Example:
Buy 1: 10 shares @ 100 EUR = 1,000 EUR
Buy 2: 10 shares @ 120 EUR = 1,200 EUR
Average price: (1,000 + 1,200) / 20 = 110 EUR per share
Sell: 5 shares @ 130 EUR = 650 EUR
Gain: 650 − (5 × 110) = 100 EUR taxable
Important: incidental acquisition costs (order commissions) are notdeductible when capital income is taxed at the special rate (§27a Abs 4 Z 2 EStG). The Realized P&L numbers shown by IBKR therefore cannot be taken 1:1.
Step 4: Convert foreign currencies
If you trade in USD, GBP or other currencies, all amounts must be converted to EUR at the exchange rate on the day of inflow/outflow:
- Dividends → rate on payment day
- Sale proceeds → rate on trade day
- Acquisition costs → rate on purchase day (feeds into the moving average)
ECB reference rates are at ecb.europa.eu. The Finanzamt also accepts the IBKR rates if used consistently.
Step 5: Deemed distributions (ETFs)
If you hold accumulating ETFs at IBKR, you must tax the annual deemed distributions (ausschüttungsgleiche Erträge / AgE) separately — even though IBKR does not show them in the statement (no cash flow).
You find the data on my.oekb.at — search by ISIN, take the amount per unit for the tax year and multiply by your holding on the reporting date.
Legal basis: InvFR 2018 (BMF Investment Fund Guidelines). Only reporting funds (listed on OeKB) qualify for regular treatment — non-reporting funds are subject to flat-rate replacement taxation.
Step 6: Enter the amounts in the E1kv
KZ 985
Foreign dividends and interest
Gross dividends and credit interest from the IBKR statement, in EUR.
KZ 937
Deemed distributions (foreign account)
Sum of AgE for your ETFs (from OeKB), since your account is held with a foreign broker.
KZ 994
Realised capital gains
Total gains from sales, calculated with the moving average price in EUR.
KZ 996
Realised capital losses
Total losses. Offset against gains and ongoing income within the same year.
KZ 998
Creditable foreign withholding tax
E.g. US withholding tax (15% with valid W-8BEN). Reduces your KeSt liability.
Source: BMF Form E1kv 2024 (PDF)
Loss netting
Realised losses (KZ 996) are offset against gains and ongoing income within the same calendar year. If you have multiple brokers (e.g. IBKR + Scalable), you can net losses across brokers — that is exactly what the E1kv is for.
Important: A loss carry-forward to future years is not allowed for capital income (§27 Abs 8 Z 3 EStG). Unused losses simply expire on 31 December.
US withholding tax and the double tax treaty
If you receive dividends from US companies, your broker withholds 15% US tax (with a valid W-8BEN form). Those 15% are credited against your Austrian KeSt.
Your effective tax burden: 15% (USA) + 12.5% (Austria) = 27.5% total. Without W-8BEN: 30% USA + 0% creditable in Austria = you overpay. Check in IBKR under Settings → Tax Information whether your W-8BEN is active.
Legal basis: Austria-USA Double Tax Treaty (BGBl. Nr. 232/1997)
Common mistakes by IBKR users
- FIFO instead of moving average: The Realized P&L in the IBKR statement is FIFO-based. Austria requires moving average. Numbers can differ significantly.
- Net dividends instead of gross: Some take the net figure from the statement. The E1kv requires the gross amount before foreign withholding tax.
- Forgetting deemed distributions: They are not in the IBKR statement. You have to fetch them separately from OeKB.
- Ignoring exchange rates: All amounts must be in EUR — not at year average, but at the daily rate.
- Deducting order fees: For private investors with §27a special-rate income, incidental acquisition costs are not deductible.
Filing deadline
The income tax return (incl. E1kv) is due by 30 June of the following year electronically via FinanzOnline (30 April for paper). With a tax advisor an extended quota deadline usually applies.
Source: BMF — Deadlines
Official sources
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