How to Import Your Interactive Brokers Data into Belgian Tax Calculator: The Ultimate Step by Step Guide for 2026

Introduction: Why Every Belgian IBKR User Needs This Guide

Interactive Brokers, commonly known as IBKR, has become the broker of choice for thousands of Belgian investors. With rock bottom trading fees, access to markets in over 150 countries, and a professional trading platform that rivals anything institutional traders use, it is easy to see why so many Belgians have made the switch from traditional banks like Bolero or KBC.

But here is the challenge that every Belgian IBKR user faces: the moment you open an account with Interactive Brokers, you become personally responsible for calculating, declaring, and paying all Belgian taxes on your investment activities. Unlike Belgian brokers such as Bolero, Keytrade, or BNP Paribas Fortis, Interactive Brokers does not automatically handle your Belgian tax obligations. They are an international broker serving millions of clients worldwide, and they simply cannot cater to the specific tax requirements of every country.

This creates a real problem. Belgian tax compliance for investors involves three separate taxes with different rates, different calculation methods, different deadlines, and different forms. Get any of these wrong, and you could face penalties ranging from €50 per week for late TOB declarations to potentially five times the evaded amount for intentional non-compliance.

In this guide, we will walk you through everything you need to know about importing your Interactive Brokers data into Belgian Tax Calculator. By the end, you will have a clear, practical understanding of how to export your IBKR Activity Statement, upload it to our platform, and get all your Belgian taxes calculated automatically and correctly.

Whether you have made 10 transactions or 10,000 transactions, the process takes just minutes. And once you see how much time and stress this saves compared to manual calculations, you will wonder why you ever tried to do it yourself.

Understanding Your Belgian Tax Obligations as an IBKR User

Before we dive into the import process, let us make sure you understand exactly which taxes you are dealing with. This knowledge will help you appreciate why automated calculation is so valuable.

TOB: The Tax on Stock Exchange Transactions (Beurstaks)

The first and most immediate tax every Belgian investor must handle is TOB, which stands for Taks op Beursverrichtingen in Dutch or Taxe sur les Opérations de Bourse in French. In English, we call it the Tax on Stock Exchange Transactions.

Here is how TOB works: every single time you buy or sell a security through any broker, you owe TOB to the Belgian government. This applies to both purchases and sales, so a complete round trip trade (buy then sell) means paying TOB twice.

The TOB rate depends on what type of security you are trading:

Let us look at some practical examples to understand what this means in euros:

Example 1: Buying a Stock You purchase €5,000 worth of Apple stock (AAPL). TOB calculation: €5,000 × 0.35% = €17.50

Example 2: Buying an Irish ETF You invest €10,000 in IWDA (iShares Core MSCI World UCITS ETF, domiciled in Ireland). TOB calculation: €10,000 × 0.12% = €12.00

Example 3: Hitting the Cap You make a large purchase of €500,000 worth of a Belgian stock. Raw calculation: €500,000 × 0.35% = €1,750 But the cap applies, so you pay only €1,600.

Example 4: A Belgian Accumulating Fund (Rare but Important) You buy €30,000 of a Belgian domiciled accumulating fund. TOB calculation: €30,000 × 1.32% = €396.00

The critical thing to understand is that when you use a foreign broker like Interactive Brokers, they do not calculate, withhold, or pay this tax for you. You must do it yourself, and you must do it on a monthly basis with specific deadlines.

TOB Declaration Deadlines: A Monthly Obligation

TOB declarations follow a strict schedule. The deadline for each month's transactions is the last business day of the second month following the transaction.

Here is the complete calendar:

Miss these deadlines, and you face penalties. A late declaration costs €50 per week of delay. And if the tax authorities discover undeclared transactions before you report them, the penalties become much more severe.

Dividend Withholding Tax: The 30% Rule

The second tax Belgian investors must handle is the dividend withholding tax, known as roerende voorheffing in Dutch or précompte mobilier in French. When you receive dividends from any investment, Belgium applies a 30% tax on that income.

Here is how it typically works with foreign brokers like Interactive Brokers:

1. US Dividends: When you receive dividends from US companies, the US withholds 15% at source (assuming you filed your W8BEN form). Belgium then applies its 30% tax on the gross amount, but you get a credit for the US withholding. However, this credit is limited and complicated to claim.

2. European Dividends: Various European countries withhold different amounts at source. Belgium then applies its 30% on top, though some of the foreign withholding can be credited.

3. Belgian Dividend Exemption: Belgium allows you to claim back up to €833 worth of dividends tax-free each year (this amount is indexed and may change). This is the vrijstelling roerende voorheffing or exonération précompte mobilier.

Interactive Brokers provides detailed dividend reports, but they do not calculate what you owe Belgium or what refunds you can claim. Belgian Tax Calculator handles all of this automatically when you import your data.

Capital Gains Tax: The New Reality from 2026

Starting January 1, 2026, Belgium introduced a capital gains tax on financial assets. This is the meerwaarde belasting or taxe sur les plus-values. Here is what you need to know:

Standard Rate: 10% Most capital gains from selling stocks, ETFs, and other financial instruments are taxed at 10%.

Speculative Rate: 33% If the tax authorities determine that your trading activity is speculative in nature, the rate increases to 33%. This is not simply based on holding periods. The assessment considers your trading frequency, professional background, the proportion of your wealth invested, and other factors indicating speculative intent.

Annual Exemption: €10,000 The first €10,000 of capital gains each year is exempt from tax. This exemption is indexed annually.

Maximum Exemption Pool: €15,000 Including any carryforward from previous years, the total exemption cannot exceed €15,000.

Loss Offset: Same Year Only Losses can only offset gains within the same calendar year. You cannot carry forward losses to future years.

Cost Basis Rules: Weighted Average and FIFO For positions purchased before January 1, 2026, Belgium uses the market value on December 31, 2025 as your cost basis (this is called the step-up rule). For new purchases from 2026 onwards, the First In First Out (FIFO) method applies.

Calculating capital gains manually with these rules is extremely complex, especially if you have been investing for years and have made many transactions. Belgian Tax Calculator tracks all of this automatically.

What Belgian Tax Calculator Calculates from Your IBKR Import

When you import your Interactive Brokers Activity Statement into Belgian Tax Calculator, our system processes every transaction and generates:

TOB Calculations:

• Identifies each taxable transaction (buys and sells)
• Determines the correct TOB rate based on security type and domicile
• Checks the ISIN prefix to apply the right rate (0.12%, 0.35%, or 1.32%)
• Applies the maximum cap when applicable
• Groups transactions by month for declaration purposes
• Generates the official TD-OB 01 form ready for submission
• Creates detailed per-transaction reports for your records

Dividend Tax Calculations:

• Lists all dividends received during the period
• Shows foreign withholding tax already paid
• Calculates Belgian withholding tax obligations
• Tracks your €833 exemption usage
• Determines any refund you can claim on your annual tax return

Capital Gains Tax Calculations (for 2026 and beyond):

• Tracks cost basis using weighted average for pre-2026 purchases
• Applies FIFO for post-2026 purchases
• Handles the December 31, 2025 step-up rule for existing positions
• Calculates gains and losses for each sale
• Applies the 10% standard rate
• Flags any activity that might trigger the 33% speculative rate
• Tracks your €10,000 annual exemption
• Shows net tax owed after exemptions

How to Export Your Activity Statement from Interactive Brokers

Now let us walk through the actual process of exporting your data from Interactive Brokers. This is straightforward, but following the right steps ensures you get a file that imports cleanly into Belgian Tax Calculator.

Step 1: Log Into Your Interactive Brokers Account

Open your web browser and navigate to the Interactive Brokers website at www.interactivebrokers.com. Click on "Log In" and enter your username and password. If you have two-factor authentication enabled (which you should for security), complete that verification step.

Once logged in, you will be in the Client Portal, which is IBKR's main account management interface.

Step 2: Navigate to the Reports Section

From the Client Portal dashboard, look for the main navigation menu. Click on Reports in the main menu. This opens the reporting section where you can access various statements and reports about your account activity.

Within the Reports section, click on Statements. You will see several options for different types of statements. Select Activity Statement, which contains all the transaction data we need for Belgian tax calculations.

Step 3: Select Your Date Range

The Activity Statement page allows you to specify which time period you want to export. You will see a Period dropdown menu with options like:

• Daily
• Monthly
• Year-to-Date
• Annual
• Custom Date Range

For Belgian Tax Calculator imports, we recommend selecting Custom Date Range. This gives you full control over exactly which transactions are included.

Recommended date ranges for different situations:

First time import (catching up on all history): Select the date you opened your IBKR account as the start date, and today's date as the end date. This captures your complete transaction history, which is essential for accurate capital gains calculations.

Monthly compliance: If you are importing monthly for TOB declarations, select the previous calendar month. For example, on February 15th, you would export January 1st to January 31st.

Annual tax filing: For your annual tax return, export January 1st to December 31st of the relevant tax year.

Quarterly review: Some investors prefer quarterly imports for easier tracking. Select the relevant quarter dates.

Step 4: Configure Export Options

Before downloading, there are a few important settings to check:

Account-by-Account Bundle: If this option appears, enable it by checking the box. This is particularly important if you have multiple sub-accounts or if you manage accounts for family members. The bundle option ensures each account's transactions are clearly separated in the export file.

Format Selection: You will typically see options for HTML, CSV, and PDF formats. For Belgian Tax Calculator import, we strongly recommend:

1. CSV format (Best choice): This is a clean data format that imports most reliably.
2. HTML format (Alternative): Also works well and is easier to read in a browser.
3. PDF format (Not recommended): PDF files cannot be imported as they are image-based documents.

Step 5: Download Your Activity Statement

Click the Download button (or Run/Generate, depending on the interface version). Your browser will download the Activity Statement file to your default downloads folder.

File naming: IBKR typically names the file something like "ActivityStatement_U123456_20260101_20261231.csv" where U123456 is your account number and the dates indicate the reporting period.

File location: Make note of where the file saved. You will need to find it in a moment for the upload step.

Step 6: Review the Downloaded File (Optional but Recommended)

Before importing, it is a good idea to open the file and verify it contains what you expect:

• For CSV files, you can open them in Excel or any spreadsheet program
• For HTML files, open in any web browser

Look for:

• Your transactions are listed
• The date range matches what you requested
• Both buys and sells appear
• Dividend payments are included
• Currency information is present

Uploading Your IBKR Data to Belgian Tax Calculator

Now that you have your Activity Statement file, let us walk through the import process in Belgian Tax Calculator.

Step 1: Access the Import Section

Log into your Belgian Tax Calculator account at belgiantaxcalculator.be. From your dashboard, navigate to the Import section. You will find this in the main navigation menu.

If you do not have an account yet, you can create a free account to get started. The free plan allows you to import data and see your calculations.

Step 2: Select Interactive Brokers as Your Broker

On the import page, you will see a list of supported brokers. Click on Interactive Brokers (IBKR) to select it. This tells our system which file format to expect and how to parse your transaction data.

Step 3: Upload Your File

You have two options for uploading:

1. Drag and drop: Simply drag your Activity Statement file from your file explorer and drop it onto the upload area on the page.

2. Click to browse: Click the upload button, navigate to where you saved your Activity Statement file, select it, and click Open.

The system accepts both CSV and HTML formats from Interactive Brokers.

Step 4: Wait for Processing

Once you upload the file, Belgian Tax Calculator begins processing your transactions. Depending on how many transactions are in your file, this typically takes:

• Under 100 transactions: A few seconds
• 100 to 500 transactions: 10 to 30 seconds
• 500 to 1,000 transactions: 30 seconds to 1 minute
• Over 1,000 transactions: 1 to 3 minutes

A progress indicator shows you the system is working. Do not close or refresh the page during processing.

Step 5: Review the Import Summary

After processing completes, you will see a summary showing:

• Total number of transactions found
• Number of buy transactions
• Number of sell transactions
• Dividend payments detected
• Any corporate actions (splits, mergers, etc.)
• Date range of the imported data
• Any warnings or items requiring attention

Review this summary to make sure it matches your expectations. If the numbers look significantly different from what you expected, you may want to check your export settings and try again.

Step 6: Handle Any Warnings or Questions

Sometimes the import process flags items that need your attention:

Unknown securities: If we cannot automatically identify a security, you will be asked to classify it. This happens rarely with mainstream stocks and ETFs but can occur with more exotic instruments.

Currency questions: If transactions involve currencies other than EUR, we convert them using ECB reference rates. Occasionally we might ask you to confirm a conversion if the data is ambiguous.

Duplicate detection: If you are importing data that overlaps with a previous import, the system will flag potential duplicates. You can choose to keep existing data, update with new data, or import as separate entries.

Step 7: Confirm the Import

Once you have reviewed everything and addressed any warnings, click Confirm Import. Your transactions are now saved in Belgian Tax Calculator, and all your tax calculations will update automatically.

Step 8: View Your Tax Calculations

Navigate to your dashboard to see your calculated taxes:

TOB Dashboard: Shows your monthly TOB obligations, organized by declaration period. You can download the official TD-OB 01 form for each period.

Dividend Tax Dashboard: Displays all dividends received, foreign withholding taxes, Belgian tax due, and any exemption or refund calculations.

Capital Gains Dashboard: Shows your realized gains and losses, cost basis tracking, exemption usage, and tax liability.

Real World Examples: Three IBKR Users and Their Tax Situations

Let us look at three realistic scenarios to illustrate what the import process looks like in practice and how much time Belgian Tax Calculator saves.

Example 1: Sophie, The Monthly ETF Investor

Profile: Sophie is a 32 year old software developer who invests €1,000 per month in a simple two fund portfolio: 80% IWDA (iShares Core MSCI World) and 20% EMIM (iShares Core MSCI EM). She has been doing this for three years.

Her IBKR Activity for 2026:

• 12 purchases of IWDA at approximately €800 each
• 12 purchases of EMIM at approximately €200 each
• No sales (she is a pure buy and hold investor)
• No dividends (both ETFs are accumulating)

Import Results:

Time comparison:

• Manual calculation: Approximately 30 minutes per month (identifying correct rates, filling in forms, calculating amounts) = 6 hours per year
• Belgian Tax Calculator: 5 minutes for annual import, immediate results

What Sophie gets:

• 12 monthly TD-OB 01 forms ready to submit
• Cost basis tracking for future capital gains calculations
• Complete audit trail for tax authorities

Example 2: Thomas, The Dividend Investor

Profile: Thomas is a 45 year old financial analyst who has built a dividend portfolio over 15 years. He holds 25 individual stocks across the US, Europe, and Belgium, focusing on companies with strong dividend histories.

His IBKR Activity for 2026:

• 15 stock purchases throughout the year
• 8 stock sales (rebalancing and profit taking)
• 85 dividend payments from his various holdings
• 3 dividend reinvestment purchases

Import Results:

Time comparison:

• Manual calculation: 4 to 5 hours initially, then ongoing tracking
• Belgian Tax Calculator: 10 minutes for import and review

What Thomas gets:

• Monthly TOB forms with all 23 transactions correctly categorized
• Complete dividend tax summary for his annual return
• Foreign tax credit calculations
• Capital gains report with cost basis for each sale
• €10,000 exemption tracking across all his sales

Example 3: Kevin, The Active Trader

Profile: Kevin is a 38 year old day trader who left his corporate job to trade full time. He trades US stocks, European stocks, and options, making dozens of transactions per week.

His IBKR Activity for 2026:

• 1,250 stock trades (buy and sell combined)
• 380 option trades
• 45 dividend payments
• 12 corporate actions (splits, spin-offs, etc.)

Import Results:

Time comparison:

• Manual calculation: Essentially impossible without software (200+ hours estimated)
• Belgian Tax Calculator: 15 minutes for import, 30 minutes for review

Important note for Kevin: Because of his trading volume and the fact that trading is his primary income, Kevin might be subject to the 33% speculative rate instead of the 10% standard rate. Belgian Tax Calculator flags this possibility and recommends he consult with a tax professional about his specific situation. The platform calculates both scenarios so Kevin can understand his potential liability.

Handling Special Situations

Corporate Actions: Splits, Mergers, and Spin-offs

Interactive Brokers records corporate actions in your Activity Statement, and Belgian Tax Calculator processes them automatically:

Stock Splits: When a stock splits (for example, 4:1), your cost basis is adjusted proportionally. If you bought 100 shares at €400 each (€40,000 total), after a 4:1 split you own 400 shares with a cost basis of €100 each (still €40,000 total). Belgian Tax Calculator handles this adjustment automatically.

Reverse Splits: The opposite of a split. Your share count decreases and cost per share increases proportionally.

Spin-offs: When a company spins off a division as a new company, you receive shares in the new company. The cost basis of your original holding is allocated between the parent and the spin-off based on their relative values. Belgian Tax Calculator follows the official allocation ratios.

Mergers and Acquisitions: If a company you own is acquired for stock, your cost basis transfers to the new shares. If acquired for cash, it is treated as a sale.

Currency Conversions

Interactive Brokers supports trading in multiple currencies, and many Belgian investors hold USD, GBP, and other currency positions. Here is how Belgian Tax Calculator handles this:

Transaction Currency: All transactions are converted to EUR using the European Central Bank (ECB) reference rate on the transaction date. This is the method required by Belgian tax authorities.

Example: You buy $10,000 worth of Microsoft stock on a day when the ECB rate is €1 = $1.10. EUR equivalent: $10,000 ÷ 1.10 = €9,090.91 TOB is calculated on €9,090.91

Dividends in Foreign Currency: Dividends are also converted using the ECB rate on the payment date.

Gains and Losses: Capital gains calculations use the EUR equivalent at both purchase and sale dates, which means currency movements can affect your taxable gain.

Multi-Account Situations

Many Belgian investors have multiple IBKR accounts, either for themselves or for family members:

Multiple Personal Accounts: If you have a personal account and a separate margin account, import each one. Belgian Tax Calculator consolidates them for tax purposes.

Joint Accounts: For accounts held jointly with a spouse, the tax obligations are typically split 50/50. Import the account and adjust ownership percentages in the settings.

Accounts for Children: If you manage accounts on behalf of minor children, these are taxed separately. Import them as separate portfolios in Belgian Tax Calculator.

Troubleshooting Common Issues

"File format not recognized"

Possible causes:

• You downloaded a PDF instead of CSV or HTML
• The file got corrupted during download
• You are trying to upload a Trade Confirmation instead of an Activity Statement

Solutions:

1. Go back to IBKR and export again, making sure to select CSV or HTML format
2. Ensure you are in the Statements section and selecting Activity Statement
3. Try a different browser if the download seems to be failing

"No transactions found in file"

Possible causes:

• The date range you selected had no trading activity
• The Activity Statement only includes certain sections by default
• There is a mismatch between the account and the statement

Solutions:

1. Verify the date range in your export includes periods when you made trades
2. Try expanding the date range to capture more activity
3. Check that you are logged into the correct IBKR account

"Unknown security" warnings

What this means: Belgian Tax Calculator could not automatically identify the type of security (stock, ETF, bond, etc.) or its domicile (which affects TOB rate).

How to resolve: The system will prompt you with questions about the unknown security. You can usually determine the type by:

• Checking the ISIN prefix (IE = Ireland, LU = Luxembourg, BE = Belgium, etc.)
• Looking up the security on a site like JustETF or Morningstar
• Checking your IBKR account to see how it is classified

Once you classify a security, Belgian Tax Calculator remembers it for future imports.

Duplicate transaction warnings

What this means: You are importing transactions that overlap with data you previously imported.

How to handle: You have three options:

1. Skip duplicates: Keep the existing data, only import new transactions
2. Update existing: Replace old data with the new import
3. Import all: Create duplicate entries (not recommended)

For most users, "Skip duplicates" is the best choice.

Frequently Asked Questions

How far back can I import data from IBKR?

Interactive Brokers typically provides Activity Statements going back to when you opened your account, which can be many years. With Belgian Tax Calculator's free plan, you can import up to 3 years of data across 3 portfolios. The PRO plan removes these limits.

For capital gains tax calculations starting in 2026, we recommend importing at least from January 1, 2023. This gives you sufficient history for accurate cost basis calculations.

Can I import from IBKR and other brokers together?

Yes. Belgian Tax Calculator supports importing from multiple brokers including IBKR, Degiro, Trade Republic, Bolero, and others. Simply import each broker separately, and all transactions are consolidated in your tax dashboard.

This is particularly useful if you have moved brokers over the years or use different brokers for different purposes.

What happens if I make a mistake in my import?

You can delete individual transactions or entire import batches and re-import. The system is designed to be flexible. For audit purposes, we recommend keeping your original data as accurate as possible, but corrections are straightforward if needed.

How often should I import my IBKR data?

We recommend monthly imports for the most efficient workflow. This aligns with TOB declaration periods and helps you stay current with your tax obligations.

That said, you can import as frequently or infrequently as you prefer. Some users import weekly, others quarterly, and some only import annually when preparing their tax return.

Will importing delete my existing data?

No. Imports are additive by default. The system detects potential duplicates and asks you to confirm before any data is overwritten or replaced.

What about Flex Queries? Should I use those instead?

Interactive Brokers offers both standard Activity Statements and custom Flex Queries. For Belgian Tax Calculator, we recommend the standard Activity Statement as it contains all the data we need in a consistent format.

If you are comfortable with Flex Queries and want to create a custom export, ensure you include at minimum:

• Trades section (all columns)
• Cash Transactions (for dividends)
• Corporate Actions
• Transfer and Dividend details

Does Belgian Tax Calculator handle IBKR's Tiered vs Fixed pricing?

Yes. Our calculations use the actual transaction amounts from your Activity Statement, which already reflect whatever pricing plan you use with IBKR. The TOB is calculated on the total transaction value regardless of commission structure.

What about fractional shares?

Interactive Brokers supports fractional share trading, and Belgian Tax Calculator handles these correctly. Fractional shares are taxed the same as whole shares; only the amounts differ.

Can I edit transactions after importing?

Yes. All imported transactions can be reviewed and edited if needed. You can:

• Correct security classifications
• Adjust transaction amounts
• Add notes
• Change dates if there is an error

However, we recommend keeping data as close to the source as possible for audit purposes.

What if IBKR changes their statement format?

We regularly update our import parsers to handle any changes Interactive Brokers makes to their statement formats. If you encounter issues after IBKR updates their system, try again in a day or two as we usually push fixes quickly.

Getting Started Today

Importing your Interactive Brokers data into Belgian Tax Calculator takes just minutes, but the time it saves you is measured in hours. More importantly, it eliminates the risk of errors that could result in penalties.

Here is your action plan:

1. Export your IBKR Activity Statement following the steps above
2. Create your free Belgian Tax Calculator account at belgiantaxcalculator.be
3. Upload your file and review the import summary
4. Confirm the import and explore your tax dashboard

You will immediately see:

• Your complete TOB obligations organized by month
• Ready-to-file TD-OB 01 forms
• Dividend tax calculations and exemption tracking
• Capital gains tracking with cost basis for each position

Do not spend another hour manually calculating your Belgian taxes. Let Belgian Tax Calculator do the work while you focus on what matters: building your investment portfolio.

Related Articles

If you found this guide helpful, you might also be interested in:

• TOB Declaration for Foreign Brokers: Step by Step Guide - Learn the full process for declaring and paying TOB when using any foreign broker
• Understanding ETF TOB Rates: 0.12% vs 1.32% - Discover why some ETFs are taxed at 11x higher rates and how to choose wisely
• Belgium's 2026 Capital Gains Tax: The Full Guide - Everything you need to know about the new capital gains tax regime

Last updated: February 2026

This guide is for informational purposes only and does not constitute tax advice. For complex situations, please consult a Belgian tax professional.