Help & FAQ

Get help with using the Tax Calculator and understanding UK Capital Gains Tax.

Getting Started

You can upload transaction data in two formats:

  • QFX files: Export from Interactive Brokers activity statements
  • CSV files: Export from Sharesight or other portfolio platforms

Simply click the "Choose File" button and select your file. The calculator will automatically detect the format and process your transactions.

If uploading a CSV file, please ensure it follows this format:

DateTypeSymbolQuantityPriceFeesCurrency
2024-01-15BUYAAPL10150.005.00USD
2024-06-20SELLAAPL5180.002.00USD

Supported types: BUY, SELL, DIVIDEND, SPLIT, TRANSFER_IN, TRANSFER_OUT. Dates should be YYYY-MM-DD or DD/MM/YYYY.

The calculator follows HMRC guidelines for Capital Gains Tax:

  • Section 104 Pooling: Shares of the same class are pooled together. The cost basis is the weighted average cost of all shares in the pool.
  • Same Day & 30-Day Rules: "Bed & Breakfast" rules are applied to prevent tax avoidance by selling and repurchasing shortly after.
  • Spouse Transfers: Transfers to a spouse (TRANSFER_OUT) are handled as "no gain/no loss" disposals.
  • Share Restructuring: Stock splits and consolidations (SPLIT) automatically adjust the share pool quantity while preserving the total cost basis.
  • Allowable Costs: Broker fees and stamp duty are deducted from proceeds or added to cost basis.
  • Currency: Foreign currency transactions should be in GBP or include exchange rates in your CSV file.

Common Questions

Your financial data is processed securely and is not stored permanently on our servers.

  • Processing: Files are uploaded to our secure backend for calculation, then immediately deleted after processing
  • No Storage: We do not retain your transaction data, files, or calculation results
  • Temporary Only: Data exists only during the calculation process (typically seconds)
  • HTTPS: All data transmission is encrypted using industry-standard SSL/TLS

Our calculator follows HMRC guidelines and has been tested with various scenarios. However, always consult with a qualified tax advisor for official tax guidance.

Supported Brokers

Detailed information about CSV formats and requirements for each supported broker.

✅ Exchange Rates: Trading 212 CSVs include exchange rates - no manual conversion needed!
Expected Columns:
  • Action - Transaction type (Buy, Sell, Dividend, etc.)
  • Time - Date and time (YYYY-MM-DD HH:MM:SS)
  • ISIN - Security identifier
  • Ticker - Stock symbol
  • Name - Security name
  • No. of shares - Quantity
  • Price / share - Price per share
  • Currency (Price / share) - Transaction currency
  • Exchange rate - FX rate to GBP (if applicable)
  • Total - Total amount
  • Withholding tax, Stamp duty reserve tax, Currency conversion fee - Fees
Sample CSV Content:
Action,Time,ISIN,Ticker,Name,No. of shares,Price / share,Currency (Price / share),Exchange rate,Result,Total,Withholding tax,Currency conversion fee
Market buy,2024-01-15 14:30:00,US0378331005,AAPL,Apple Inc,10,150.00,USD,0.78,0.00,1175.00,0.00,5.00
Dividend (Ordinary),2024-03-01 10:00:00,US0378331005,AAPL,Apple Inc,10,0.24,USD,0.79,0.00,1.89,0.30,0.00
Download Sample CSV
How to Export:
  1. Log into Trading 212
  2. Go to History → Export
  3. Select date range and download CSV

ℹ️ Format: IBKR uses QFX files, not CSV. Upload your Activity Statement in QFX format.
How to Export:
  1. Log into IBKR Client Portal
  2. Go to Performance & Reports → Statements
  3. Select Activity Statement
  4. Choose date range and format: QFX
  5. Download and upload to calculator

The calculator automatically processes trades, dividends, and corporate actions from QFX files.

Standard CSV format used by Sharesight and Interactive Brokers Flex Queries.

Required Columns:
  • Symbol - Stock ticker
  • TradeDate - Transaction date
  • Buy/Sell or Code - Transaction type (Code: O=Buy, C=Sell)
  • Quantity - Number of shares
  • TradePrice or UnitPrice - Price per share
  • CurrencyPrimary - Currency (e.g., USD, GBP)
Optional Columns:
  • IBCommission or Commission - Fees
  • FXRateToBase - Exchange rate to GBP
  • AssetClass - e.g., STK, CASH
  • Description - Security name
Sample CSV Content:
Symbol,TradeDate,Buy/Sell,Quantity,TradePrice,CurrencyPrimary,IBCommission,FXRateToBase
AAPL,2024-01-15,BUY,10,150.00,USD,1.00,0.78
AAPL,2024-06-20,SELL,5,180.00,USD,1.00,0.79
MSFT,2024-03-01,DIV,1,2.50,USD,0.00,0.79

⚠️ Currency: Freetrade CSVs do NOT include exchange rates. Ensure all transactions are in GBP or manually convert foreign currency values.
Expected Columns:
  • Date - Transaction date (YYYY-MM-DD)
  • Type - BUY, SELL, DIVIDEND, etc.
  • Ticker - Stock symbol
  • Name - Security name
  • Quantity - Number of shares
  • Price - Price per share
  • Total - Total amount
  • Currency - Transaction currency (GBP, USD, EUR)
  • Fee - Trading fees
Sample CSV Content:
Date,Type,Symbol,Quantity,Price,Fees,Currency,Name
2024-01-15,BUY,AAPL,10,150.00,1.50,USD,Apple Inc
2024-06-20,SELL,AAPL,5,180.00,1.50,USD,Apple Inc
2024-03-01,DIVIDEND,AAPL,10,0.24,0.00,USD,Apple Inc
Download Sample CSV
How to Export:
  1. Open Freetrade app
  2. Go to Account → Statements
  3. Request transaction history export
  4. Download CSV file

Important: If you have USD/EUR stocks, you must manually convert prices to GBP in your CSV before uploading.

⚠️ Currency: Fidelity CSVs do NOT include exchange rates. Ensure all transactions are in GBP or manually convert foreign currency values.
Expected Columns:
  • Trade Date - Transaction date
  • Settlement Date - Settlement date
  • Action - Transaction type (YOU BOUGHT, YOU SOLD, DIVIDEND)
  • Symbol - Stock ticker
  • Security Description - Security name
  • Quantity - Number of shares
  • Price - Price per share
  • Amount - Total amount
  • Commission - Trading commission
  • Fees - Other fees
  • Settlement Currency - Currency (GBP, USD, EUR)
Sample CSV Content:
Trade Date,Settlement Date,Action,Symbol,Security Description,Quantity,Price,Amount,Settlement Currency,Commission
15/01/2024,17/01/2024,YOU BOUGHT,AAPL,APPLE INC,10,150.00,-1500.00,USD,0.00
20/06/2024,22/06/2024,YOU SOLD,AAPL,APPLE INC,5,180.00,900.00,USD,0.00
01/03/2024,01/03/2024,DIVIDEND,AAPL,APPLE INC DIVIDEND,10,0.24,2.40,USD,0.00
Download Sample CSV
Date Format:

Supports DD/MM/YYYY or YYYY-MM-DD

ℹ️ Assumption: HL converts all foreign transactions to GBP. All values are treated as GBP.
Expected Columns:
  • Date - Transaction date (DD/MM/YYYY)
  • Transaction Type - Purchase, Sale, Dividend, etc.
  • Security - Security name
  • ISIN - Security identifier
  • Quantity - Number of shares
  • Price - Price per share (may be in pence)
  • Value - Total value in GBP
  • Account Type - ISA, SIPP, etc.
Sample CSV Content:
Date,Transaction Type,Notes,Security,ISIN,Quantity,Price,Value
15/01/2024,Purchase,,Apple Inc,US0378331005,10,150.00,1500.00
20/06/2024,Sale,,Apple Inc,US0378331005,5,180.00,900.00
01/03/2024,Dividend,,Apple Inc Dividend,US0378331005,10,0.24,2.40
Download Sample CSV
Special Handling:
  • Automatically detects if prices are in pence and converts to pounds
  • ISA and SIPP accounts are flagged for tax-exempt treatment
  • No ticker symbol provided - uses ISIN or security name

If your broker isn't listed above, you can create a custom CSV with these columns:

Required Columns:
  • Date - YYYY-MM-DD or DD/MM/YYYY
  • Type - BUY, SELL, DIVIDEND, SPLIT, TRANSFER_IN, TRANSFER_OUT
  • Symbol - Stock ticker
  • Quantity - Number of shares (positive for buys, negative for sells)
  • Price - Price per share
Optional Columns:
  • Fees - Trading fees and commissions
  • Currency - Transaction currency (default: GBP)
  • Name - Security name
Sample CSV Content:
Date,Type,Symbol,Name,Quantity,Price,Fees,Currency
2024-01-15,BUY,AAPL,Apple Inc,10,150.00,1.50,GBP
2024-06-20,SELL,AAPL,Apple Inc,5,180.00,1.50,GBP
2024-03-01,DIVIDEND,AAPL,Apple Inc,10,0.24,0.00,GBP
2024-02-10,BUY,TSLA,Tesla Inc,20,200.00,5.00,GBP
Download Sample CSV
Note: For SELL transactions, you can use either a negative quantity (e.g., -5) or just "SELL" as the type with a positive quantity. The calculator handles both.

Need More Help?

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