How Interactive Brokers calculates realized P/L
Realized P/L on an IBKR Activity Statement already includes your commissions, appears only when a position closes, and is reported per leg for options. Here is how to read it, with worked examples.
Updated October 7, 2026
Realized, unrealized and mark-to-market
- Realized P/L is locked in when you close (or an option expires). It appears on the closing trade row.
- Unrealized P/L is the paper gain or loss on positions you still hold.
- Mark-to-market (MTM) P/L measures how much positions changed in value during the statement period, whether or not they closed. It is useful for daily performance, but it is not the same as realized P/L.
Commissions are already included
IBKR adds the opening commission to the position’s cost basis, and the closing commission reduces what you receive. The realized P/L on the closing row is therefore net of both commissions. Subtracting commissions again double-counts them.
| Trade | Proceeds | Commission | Basis | Realized P/L |
|---|---|---|---|---|
| Buy 10 shares at $100 | −$1,000.00 | −$1.00 | $1,001.00 | – |
| Sell 10 shares at $110 | $1,100.00 | −$1.00 | −$1,001.00 | $98.00 |
$1,100 proceeds − $1 closing commission − $1,001 basis = $98. The $2 of commissions are inside that number.
One consequence: commissions paid on positions that are still open sit in their cost basis and do not reduce realized P/L until they close. So “commissions paid this month” and “how much commissions reduced this month’s realized P/L” can differ.
Options: premium, expiry and closing early
For a short option, the premium you receive (minus the opening commission) becomes a negative cost basis. What happens next decides the realized P/L:
- Expires worthless: IBKR books an expiration row at a price of zero. Realized P/L equals the premium net of the opening commission. Sell one call at $3.20 with a $1.05 fee and let it expire: +$318.95.
- Bought back: realized P/L is the premium minus the buy-back cost and both commissions. Sell a put at $4.50, buy it back at $9.10 with $1.05 fees each way: −$462.10.
- Assigned or exercised: IBKR typically folds the option premium into the cost basis of the resulting stock position. The option itself then shows no realized P/L; the premium appears when you sell the shares.
Multi-leg trades: spreads and iron condors
The statement reports realized P/L per leg. An iron condor closed early produces four closing rows, two usually positive and two negative. Add them together for the trade result:
| Closing leg (SPY, same expiry) | Realized P/L |
|---|---|
| Buy back short 480 put | +$62.90 |
| Sell long 475 put | −$47.10 |
| Buy back short 540 call | +$62.90 |
| Sell long 545 call | −$47.10 |
| Iron condor result | +$31.60 |
This matters for win rate. Counting legs, the trade above looks like two wins and two losses (50%). Counted as one position, it is one win. IBKR Analyzer groups option legs on the same underlying and expiry into one trade for trade counts, win rate and average win/loss, while still listing every leg.
Currencies
Each trade’s realized P/L is in the currency it traded in: US options in USD, European stocks in EUR. IBKR’s summary sections may convert to your base currency at its exchange rates, which is one reason totals can look different from the trade rows. IBKR Analyzer keeps each currency separate and never adds USD and EUR together.
Why your number might not match another report
- Base-currency translation in summary sections versus trade-currency rows.
- Different period: realized P/L counts on the closing date, so a trade opened last month and closed this month belongs to this month.
- MTM versus realized: daily performance views often use MTM.
- Dividends, interest and fees sit in their own sections and are not part of trade realized P/L.
- Corporate actions such as splits can adjust cost basis.
This guide explains how the statement reports realized P/L. It is not tax advice; tax reports apply their own rules, such as wash-sale adjustments.