Cost Basis & P&L
FIFO/LIFO cost basis across your positions
To know whether a position is actually winning, you need to know what it cost you. Predite computes a cost basis for every open position and uses it to show your unrealized profit and loss and your return, live, on the Portfolio page.
How cost basis is calculated
Predite uses the weighted-average method. For each market outcome you hold:
- •Every buy adds its shares and its cost (shares times price) to the running total.
- •Every sell reduces your holding at the average cost of the shares you held — not at the price you sold for — so your average entry price stays stable as you trim.
- •Your average price is total cost divided by total shares, and your cost basis for the position is shares times that average price.
This is the same method most brokerages use for a blended position, and it is deliberately not FIFO or LIFO lot matching — it answers the practical question, "what did the shares I am holding right now cost me, on average?"
What you see on the Portfolio page
For each position the portfolio shows:
- •Avg — your average entry price
- •Value — the current market value of the position
- •P&L — value minus cost basis: your unrealized gain or loss
- •P&L % — that P&L as a percentage of what you put in. (The card at the top labelled ROI is the same idea across your whole book; the column is per position.)
At the top of the page the aggregate cards are Portfolio Value, Total P&L, ROI, Open Positions and Win Rate. Note what is *not* there: a total-cost-basis card. Cost basis is a per-position column here; the rolled-up figure only appears on the Unified Portfolio. Position data comes from Polymarket, so your average price reflects your real on-chain fills.
Good to know
- •Cost basis and P&L here are unrealized — they track positions you still hold. For realized, closed-trade accounting, use the Tax Reports export. Be aware of its scope: the realized rollup covers bot trades and copy trades. Manual live orders come out in a separate per-order section and are deliberately left out of the realized total, so a book traded by hand will not be summarised there.
- •This works on every plan with a connected wallet.