Crystallisation is the moment a floating figure becomes fixed. In markets it is when an unrealised profit or loss turns into a realised one, usually because you sell, exercise, expire or close a position. In funds and pensions it can mean a fee or benefit being locked in at a specific date.
Before crystallisation, values are provisional and can move. After crystallisation they are booked, show up in realised P&L or statements, and may have tax or cash flow consequences.
What tends to trigger crystallisation?
The exact trigger depends on the product and the context, but common ones include:
- Selling or otherwise disposing of an asset, which fixes a profit or loss relative to your cost.
- Closing out a derivative, getting exercised or expiring.
- Periodic events that lock in amounts, such as a fund’s quarter end for performance fees.
- In some retirement plans, accessing benefits that are tested and recorded at that point.
- In lending, certain events can crystallise a floating charge into a fixed charge over assets.
Providers may implement these mechanics differently, so the way crystallisation appears on your account or contract can vary by platform and instrument.
Trading P&L: from unrealised to realised
On a share, ETF, crypto or FX position, price moves create unrealised P&L until you act. Sell part or all of the position and that portion of P&L is crystallised. The figure that gets booked is your sale proceeds minus your cost basis and any explicit costs such as dealing fees or financing.
Simple example: you bought 100 shares at £10 and later sell them at £14. Ignoring costs, the £400 gain is crystallised on the sale. If you sell only 50 shares, you crystallise half the gain and keep the rest unrealised.
Derivatives add a few wrinkles:
- CFDs and spread bets crystallise P&L when you close the trade. Overnight financing and any borrow fees up to that point are included in the realised result. You still carry unrealised P&L on any open legs.
- Exchange-traded futures are marked to market daily. That daily variation margin means part of your profit or loss is effectively crystallised in cash each day, even though the contract remains open.
- Options can crystallise P&L when you sell the option, when it expires, or when it is exercised and you move into the underlying. The timing affects whether the outcome shows as option P&L or rolls into the stock position.
Stops and limits simply automate the close. When a stop-loss is hit and your broker executes the sale, the loss is crystallised at the fill price, not when you placed the stop.
Tax use: crystallising capital gains or losses
Many tax systems use crystallisation language for investment disposals. A gain becomes a capital gain when it is realised, typically on a sale or other disposal. A realised loss may be recorded for potential offset against gains. The basic calculation is:
- Sale proceeds
- Minus your cost basis, including allowable acquisition and disposal costs
- Equals your realised gain or loss
For partial disposals, the cost basis of the portion sold is worked out using a method such as first in, first out, specific lots or average cost. Which method applies can vary by jurisdiction and instrument. Crypto-to-crypto exchanges, gifts or transfers may also count as disposals in some places, though the treatment differs widely.
Some investors deliberately crystallise losses near period end to offset gains, often called tax loss harvesting. This area is full of detailed rules on timing and repurchases. The specifics, including any wash sale or bed and breakfast restrictions, vary by country and can change. Rates, allowances and reliefs for capital gains tax also differ by jurisdiction and are subject to updates. Consider local rules and professional advice if you are making decisions driven by tax.
Pensions and retirement pots: benefit crystallisation
In pensions, crystallisation usually refers to the point you start taking benefits from your pot. That event locks in what you are accessing, for example a lump sum or an amount designated to drawdown, and may trigger tests against scheme limits or thresholds that apply at that time. The outcome affects how much you can take as tax free, how future contributions are treated, and how the remaining pot is recorded.
The rules around pension benefit crystallisation, available tax free amounts, and subsequent contribution limits vary by country and by scheme type, and they can change. Always check the current rules that apply to your plan before acting.
Funds, carry and performance fee crystallisation
Active funds and alternative vehicles often accrue performance fees during a period, then crystallise the fee at a set date, such as quarter or year end. At crystallisation, the fee becomes payable, typically subject to a high-water mark so the manager only earns performance fees above the previous peak value after fees.
Private equity or hedge fund arrangements may also talk about carried interest crystallising when hurdles are met or when assets are realised. Until then, carry may be accrued on paper and can be reduced by later losses. Once crystallised, it is due under the partnership or fund terms.
Other uses: charges and company finance
Lenders sometimes hold a floating charge over a borrower’s circulating assets. If specified events occur, such as default or insolvency processes, that floating charge can crystallise into a fixed charge, attaching to specific assets. The timing and consequences are governed by the security documents and local law.
Where you will see crystallisation on your account
- Trade history and statements will split realised P&L from unrealised. The realised line changes only when positions are closed or contracts settle.
- Tax reports will reference disposals and realised gains or losses. Expect to see the cost basis method used for your account.
- Fund factsheets or investor letters may show when any performance fee was crystallised and the basis used, including any high-water mark.
If you trade derivatives such as contracts for difference, be aware that providers differ on how they show accrued financing, borrow fees and realised results. The precise display and timing can vary by broker, product and region.
Common confusions to avoid
- Mark to market is not always crystallisation. It updates the carrying value. Only settlement or closure locks the outcome, except in futures where daily cash flows do that incrementally.
- Vesting is not crystallisation. Vesting makes an award yours, while crystallisation fixes the value for P&L, tax or fee purposes.
- Partial exits matter. Selling a slice crystallises only that slice, and leaves the rest exposed to market moves and tax outcomes later.
In short, crystallisation is about timing. It fixes numbers that were moving around, which is why it sits at the heart of P&L, reporting, fees and how taxes apply.