Inverse Options

Updated September 26, 2026 08:01

Inverse options on Deribit are European options, settled in the base currency (BTC or ETH).

European style options are exercised only at expiry and cannot be exercised before. On Deribit, this will happen automatically at expiry. Option positions can still be closed before expiry though by trading them in the open market.

At expiry, in the money (ITM) options are first physically settled into an inverse futures contract with the same expiry, at the strike price of the option. That futures contract then settles in the base currency. The net financial result for the trader (the amount received or paid, and the currency it is settled in) is identical to a direct cash settlement. Although the options now physically settle into futures, from the trader’s perspective they can still be thought of as cash settled. When purchasing an option, the premium is immediately subtracted from the buyer’s cash balance.

The inverse options are priced in the base currency. However, the equivalent price can also be seen in USD. The price in USD is calculated by using the latest index price. Additionally, the implied volatility of the option’s price is also displayed on the platform. The implied volatility displayed uses the forward, rather than the index, as the underlying price in the calculation. Option orders can also be set in both USD and implied volatility. However, when either USD or implied volatility is used to set an inverse option price, the price of the order will then be converted to the equivalent amount of the base currency, and then rounded to the nearest valid price.

The contract multiplier for the inverse options is 1, so a BTC call option is the right to buy 1 BTC at a specific price (the strike price), and a put option is the right to sell 1 BTC at a specific price (the strike price).

The contract size of an inverse option is therefore denominated in the base currency, and order amounts are expressed in the same unit. This differs from inverse futures and inverse perpetuals, whose contract size is denominated in USD.

Settlement Process Change

From 1 August 2026, inverse (BTC and ETH settled) options settle via a two-step process rather than directly into the base currency. Any ITM option is first physically settled into an inverse futures contract with the same expiry, at the strike price, and that futures contract then cash settles in the base currency. Out of the money (OTM) options are unaffected: they expire worthless as before. Inverse options that expire on 1 August 2026 and later use this method.

What is changing

Each option expiry has a corresponding inverse futures contract for its entire lifecycle. These futures are listed at the same time as the first option contracts for each expiry.
At the moment of expiry, ITM options generate two entries in the transaction log: an entry physically settling the option into the relevant inverse futures contract (at the strike price), followed by a delivery entry for that futures contract settling into the base currency.
The futures position created by that physical settlement is denominated in USD. Its size is the option position size multiplied by the strike: position_size_future = position_size_option * strike. A long call becomes a long futures position; a long put becomes a short futures position.
OTM options that expire worthless show an "expiry" type in the transaction log instead of a delivery entry.
Any existing position on the relevant expiry future nets off against the option-generated position just before expiry. This can reduce delivery fees if there is an offsetting futures position.

What is not changing

The settlement currency remains the base currency: BTC for BTC options and ETH for ETH options.
The expiration price is still calculated as the 30-minute TWAP of the index leading into expiry, so the profit or loss of any option position is exactly the same as before.
A delivery fee is still paid on an ITM option when it physically settles into futures. The futures position generated by that physical settlement does not incur an additional delivery fee. There is no double payment for the same position.

Delivery fees

The usual delivery fee applies to an ITM option at the moment it physically settles into futures. The futures position created by this physical settlement does not itself attract an additional delivery fee.

If the option-generated futures position offsets or reduces an existing position on the expiry future, the delivery fee for the remaining futures position is lower, or zero if the position reverses direction. If there is no offsetting position, total delivery fees are the same as before. Traders therefore either pay the same delivery fees as before, or pay less.

Settlement examples

Example 1: long call, no pre-existing futures position

A trader is long one BTC call option with a strike price of $100,000. At expiry the expiration price is $125,000.

Old method: A delivery entry settles the intrinsic value into the BTC balance: 1 * (125,000 - 100,000) / 125,000 = 0.2 BTC.

New method: First, an entry physically settles the option into a BTC inverse futures contract. One BTC of exposure is purchased at an entry price of $100,000 (the strike). Because inverse futures are denominated in USD, the position size is 100,000 USD. Next, a delivery entry settles the futures profit into the cash balance: 100,000 * (1/100,000 - 1/125,000) = 0.2 BTC.

In both cases the cash balance increases by 0.2 BTC and the total delivery fee is the same, as there was no pre-existing futures position to offset.

Example 2: long put, no pre-existing futures position

A trader is long one BTC put option with a strike price of $100,000. At expiry the expiration price is $80,000.

Old method: A delivery entry settles the intrinsic value into the BTC balance: 1 * (100,000 - 80,000) / 80,000 = 0.25 BTC.

New method: First, an entry physically settles the option into a BTC inverse futures contract. One BTC of exposure is sold at an entry price of $100,000 (the strike). The inverse futures position size is -100,000 USD. Next, a delivery entry settles the futures profit into the cash balance: -100,000 * (1/100,000 - 1/80,000) = 0.25 BTC.

In both cases the cash balance increases by 0.25 BTC and the total delivery fee is the same, as there was no pre-existing futures position to offset.

API users and automated accounting should account for the brief transition from option to future during the 08:00 UTC expiry window. No manual action is required.

Trade examples

Buying a call option	A trader buys a call option with a strike price of 100,000 USD for 0.05 BTC. This call option represents the right to buy 1 BTC for 100,000 USD, though remember, in practice the options on Deribit are cash settled. At the expiry, the BTC Index is at 125,000 USD, and the delivery price is 125,000 USD. In this case, the option is settled for 25,000 USD per 1 BTC. This is calculated by subtracting the strike price minus the delivery price. 125,000 - 100,000 = 25,000 At the expiry, the trader’s account is credited with 0.2 BTC (25,000/125,000), and the seller’s account is debited with 0.2 BTC. The initial purchase price was 0.05 BTC; therefore, the trader’s profit is 0.15 BTC. Any call option with an exercise price (strike price) above 125,000 USD will expire worthless. Exercising of in the money options happens automatically at the expiry. The trader cannot exercise the option himself, or exercise it before the expiration. However, option positions can still be closed before expiry by trading them in the open market.
Buying a put option	A trader buys a put option with a strike price of 5,000 USD for 0.05 ETH. This put option represents the right to sell 1 ETH for 5,000 USD. At the expiry, the ETH Index is at 2,500 USD, and the delivery price is 2,500 USD. In this case, the option is settled for 2,500 USD per 1 ETH. This is calculated by subtracting the delivery price minus the strike price. 5,000 - 2,500 = 2,500 At the expiry, the trader’s account is credited with 1 ETH (2,500/2,500), and the seller’s account is debited with 1 ETH. The initial purchase price was 0.05 ETH; therefore, the trader’s profit is 0.95 ETH. Any put option with an exercise price (strike price) below 2,500 USD will expire worthless. Exercising of in the money options happens automatically at the expiry. The trader cannot exercise the option himself, or exercise it before the expiration. However, option positions can still be closed before expiry though by trading them in the open market.
Selling a call option	A trader sells a call option with a strike price of 100,000 USD for 0.05 BTC. At the expiry, the BTC Index is at 95,000 USD, and the delivery price is 95,000 USD. The option expires worthless as the delivery price is below the strike price of the call option. The buyer lost 0.05 BTC, and the seller gained 0.05 BTC.
Selling a put option	A trader sells a put option with a strike price of 5,000 USD for 0.05 ETH. At the expiry, the ETH Index is at 6,000 USD, and the delivery price is 6,000 USD. The option expires worthless as the delivery price is above the strike price of the put option. The buyer lost 0.05 ETH, and the seller gained 0.05 ETH.

Inverse Option Contract specifications

Inverse options	BTC	ETH
Symbol	BTC-DDMMMYY-STRIKE-SIDE Date: (2 numbered date, 3 letters of month, 2 numbers of year) Strike: Strike price of the underlying asset Side: Either 'C' (call) or 'P' (put)	ETH-DDMMMYY-STRIKE-SIDE Date: (2 numbered date, 3 letters of month, 2 numbers of year) Strike: Strike price of the underlying asset Side: Either 'C' (call) or 'P' (put)
Underlying Asset / Ticker	Deribit BTC Index	Deribit ETH Index
Underlying future	The forward price for an expiry is the corresponding future's mark price. If there is no corresponding future a synthetic future is used.
Type	Inverse	Inverse
Category	Option	Option
Trading hours	24/7	24/7
Quoted Currency	BTC (The USD equivalent is shown in the orderbook, based on the BTC index)	ETH (The USD equivalent is shown in the orderbook, based on the ETH index)
Margin Currency	BTC	ETH
Strike price intervals	Please see contract introduction policy
Strike prices	In the money (ITM) , at the money (ATM) and out of the money (OTM) strike prices are initially listed. New series are generally added when the underlying asset trades above the highest or below the lowest strike price available.
Contract Multiplier Values	1 BTC Each contract represents 1 BTC. The premium is shown for 1 BTC.	1 ETH Each contract represents 1 ETH. The premium is shown for 1 ETH.
Initial Margin	The initial margin is calculated as the amount of margin currency that will be reserved to open a position. Standard margin account: Long Call/Put: The premium for a long option is paid in full, at the moment of purchase, from your cash balance. Other than the premium paid, there are no further margin requirements for a long option in a Standard Margin (SM) account. Short Call: MAX(0.15 - MAX((Strike - Index)/Index, 0), 0.1) + Mark Price of the Option Short Put: MAX(MAX(0.15 - MAX(Index - Strike, 0)/Index, 0.1) + Mark Price of the Option, Maintenance Margin)
Maintenance Margin	The maintenance margin is calculated as the amount of margin currency that will be reserved to maintain a position. Standard margin account: Long call/put: The premium for a long option is paid in full, at the moment of purchase, from your cash balance. If the option has a positive result the PNL is locked in the position and can not be withdrawn or utilized to cover other positions. Other than the premium paid & positive result of the option, there are no further margin requirements for a long option in a Standard Margin (SM) account. Short Call: 0.075 + Mark Price of the Option Short Put: MAX(0.075, 0.075 * Mark Price of the Option) + Mark Price of the Option
Mark price	Mark price of an options contract is the current value of the option as calculated by the Deribit risk management system. Usually, this is the average of the best bid and best ask price. However, for risk management purposes, there are other checks and bandwidths in place.
Delivery price	Time-weighted average of Deribit index as measured between 07:30 and 08:00 UTC.
Exercise style	European style with a cash settlement. European style options are exercised at the expiry. This is done automatically and no action from the trader is required.
Exercise Settlement Value	Exercise of an inverse options contract will result in a settlement in the margin currency immediately after the expiry. The exercise settlement value is calculated using the delivery price. The settlement amount in USD is equal to the difference between the delivery price and the strike price of the option. The settlement amount in the underlying asset is calculated by dividing this difference by the settlement value.
Settlement method	Cash settlement in BTC.	Cash settlement in ETH.
Settlement	Daily at 8:00 AM UTC	Daily at 8:00 AM UTC
Expiration dates	Daily at 8:00 AM UTC	Daily at 8:00 AM UTC
Liquidation fees	0.0019 BTC	0.0019 ETH
Contract size	1 BTC	1 ETH
Minimum order size	0.1 Option contract	1 Option contract
Minimum tick size	Option price up to 0.0050, tick size 0.0001 BTC Option price > 0.0050 tick size 0.0005 BTC	Option price up to 0.0050, tick size 0.0001 ETH Option price > 0.0050 tick size 0.0005 ETH
Minimum block size	25 BTC (options)	250 ETH (options)
Minimum block tick size	0.0001 BTC	0.0001 ETH
Minimum combo tick size	0.0001 BTC	0.0001 ETH
Position Limit	Standard margin account: Maximum total short option position size 1,000 BTC	Standard margin account: Maximum total short option position size 10,000 ETH
Trading bandwidths	Determined by the risk management and based on a risk matrix.
Mistrade correction value	0.05 BTC away from the mark price	0.05 ETH away from the mark price

Black-Scholes Formula

These are the formulas as used with Deribit's inverse (coin settled) options.

Call option price:

C = (X * N(d1)) - (K * N(d2) * e^(-R * T))

Put option:

P = (K * N(-d2) * e^(-R * T)) - (X * N(-d1))

d1 and d2 are calculated as follows:

d1 = (ln(X/K) + (R + ((σ^2)/2)) * T) / (σ * sqrt(T))

d2 = d1 - (σ * sqrt(T))

The interest rate (R) is calculated as follows:

R = ln(F/X)/T

(C/P) Option Price/Market Price	The mark price of the call/put option (or bid/ask when calculating bid/ask IV)
(X) Index	The price of the relevant Deribit index
(K) Strike Price	The strike price of the option
(F) Forward Price	Forward price for the option expiry
(R) Interest Rate	The interest rate as calculated by Deribit
(T) Time Until Expiration	The amount of time in years until the expiry of the option. Example: If an option expires in 1 day and 17 hours, the time to expiry is (1+(17/24))/365 = 0.00468 years The full amount of time is included in the calculations.
(σ) Volatility	The IV of the option. The standard deviation the underlying asset's returns.
(N) Normal Distribution	The standard cumulative normal distribution function

Order Types

Currently, only limit orders (not market orders) are accepted by the matching engine for options. Market orders are not available for options. Additionally, an order can be a “post-only” order; however, this functionality is not available for advanced order types (explained below).

A post-only order will always enter the order book without being instantly matched. If the order were to be matched, our trading engine would adjust the order so that it enters the order book at the next best possible price.

Example: If a trader places a buy order at 0.0050 BTC, but there is an offer for 0.0045 BTC, the price of the order will be automatically adjusted to 0.0044 BTC, so that it enters the order book as a limit order.

For options trading, the platform supports two additional advanced order types. The order book’s prices are in BTC and the options are priced in BTC. However, it is possible to submit volatility orders and constant USD value orders.

By filling the options order form, the trader can choose to determine the price in 3 ways: in BTC, USD, and Implied Volatility.

When an order is priced in USD or implied volatility, the Deribit engine will continuously update the order to keep the USD value and the Implied Volatility at the fixed value as entered in the order form. IV and USD orders are updated once per 6 seconds.

USD Orders

Fixed USD orders are useful when a trader has decided that he wants to pay X dollars for a certain option. Due to the changing exchange rate, this value is not constant in BTC, however, the order book works only with BTC. To maintain the constant USD value, the order will be continuously monitored and edited by the pricing engine.

For USD orders, the relevant Deribit index is used to determine the BTC price of the option.

Volatility Orders

Volatility orders are orders, with pre-set constant implied volatility. This type of order makes it possible to market-make options series without additional market maker applications.

Automatic hedging with futures is not yet supported, however, is on the roadmap. Black's option pricing model is used to determine prices. Please note that the prices of USD and Volatility orders are updated once per second. For Volatility orders it is the forward price, rather than the index, that is used as an input to the pricing model for calculating the option price.

Allowed Trading Bandwidth

Option trades are limited by combination of 2 parameters:

The highest and lowest potential values of the contract given a 1 price bucket move in the portfolio margin risk matrix, and a minimum trading bandwidth constant (currently set to 0.015).

Orders beyond the bandwidth will be adjusted to the maximum possible buy price or minimum possible sell price. This approach ensures that the trading limits reflect both the potential risk associated with the option contract and the need for market stability.

If market circumstances require so, bandwidth parameters could be adjusted at the sole discretion of Deribit.

Mistrade Rules

Due to various reasons, there can be a situation when options are traded at prices caused by an abnormal non-orderly market, with a high chance that one side of the trade has been done unwillingly. In such cases, Deribit might adjust the prices or reverse trades.

Price adjustments or reversal of options trades will be done only if the traded price of the options contract was further than mistrade correction value away from the theoretical price of the underlying options contract.

If a trader realizes that a trade has been executed at a price regarded as mispriced, he should write an email to the exchange (support@deribit.com) asking for a price adjustment as soon as possible.

The theoretical price of the option is the mark price, though it is difficult for the exchange to have the mark price exactly matching the theoretical price at all times. Therefore, in case of a disagreement about the theoretical price, this price will be determined by consulting with primary market makers on the platform. If there is any disagreement, Deribit will follow their recommendations as to what was the theoretical value of the option at the moment of the trade.

A request for a price adjustment has to be made within 2 hours after the execution of the trade. If for whatever reason the counterparty has already made a withdrawal of funds, and Deribit is not capable to retrieve enough funds from the counterparty, a price adjustment will only be made for the amount that was retrievable from the counterparty account. The insurance fund is not meant and will not be used for funding mistrades.