Why the same option’s price differs across exchanges
We take one option — BTC, 80,000 strike, December 25 expiry — and look at its prices on four exchanges in the same minute. Within one settlement currency there is nothing to earn, while between coin and USDT a gap shows. We look at where it comes from and what is left of it.
Scanners show “identical options with different prices”. Before trusting such setups, let us look at one option on all four exchanges in the same minute — and sort out what is a real difference and what is conversion. How the exchanges work is covered in lesson 3.
One option on four exchanges
| Exchange | Currency | Bid / ask | In dollars | IV bid / ask |
|---|---|---|---|---|
| Deribit | BTC | 0.0460 BTC / 0.0465 BTC | $3,555 / $3,594 | 37.2 / 37.5% |
| OKX | BTC | 0.0455 BTC / 0.0460 BTC | $3,516 / $3,555 | — |
| Binance | USDT | 3,640 USDT / 3,660 USDT | $3,640 / $3,660 | 37.5 / 37.7% |
| Bybit | USDT | 3,640 USDT / 3,670 USDT | $3,640 / $3,670 | 37.2 / 37.4% |
| Exchange | Currency | Bid / ask | In dollars | IV bid / ask |
|---|---|---|---|---|
| Deribit | BTC | 0.0725 BTC / 0.0730 BTC | $5,603 / $5,642 | 37.2 / 37.5% |
| OKX | BTC | 0.0715 BTC / 0.0725 BTC | $5,526 / $5,603 | — |
| Binance | USDT | 5,555 USDT / 5,595 USDT | $5,555 / $5,595 | 37.2 / 37.5% |
| Bybit | USDT | 5,555 USDT / 5,600 USDT | $5,555 / $5,600 | 36.9 / 37.3% |
What could be bought and sold
| Option | Buy → sell | Settlement currency | Gap |
|---|---|---|---|
| Call | Binance → Bybit | same currency | −$20 |
| Call | OKX → Deribit | same currency | $0 |
| Call | Deribit → Binance | coin ↔ USDT | +$46 |
| Call | OKX → Binance | coin ↔ USDT | +$85 |
| Put | Binance → Bybit | same currency | −$40 |
| Put | OKX → Deribit | same currency | $0 |
| Put | Binance → Deribit | coin ↔ USDT | +$8 |
| Put | Deribit → Binance | coin ↔ USDT | −$87 |
- Within one settlement currency the books do not cross: on Binance and Bybit the best call bid is the same 3,640 USDT and the ask is higher; on Deribit and OKX one exchange’s bid equals the other’s ask. This is the normal state of a liquid market: market makers keep prices consistent.
- Between coin and USDT the call on coin exchanges is cheaper once converted: buying on OKX and selling on Binance gives $85 before fees. But the put on coin exchanges is pricier in the same minute: buying on Deribit and selling on Binance gives −$87.
A cheaper call and a pricier put — what it means
If coin exchanges simply “underpriced” the option, both calls and puts would be cheaper. Here calls are cheaper and puts pricier — while IV is almost the same. That is what different conversion looks like. We converted the coin option price to dollars at spot ($77,285), while USDT options are priced from a forward: Bybit’s ticker shows an underlying price of $78,053.86, and the Deribit future for the same date was about $77,939. The gap between spot and forward is the same basis as in the futures course. A higher forward makes calls pricier and puts cheaper.
Why prices on exchanges do not match
| Cause | What changes |
|---|---|
| Settlement currency | Premium and payoff in BTC or USDT — different assets on the way to expiry |
| Forward and conversion | Coin prices converted at spot systematically differ from USDT prices |
| Index and settlement price | Each exchange has its own index; settlement prices are close but need not match |
| Contract size | 1 BTC on Deribit and Binance, 0.01 BTC on OKX; altcoin multipliers differ several-fold |
| Fees and caps | From 0.024% to 0.03% of the underlying, caps of 7–12.5% of the premium |
| Liquidity | Deribit has the deepest books; other exchanges are wider and lag |
| Margin | A short leg on one exchange does not net against a long leg on another |
Frequently asked questions
Why does the same option cost different amounts on different exchanges?
Because of different settlement currencies (coin or USDT), different dollar conversion (spot or forward), their own indices, contract size, fees and liquidity.
Can I buy an option cheaper on one exchange and sell it higher on another?
Between exchanges with the same settlement currency the books usually do not cross. Between coin and USDT options a gap shows, but it is more often conversion than a market error, and little of it survives fees.
Why is the call cheaper on Deribit but the put pricier than on Binance?
A coin price converted at spot and a USDT price derived from the forward diverge in opposite directions for calls and puts. It signals the gap between spot and forward, not underpricing.
Why look at IV?
IV does not depend on the quote currency. If the legs’ IV is almost the same, the market prices the risk the same way, and the price gap is more likely conversion.
Sources
- 1.Inverse OptionsDeribit9/26/2026official
- 2.OKX Options IntroductionOKX8/5/2026
- 3.What Is Options Trading?Binance
- 4.Binance Options Trading FeesBinance3/6/2026
- 5.FeesDeribit10/22/2026
- 6.Deribit Index Price MethodologyDeribit10/28/2026
- 7.
- 8.P2P.Army: cash-and-carry — the spot–futures basisP2P.Army10/31/2026
- 9.P2P.Army: options arbitrage scannerP2P.Army10/31/2026
About the author
Crypto expert, arbitrage trader and investor
Crypto expert and hands-on crypto arbitrage trader, investor and software developer with over 20 years of experience. On the P2P.Army blog he covers exchange news, P2P and cross-exchange arbitrage.
- Crypto arbitrage
- P2P arbitrage
- Cross-exchange arbitrage
- Crypto exchanges
- Investing
- Software development
