The volatility smile: why crypto options' wings cost more

If the model behind implied volatility were the whole truth, every option on one expiry would show the same volatility, whatever its strike. They don't. Drawn strike by strike, volatility is lowest near the money and rises towards both ends, the wings: a curve called the volatility smile. It's seldom even, and which wing is higher, the skew, says what traders are paying most to be covered for.

What is the volatility smile?

Take every option on one expiry, write each one's price as its implied volatility (implied volatility explained), and draw them by strike: puts below the forward and calls above it, the options out of the money on each side, which trade the most. A flat line would mean the market prices every strike from one volatility. The smile says it doesn't: options far from the money cost more than that one volatility would make them.

"Cost more" here means in volatility. In money, an option far out of the money is cheap, as it's unlikely to pay anything; it's just dearer than the simplest model would make it, which is what its higher volatility says.

Why the wings cost more

• Big moves come more often than the model allows. The model behind implied volatility draws moves on a bell curve, where a fall of a third in a month is all but impossible at the volatilities bitcoin often trades at. Bitcoin has had several. Options that pay out in moves like those are priced up to match.
• Demand for protection. Holders of a coin buy puts to cover a fall, and pay up for them; on the other side, calls are bought for a rally, a lot of upside for a little money.
• The risk of a gap. Whoever sells an option far from the money takes a small, steady income against a rare, large loss, and a price that jumps can't be hedged on the way. They charge for it.

Skew: which wing is dearer

Stock index options nearly always have a put skew: the downside dearer, as investors pay to protect what they own. Crypto's skew can turn: in a strong rally, calls can carry the higher volatility; in a fall, puts. A put skew, strike by strike, with the forward at 100, puts below it and calls above:

Example figures, not market data.

That shape is what bitcoin's options showed on 14 October 2026: its 30 October expiry on Deribit by Coinbase was marked at 57.7% at the 66,000 strike, 21% below the forward, against 38.3% at 102,000, 22% above it, and 33.7% at 84,000, near the money. The three exchanges agreed within 0.2 points at 84,000, and less closely in the wings, up to 3.5 points apart at 102,000, where fewer options trade and each exchange's mark is more its own.

How to read the smile on the site

1. Open a coin's page, Bitcoin's or Ethereum's, and go to Volatility by strike, under the chain.
2. Each exchange is a line of its marks, puts below the forward and calls above it, the forward dashed. Hover a strike to read each exchange's.
3. Choose another expiry in the chain above it, and the smile follows. The nearer the expiry, the steeper its smile tends to be.
4. For the bids and asks behind the marks, read the chain strike by strike (how to read an option chain).

What the smile leaves out

• Marks aren't trades. Each exchange's mark is its own fair price, between its bid and its ask, and far from the money those can be wide apart.
• Other expiries. Each expiry has its own smile; side by side, they make a surface.
• Why. A steep skew says traders are paying for protection, not that a fall is coming.

Not financial advice. Prices move while you read them.