How do you trade volatility directly? I keep hearing about straddles and the 'vol surface' but need clarity.

Volatility trading means profiting from changes in implied volatility or from realized volatility differing from what the market expects — regardless of which direction the underlying moves.

Core Strategies:

1. Long Straddle (Long Vol):

Buy an ATM call and ATM put with the same strike and expiry. You profit if the stock makes a large move in either direction.

• Cost: Premium of both options (expensive)
• Breakeven: Strike plus/minus total premium paid
• Profit driver: Realized vol > implied vol at entry

2. Long Strangle (Long Vol, Cheaper):

Buy an OTM call and OTM put. Cheaper than a straddle but requires a larger move to profit.

• Lower cost, wider breakeven range
• Popular pre-earnings when you expect a big move but can't predict direction

3. Short Straddle/Strangle (Short Vol):

Sell instead of buy. You collect premium and profit if the stock stays range-bound.

• Maximum profit: Total premium received
• Risk: Unlimited if stock moves sharply

The Volatility Surface:

Implied volatility isn't constant across strikes and expirations — it forms a 3D surface:

Equity Volatility Skew:

In equity markets, OTM puts consistently have higher implied volatility than OTM calls. This 'skew' reflects:

• Demand for downside protection (portfolio insurance)
• Fat left tails — crashes are more common than equivalent rallies
• Leverage effect — falling prices increase firm leverage, increasing volatility

Trading the Skew:

• Risk reversal: Sell an OTM put and buy an OTM call (or vice versa). Expresses a view on skew richness.
• Butterfly spread: Buy 1 low strike call, sell 2 ATM calls, buy 1 high strike call. Profits if skew is mispriced.

Practical Example:

Caspian Capital believes the market is underpricing near-term volatility ahead of a central bank decision. They buy a 2-week ATM straddle on the S&P 500 index at 22% implied vol. If realized vol over those 2 weeks turns out to be 28%, the straddle profits — the stock moved more than the options priced in.

Conversely, if the decision is a non-event and realized vol is only 15%, the straddle loses money from time decay exceeding any directional gains.

Dive deeper into volatility strategies in our CFA Level II Derivatives course.