Term Structure
The term structure of volatility is how implied volatility changes across expirations. Learn what contango and backwardation mean and how traders read the curve.
The term structure of volatility is how implied volatility changes as you look further out in time. Near-term options might price in one level of expected movement, while options months away price in another. Plot IV against expiration date and you get the term-structure curve.
It is the time axis of volatility, the companion to skew's strike axis. Together they make up the whole volatility surface. Let me show you how to read the curve.
The Near and Far Forecast
Think of two weather forecasts: one for tomorrow and one for a month from now. They can disagree, and so can the market's volatility forecast for next week versus next quarter.
Usually the curve slopes gently upward. Longer-dated options carry slightly higher implied volatility, because more time means more room for the unexpected, so the distant future is priced as a touch more uncertain than the calm near term. This normal, upward-sloping shape is called contango.
But the curve can flip. When a near-term shock looms, an earnings report, a Fed meeting, a crisis, the front-month IV spikes above the longer-dated IV, and the curve slopes downward. That inverted shape is called backwardation, and it is the market shouting that the immediate future looks scarier than the distance.
Reading the Curve
The shape of the term structure is a live read on market conditions, and traders use it constantly.
Contango, the calm norm. When things are quiet, the upward slope is gentle and orderly. This is the backdrop for most ordinary trading, and it means near-term options are relatively cheap compared with longer-dated ones.
Backwardation, the stress signal. When the front month spikes above the back months, fear is concentrated right now. During a crash or ahead of a major event, the term structure inverts, and a steep inversion is a hallmark of a market in stress.
The slope also guides time-based trades. A calendar spread sells near-term volatility and buys longer-term, so it leans on the term structure: it tends to work best when near-term IV is elevated relative to the back months, as it often is in backwardation.
Why It Matters
The term structure stops you from treating "the IV" as one number. A stock does not have a single implied volatility, it has a whole curve of them across time, and the shape carries information.
Read it and you learn whether the market's anxiety is immediate or long-run, whether near-term options are rich or cheap versus later ones, and which expiration to pick for a given trade. Paired with skew, the strike-by-strike lean, the term structure completes the picture of how volatility is priced.
- Term structure is how implied volatility varies across expirations.
- Contango is the normal upward slope: longer-dated IV higher.
- Backwardation is an inverted curve: near-term IV spikes, a stress signal.
- It is the time axis of the volatility surface, paired with skew.
Pop Quiz
Three quick questions to see what stuck. Pick an answer and the explanation shows up right away.
What does the volatility term structure show?
Term structure is the time axis: IV plotted against expiration date, from near-term to far.
What is backwardation in the term structure?
Backwardation is the inverted shape, near-term IV spiking above the back months, a sign of near-term stress.
Which trade leans directly on the term structure?
A calendar spread trades near-term against longer-term volatility, so the term-structure slope drives it.
Bottom Line
The term structure is the market's volatility forecast stretched across time. Normally it slopes gently up in contango, calm near term and slightly more uncertain far out. When a shock looms, it flips into backwardation, near-term fear spiking above the distance.
Read the slope and you know whether anxiety is immediate or long-run, which options are relatively cheap, and how time-based trades like calendars are likely to behave. It is the time axis that, together with skew, completes the volatility picture.
Keep going: the strike axis is skew, the full map is the volatility surface, and the trade that rides the curve is the calendar spread.