What the Volatility Risk Premium Is
The volatility risk premium (VRP) is the persistent gap between the volatility the options market prices in and the volatility that actually shows up afterward. Put simply:
The definition
VRP = implied volatility − subsequently realized volatility
Implied volatility is forward-looking and observed today (the VIX is the headline measure for the S&P 500). Realized volatility is backward-looking and only knowable after the fact, computed from the actual day-to-day moves of the index over the same horizon.
On average, the VIX overstates the volatility the S&P 500 goes on to realize. In other words, 30-day implied volatility tends to sit above the volatility the index actually delivers over the following 30 days. That positive gap is the premium. It is one of the most studied and most reliable features of equity-index option markets, and it is the economic engine behind nearly every short-volatility strategy.
This relationship is closely connected to the difference between forward-looking and historical measures of risk. If you have not yet read it, our guide to implied versus historical volatility covers the two inputs that define the premium.
How big is it?
On the S&P 500, 30-day implied volatility has historically averaged roughly 3 to 4 volatility points above subsequently realized volatility. The exact figure depends on the sample period and the realized-volatility estimator used, so treat it as an order of magnitude rather than a fixed constant. The gap compresses toward 1 to 2 points during calm, low-volatility regimes and turns sharply negative during crashes, when realized volatility blows past whatever was priced in beforehand.
| Regime | Typical implied − realized gap | Who tends to profit |
|---|---|---|
| Calm, trending market | +1 to +2 points | Volatility sellers |
| Normal conditions (long-run) | +3 to +4 points (average) | Volatility sellers |
| Volatility spike / crash | Deeply negative | Volatility buyers |
Why the Premium Exists
The VRP is not an inefficiency to be arbitraged away — it is a risk premium, compensation paid to whoever is willing to bear volatility risk. Several reinforcing forces keep it positive:
- Insurance demand. Index options, especially out-of-the-money puts, function as portfolio insurance. Investors are structurally willing to pay more than the actuarially fair price for downside protection, just as homeowners overpay for fire insurance relative to expected losses. That overpayment is the premium the option seller collects.
- Risk aversion and crash fear. Losses during a market crash hurt most precisely when capital is scarcest. Investors will pay up to hedge that state of the world, pushing implied volatility above the statistically expected level. This is tightly linked to the volatility skew — the reason OTM puts trade richer than OTM calls.
- Supply/demand imbalance. There are many natural buyers of downside protection (pension funds, asset managers, structured-product desks) and comparatively few natural sellers. The price of volatility clears above its expected realized value to draw enough sellers into the market.
- Negative correlation with equities. Volatility spikes when stocks fall. An asset that pays off in bad states is valuable, so investors accept a negative expected return to hold it — which is the same as saying sellers earn a positive expected return. See VIX and S&P 500 correlation for why this inverse link is so strong.
Relationship to Contango
The VRP and futures-curve contango are cousins, not twins. The VRP is measured on options (implied vs. realized). Contango is the upward slope of the VIX futures curve, where longer-dated contracts trade above spot VIX roughly 75–80% of the time.
Both arise from the same underlying force — persistent demand for volatility protection — and both reward sellers in calm markets. When the curve is in contango, a long VIX-futures position loses value as each contract "rolls down" the curve toward the lower spot price over time. That roll-down is what erodes long-volatility exchange-traded products, and it is the mirror image of the premium that short-volatility positions collect. Our blog post on VIX futures roll yield works through the mechanics in detail.
Volatility risk premium
Implied minus realized volatility, measured on S&P 500 options. Harvested through option selling and put-writing.
Contango / roll yield
Upward VIX futures slope. Harvested through shorting front-month futures or holding short-vol products.
How the Premium Is Harvested
If implied volatility is usually richer than what realizes, sellers of volatility should, on average, win. The common ways to express that view:
- Put-writing. Systematically selling cash-secured S&P 500 puts (the approach tracked by indices such as Cboe's PUT index) collects option premium that, on average, exceeds the losses paid out on the puts.
- Short straddles and strangles. Selling both a call and a put captures premium when realized movement comes in below the implied move the options were priced for.
- VIX futures roll-down. Shorting front-month VIX futures in contango aims to capture the decline as the contract converges toward a typically lower spot. See our overview of how to short volatility for the instruments involved.
- Inverse and short-vol ETPs. Products designed to deliver the inverse of short-term VIX futures returns mechanically harvest roll-down in calm markets.
This is educational information, not investment advice. Short-volatility strategies carry uncapped or severe downside risk and are not appropriate for every investor.
Why It Is Not Free Money
The single most important thing to understand about the VRP is that it is not an arbitrage. It is payment for accepting a deeply unattractive payoff shape:
- Negative skew. Short-volatility returns look like "picking up nickels in front of a steamroller" — a long string of small, steady gains interrupted by sudden, outsized losses. The average return is positive only because it embeds the expectation of those rare large drawdowns.
- Crash risk and tail exposure. When volatility spikes, the premium inverts violently. A position that earned a few points a month for years can give back several years of gains in days.
- Leverage and liquidity fragility. The risk compounds when leverage is involved.
Volmageddon, 5 February 2018
The S&P 500 fell about 4.1% — its largest one-day drop since 2011 — and the VIX recorded its largest-ever single-day percentage jump, roughly +115%, closing near 37.32 from about 17.31 the prior day. The surge detonated heavily-shorted inverse-VIX products; the best-known inverse ETN lost the vast majority of its value and was subsequently terminated. Years of accumulated premium were erased in a single afternoon.
The episode is the canonical case study in why VRP harvesting demands strict position sizing and an understanding of tail risk. Many of the products that imploded were levered or designed without a floor on losses. The premium was real; the way it was being collected was not survivable.
Watching the Premium in Practice
Traders gauge whether the premium is rich or thin by comparing the VIX (30-day implied) against recent realized S&P 500 volatility, and by watching second-order measures. The VVIX — the volatility of the VIX itself — signals how expensive VIX options are and how nervous the market is about volatility spiking; our comparison of VIX vs. VVIX explains the relationship. The shape of the term structure tells you whether the curve is paying sellers (contango) or punishing them (backwardation). A wide implied-to-realized gap with a steep contango is the "fat premium" environment short sellers prefer; a collapsing or inverted curve is the warning that the premium is about to be paid out to buyers.
Frequently Asked Questions
Is the volatility risk premium always positive?
No. The premium is positive on average and most of the time, but it inverts sharply during volatility spikes, when realized volatility overshoots the implied volatility that was priced in beforehand. The long-run average is positive precisely because sellers must be compensated for those losing episodes.
How large is the volatility risk premium?
On the S&P 500, 30-day implied volatility has historically averaged roughly 3 to 4 volatility points above subsequently realized volatility, though the gap narrows toward 1 to 2 points in calm regimes and turns deeply negative during crashes. The exact figure depends on the sample window and how realized volatility is measured.
Is harvesting the volatility risk premium free money?
No. Short-volatility returns have a negatively skewed payoff: many small gains punctuated by occasional large losses. The February 2018 Volmageddon event wiped out inverse-VIX products in a single session, illustrating that the premium is compensation for bearing crash risk, not an arbitrage.
How does the volatility risk premium relate to contango?
They are related but distinct. The volatility risk premium is the implied-minus-realized gap on options. Contango is the upward slope of the VIX futures curve. Both reflect demand for volatility protection, and both tend to reward sellers in calm markets, but they are measured on different instruments.