Options and Volatility: VIX vs UK Volatility Benchmarks
On most days, market TV flashes the VIX quote as if it were a global fear gauge. In reality, it is a very specific barometer: implied volatility on S&P 500 options over the next 30 days. London has its own equivalents – they just sit further down the screen.
The CBOE Volatility Index (VIX) measures the market’s expectation of annualised volatility in the S&P 500 over the coming month, inferred from a strip of near‑term index options. It is quoted as a percentage: a VIX at 20 implies an expected 20% annualised move in the S&P 500 over the next 30 days, and it is widely used as a proxy for US equity risk appetite. Capital.com’s primer calls it “the fear index” and notes that it reflects option prices, not realised volatility – a forward-looking, options-implied view.
For UK equities, the closest analogue is the FTSE 100 Implied Volatility Index, often shown as VFTSE. FTSE Russell’s own description of the FTSE Implied Volatility Index Series (IVI) explains that it provides end-of-day implied volatility estimates for the FTSE 100 and FTSE MIB at 30, 60, 90, 180 and (for FTSE 100) 360-day horizons, derived from index-option prices. Like VIX, the FTSE IVI is forward‑looking and designed as “an indicator of market sentiment and volatility", giving traders and risk managers a concise way to track how much movement is priced into FTSE 100 options.
Recent data suggest that UK implied volatility has been running below US levels. Historical tables for the FTSE 100 VIX (VFTSE) show readings clustered in the 10–13 range for much of the latest period, with occasional spikes above 15; one snapshot puts the index at 10.96. By contrast, IG’s live VIX quote in early 2026 shows the US fear gauge around 19–20, with intraday highs near 19.4 and lows just above 19. That gap reflects both higher global attention on US events and the more growth‑ and tech‑heavy composition of the S&P 500 compared with the value‑tilted, income‑oriented FTSE 100.
For investors, the key distinction is that VIX and VFTSE are local measures. VIX is driven by US macro data, Fed expectations and AI-heavy sector risk; UK implied vol depends more on UK- and Europe-specific news, sterling moves and the commodity/bank mix inside the FTSE. In a global portfolio, they serve as complementary tools: VIX tells you how jumpy US index‑option traders are; VFTSE and the FTSE IVI series show how much movement is priced into UK blue chips. Neither is a perfect proxy for “global fear", but together they map where options markets see the next shock coming from – Wall Street or the City.