Nasdaq 100 (USTEC) vs S&P 500: Which Index Fits Your Volatility Tolerance?

Traders often pick between the Nasdaq-100 and the S&P 500 on reputation: one is "the tech index", the other is "the market". The more useful question is how much each one moves, why, and what that means for the size of your positions and the losses you can live with. This guide compares the two indices on composition, measured volatility and practical risk, using the index provider's own published data.

What is the difference between the Nasdaq-100 and the S&P 500?

The Nasdaq-100 includes 100 of the largest domestic and international non-financial companies listed on the Nasdaq Stock Market, ranked by market capitalisation, and it contains no financial companies (Nasdaq Global Indexes). The S&P 500 tracks around 500 large US companies across every sector, including banks and insurers, regardless of which exchange they list on.

Many CFD brokers label these markets differently. The Nasdaq-100 is often called USTEC, NAS100 or US100, and the S&P 500 is often US500 or SPX500. These are derivatives that track the index; they are not the index itself, and each provider sets its own spreads, hours and contract sizes.

In plain words, volatility is how much prices swing around their average. It is usually reported as an annualised standard deviation of returns: a higher number means wider and more frequent swings in both directions.

How much more volatile is the Nasdaq-100 than the S&P 500?

Somewhat more, not dramatically more. Nasdaq's comparison of the two indices for the 18 years from 31 December 2007 to 31 December 2025 reports annualised volatility of 22.9% for the Nasdaq-100 against 20.1% for the S&P 500. Over the same period, Nasdaq says the one-year rolling volatility of the Nasdaq-100 was on average 2.9% higher, and the correlation of daily returns between the two indices was 93% (Nasdaq Global Indexes, Q4 2025 edition).

That high correlation matters. On most days the two indices move in the same direction; the Nasdaq-100 simply tends to move further. Averages also hide regimes. In calm markets the gap can be small, while in sell-offs led by technology shares it can widen sharply. Treat long-run averages as a baseline, not a forecast.

Why does the Nasdaq-100 swing harder?

The short answer is concentration. As at 31 December 2025, technology made up about 63% of the Nasdaq-100 by Nasdaq's industry classification, compared with about 41% of the S&P 500. The S&P 500 also carries around 11% in financials, a sector the Nasdaq-100 excludes by design (Nasdaq Global Indexes, Q4 2025 edition).

When a large share of an index sits in one sector, news that hits that sector, such as interest rate expectations for growth companies or earnings from the largest technology firms, moves the whole index more. A broader mix of sectors gives the S&P 500 more internal offsets, although in a broad market shock almost everything falls together.

Figures are from Nasdaq Global Indexes and ASIC. Cboe publishes the VIX for the S&P 500 and the VXN for the Nasdaq-100 as measures of expected volatility implied by options prices.

What does the volatility gap mean for position size?

If you risk the same dollar amount on each trade and set stops relative to how much a market normally moves, the more volatile index needs a smaller position. Here is illustrative arithmetic using the long-run figures above, not a forecast.

• Annualised volatility divided by the square root of roughly 252 trading days gives a rough daily figure: about 1.44% for the Nasdaq-100 and about 1.27% for the S&P 500.
• Suppose a trader places stops at 1.5 times that typical daily move: about 2.2% away on the Nasdaq-100 and 1.9% on the S&P 500.
• With a fixed $200 risk per trade, the position can be worth about $9,260 of Nasdaq-100 exposure or about $10,530 of S&P 500 exposure.

So, on these averages, matching risk means holding roughly 12% less exposure in the Nasdaq-100. Traders who use the same size on both, or who copy a stop distance from one index to the other, end up taking more risk on the Nasdaq-100 without deciding to. The full sizing method is in the 1% rule for position sizing.

Which index fits which volatility tolerance?

Neither index is "safer" in any absolute sense, and this is general information rather than a recommendation. The differences tend to show up like this:

• Lower tolerance for swings: the S&P 500's broader mix usually produces somewhat smaller moves, which can make stop placement and sizing more forgiving.
• Higher tolerance for swings: the Nasdaq-100's larger ranges can suit traders who deliberately size smaller and accept being stopped out more often in noisy conditions.
• Short-term traders at the open: both indices are most volatile early in the session, so the open magnifies whatever gap already exists. See scalping the US500 at the open for how that plays out.
• Prop firm challenges: daily loss limits can be hit faster on the more volatile index if size is not adjusted; prop firm challenge rules explains why.

How do you compare the two indices against your own risk limits?

1. Fix your maximum loss per trade in dollars before looking at charts.
2. Measure the typical range of each market on the timeframe you trade, for example the average true range over the last 20 sessions on your platform.
3. Set stop distances from that range, not from a number of points copied across markets.
4. Calculate position size as your dollar risk divided by the stop distance in dollars per point.
5. Check costs as a share of the range. Compare each provider's spread with the typical move; a spread that is small on one index can be large relative to your target.
6. Check margin and currency. Confirm the margin required at 20:1 and remember that profits and losses on US index CFDs are in US dollars, so an Australian-dollar account also carries currency risk.
7. Journal the results separately for each index so you can see where your rules actually hold up. Trading journal data points lists what to record.

Does higher volatility mean higher returns?

Not reliably. Nasdaq reports an annualised total return of 16.0% for the Nasdaq-100 against 11.0% for the S&P 500 from the end of 2007 to the end of 2025 (Nasdaq Global Indexes, Q4 2025 edition). That is a description of one historical period, published by the index provider, and past performance is not a reliable indicator of future performance. Higher volatility also means deeper falls along the way, and for a leveraged short-term trader the path matters more than the long-run average.

What are the risks of trading index CFDs in Australia?

Leverage magnifies losses. Since 29 March 2021, ASIC's product intervention order has limited retail leverage on CFDs over major stock market indices, which include both the Nasdaq-100 and the S&P 500, to 20:1. It also standardised margin close-outs and requires negative balance protection, so retail losses are limited to the funds in the CFD account (ASIC, 2020). ASIC extended the order to 23 May 2027 (ASIC, 2022).

Most retail CFD traders have lost money. ASIC's 2017 review found 72% of clients trading CFDs lost money (ASIC, 2019), and even after the leverage limits took effect, half of retail CFD accounts were loss-making in the order's first three months (ASIC, 2021). Choosing the calmer index does not change those odds on its own; sizing, costs and discipline do. Why day traders fail explains how leverage turns ordinary swings into account-ending losses.