The S&P 500 has been the default passive bet for four decades. It’s concentrated, market-cap weighted, and 100% American — which is fine until it isn’t. If you’re looking for something more diversified, more factor-aware, or simply more yours, there are eight credible routes.
Why look past the S&P 500 at all?
The index that beat active managers for a generation has genuine structural risks most investors under-price:
- Extreme concentration.As of early 2026 the top ten names account for roughly 35% of the index. Five of those are tightly correlated mega-cap tech. You can buy “500 companies” and end up with a leveraged bet on seven.
- No international exposure.The US is ~60% of global market cap and <5% of global population. A truly passive allocation would own the rest of the world too.
- Cap-weighting buys high.The rule mechanically allocates more capital to stocks whose prices have already risen. That’s fine in a trending market and painful in a regime change.
- No factor tilts. Decades of academic work on value, size, quality, and momentum suggest premium returns from deliberate tilts. A cap-weighted index gives you none of them by construction.
1. Equal-weight S&P 500 (RSP)
Same 500 companies — each held at 0.2%. Invesco’s RSP is the benchmark implementation. Removes concentration risk at a stroke and gives small-caps and value names a larger voice.
What it’s good for
- Diversification inside the same universe you already trust.
- Historically higher returns during value-led regimes (2000–2007, 2022).
- Automatic “sell high, buy low” at each rebalance.
What it’s bad for
- Higher turnover → worse tax efficiency in a taxable account.
- Slight lag in extended mega-cap rallies (late 2010s, 2023).
- Slightly higher fees (0.2% vs 0.03% for SPY).
2. Nasdaq-100 (QQQ / QQQM)
The 100 largest non-financial Nasdaq listings. Not an “alternative” in the diversification sense so much as a different bet — a bigger helping of the growth, tech, and consumer-discretionary names that have driven the last decade.
3. Total US market (VTI / SCHB / ITOT)
Vanguard’s VTI owns ~3,800 US stocks — the S&P 500 plus the mid-caps and small-caps the index drops. Academically the cleanest “own the US equity risk premium” bet.
Returns track the S&P 500 closely (small and mid caps are only ~15% of total market cap) but diversification is genuinely better. If you were going to pick a single ETF and stop, this is a more defensible choice than SPY.
4. Quality-factor tilts (QUAL, MOAT)
Quality is the most persistent equity factor in the peer-reviewed literature: companies with high return on equity, stable earnings, and low leverage tend to outperform over long horizons with lower drawdowns.
- MSCI QUAL (iShares, 0.15%) — rules-based screen on ROE, earnings variability, debt-to-equity.
- VanEck MOAT(0.46%) — Morningstar’s discretionary pick of 40 wide-moat names. More expensive, more concentrated, more opinionated.
5. Global ex-US (VXUS / IXUS)
A home-country bias costs unsuspecting investors roughly 40% of the planet’s market cap. Pairing an S&P 500 holding with ~30% VXUS gets you closer to a truly global portfolio — and historically reduces volatility without sacrificing long-run returns.
6. Small-cap value (AVUV)
Avantis’ AVUV is the cleanest available implementation of the “size + value + profitability” three-factor model. Higher expected returns, genuinely orthogonal to the S&P 500, brutal drawdowns during risk-off episodes. A textbook diversifier: the correlation with SPY is ~0.7, not 0.98.
7. A custom, direct-indexed basket
Direct indexing — owning the underlying stocks yourself rather than the ETF wrapper — was a private-bank product with a $10m minimum until about 2022. With fractional shares and zero commissions it’s now accessible to any retail account.
The trade-off: you give up the operational simplicity of one ticker in exchange for:
- Tax-loss harvesting on individual names, not the aggregate fund.
- Custom exclusions— drop your employer’s stock, drop tobacco, drop whatever you want.
- Custom tilts— “S&P 500 but overweight energy, underweight banks” is a five-minute decision, not a fund launch.
This is what Arithmos does. You describe the exposure in English, the agent picks the names and weights, and you export the resulting list to your broker — or fire the trades through the built-in broker integration.
Side-by-side comparison
| Fund | Ticker | Expense | 10Y CAGR | Volatility | Correlation to S&P 500 |
|---|---|---|---|---|---|
| S&P 500 | SPY | 0.09% | ~12.8% | ~15% | 1.00 |
| S&P 500 equal-weight | RSP | 0.20% | ~11.2% | ~16% | 0.94 |
| Nasdaq-100 | QQQ | 0.20% | ~17.1% | ~19% | 0.95 |
| Total US market | VTI | 0.03% | ~12.4% | ~16% | 0.99 |
| Quality factor | QUAL | 0.15% | ~11.8% | ~14% | 0.97 |
| World ex-US | VXUS | 0.07% | ~5.2% | ~15% | 0.86 |
| Small-cap value | AVUV | 0.25% | ~9.6% (since 2019) | ~22% | 0.72 |
| Custom direct-indexed | — (your basket) | 0 mgmt fee | depends on rules | depends | depends |
How to actually choose
Ignore the “best index fund” listicles that rank on trailing one-year returns. The right question is what purpose the fund serves in your portfolio. In order:
- Work out your anchor.For most investors that should be a broad-market core — VTI or the S&P 500 — at 50–100% of equity allocation.
- Decide if you want diversification or a tilt.Diversifiers reduce risk (VXUS, AVUV). Tilts amplify it (QQQ, MOAT). Conflating the two is how portfolios end up with 15 funds and one exposure.
- Pick the cheapest clean implementation.Once you’ve chosen the exposure, the difference between a 0.03% fund and a 0.50% fund compounds to thousands of pounds over a decade. Cheaper almost always wins.
- Consider going direct.If your taxable account is large enough that tax-loss harvesting matters (£50k+), or you have conviction on specific exclusions or tilts, direct indexing is now the institutional-grade move that the ETF wrapper can’t replicate.
FAQ
Is the S&P 500 still a good investment in 2026?
For a low-cost, low-effort core equity holding: yes. It’s transparent, cheap, and captures the US equity risk premium. The critique isn’t that it’s bad— it’s that for many investors it’s not complete.
What’s the safest alternative?
“Safer” depends on which risk. For concentration risk: RSP (equal-weight). For single-country risk: add VXUS. For sequence-of-returns risk near retirement: pair equities with short-duration Treasuries — that’s an asset-allocation question, not an index-choice one.
What beats the S&P 500 long-term?
Over any 10-year window you can reliably find somethingthat beat it — small-cap value in the 2000s, quality in the 2010s, tech in the 2020s. No credible model predicts which factor outperforms over the next decade. The evidence supports diversifying across factorsrather than picking this year’s winner.
Can I build a custom S&P 500 alternative myself?
Yes — and it takes about thirty seconds. Open the builder and type “S&P 500 but equal-weighted, excluding tobacco and fossil fuels, rebalanced quarterly”. Arithmos will assemble the holdings, run a 10-year backtest against SPY, and hand you a downloadable basket or a one-click export to your broker.