Same 500 companies, opposite weighting. Since 2003 the two approaches ended up almost even, but by very different paths. Here is what equal weight costs a retirement saver, how it behaved in the long and short run, and who it actually fits.
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If you want one low-cost US stock core, VOO fits that job better; RSP is worth considering only if you specifically want less dependence on the largest companies and accept a higher fee and long stretches of lagging. Neither weighting has won consistently, so this is a choice about what you want to own, not about which one will return more.
Scope: RSP and VOO as US large-cap stock holdings in a retirement account. Excluded: total-market funds (see VOO vs VTI), the choice among cap-weighted S&P 500 funds (VOO vs IVV vs SPY vs SPYM) and factor funds. The general mechanics of equal weighting are in equal weight vs cap weight. Education, not advice for your situation.
| If this describes you | VOO | RSP |
|---|---|---|
| You want the lowest-cost core and the market’s own weights | Fits | Costs 0.17 points more a year |
| You worry that a few giants dominate your savings | Top 10 ≈ 41% | Top 10 ≈ 3% |
| Your 401(k) already holds an S&P 500 fund | More of the same | Can offset concentration in an IRA |
| You want a lower-risk stock fund | Neither is | Fell more in 2008 and 2020 |
| You might give up after years of lagging | Lower regret risk | Lagged by about 4 points a year since 2017 |
Fees, turnover, index rules, holdings counts and trailing NAV returns (to Sep 30, 2026) from the issuers; VOO top-10 and technology weights from Vanguard (Sep 30, 2026); RSP weights from Exent market data (Oct 20, 2026); drawdowns and yields from Exent market data.
| RSP | VOO | |
|---|---|---|
| Index | S&P 500 Equal Weight Index | S&P 500 Index |
| Weighting | Same weight per company at each quarterly rebalance | By float-adjusted market value |
| Expense ratio | 0.20% | 0.03% |
| Portfolio turnover, last fiscal year | 27% | 2.4% |
| Holdings | 505 | 505 |
| Top 10 holdings, share of fund | 2.7% | 40.6% |
| Information technology | 18.0% | 39.7% (Vanguard, GICS) |
| Industrials | 15.2% | 8.0% (Vanguard, GICS) |
| 1-year / 3-year return, per year | 11.38% / 15.49% | 15.70% / 22.85% |
| 5-year / 10-year return, per year | 8.56% / 11.43% | 13.75% / 15.29% |
| Largest drop, 5 years to Sep 30, 2026 (daily) | −21.4% | −24.5% |
| Beta vs S&P 500, 60 months (Exent calculation) | 0.92 | 1.00 |
| Distribution yield, trailing 12 months (to Sep 30) | 1.53% | 1.06% |
Invesco’s prospectus describes the index as all S&P 500 components, each assigned “the same weight at each quarterly rebalance”; on Jun 30, 2026 they ranged from $5.2 billion to $4.8 trillion in market value (Invesco). Giving a $5 billion company the same weight as a $4.8 trillion one is the whole strategy: RSP behaves more like a mid-cap and value-leaning fund than the S&P 500 most people picture.
Over RSP’s full life, almost exactly not. From its first trading day in May 2003 to Sep 30, 2026, $10,000 grew to about $122,900 in RSP and $127,200 in SPY, the oldest S&P 500 ETF (VOO only launched in 2010). Split the period in two and the picture changes completely (Exent calculation on daily dividend-adjusted closes):
| Period | RSP, per year | S&P 500 (SPY), per year | Leader |
|---|---|---|---|
| May 2003 – Dec 2016 | 11.3% | 8.9% | Equal weight by 2.4 points |
| Jan 2017 – Sep 2026 | 11.3% | 15.2% | Cap weight by 3.9 points |
| May 2003 – Sep 2026 (whole life) | 11.3% | 11.5% | About even |
RSP compounded at a steady 11.3% in both halves; the cap-weighted index swung from 8.9% to 15.2% as the largest companies went from lagging to leading. Anyone choosing between them in 2016 based on the previous 13 years would have picked the fund that then trailed for almost a decade. That is the core lesson for a retirement holder: which weighting wins depends on the start date, and nobody knows the next one.
Each quarter RSP sells some of the companies that rose and buys more of those that fell, to put every company back to the same weight. That is a built-in “buy low, sell high” discipline, and it is why the fund’s turnover (27%) is about eleven times VOO’s (2.4%). It also explains the pattern above: the reset paid off when many mid-sized companies caught up (2003–2016) and cost money when a handful of giants kept compounding (2017–2026), because RSP kept trimming them.
Turnover has costs that the 0.20% fee does not show: trading spreads, and in a regular fund, taxable gains. ETFs can often avoid distributing those gains because they hand appreciated shares to market makers in-kind rather than selling them (Morningstar), but higher turnover still leaves less room than a fund that barely trades. In an IRA or 401(k), that tax point does not apply.
Sometimes, but not reliably. Equal weight helped when the largest companies led the fall and hurt when smaller companies were hit hardest. Peak-to-trough on daily total-return levels (Exent market data; recovery dates are an Exent calculation on daily dividend-adjusted closes):
| Selloff | RSP | S&P 500 | Back to the old peak |
|---|---|---|---|
| Financial crisis, Oct 9, 2007 → Mar 9, 2009 | −59.2% | −55.2% (SPY) | RSP Jan 2011; SPY Aug 2012 |
| COVID crash, Feb 19 → Mar 23, 2020 | −39.0% | −34.0% (VOO) | SPY Aug 2020; RSP Nov 2020 |
| Inflation bear market, Jan 3 → Oct 12, 2022 | −21.4% | −24.5% (SPY) | SPY Dec 2023; RSP Jan 2024 |
RSP fell further in two of three big selloffs, then recovered faster from 2009. Its five-year volatility (16.2%, Exent calculation from month-end closes) was close to the S&P 500’s, so it diversifies away from a few companies, not away from stock-market risk.
A partial blend dilutes concentration at a modest cost. Exent calculation, illustrative, on a $250,000 US stock allocation using the weights and fees above (blend value = 0.8 × VOO figure + 0.2 × RSP figure):
| Mix | Yearly fund cost | Top 10 share | Technology share |
|---|---|---|---|
| 100% VOO | $75 (0.03%) | 40.6% | 39.7% |
| 80% VOO / 20% RSP | $160 (0.064%) | 33.0% | 35.4% |
| 50% VOO / 50% RSP | $288 (0.115%) | 21.7% | 28.9% |
| 100% RSP | $500 (0.20%) | 2.7% | 18.0% |
The 80/20 blend cuts the top-10 share by about 8 points (0.8 × 40.6 + 0.2 × 2.7 = 33.0%) for $85 a year more. Whether that is worth it depends on how much large-cap technology you hold elsewhere; check whether you have too much tech exposure and how concentrated the S&P 500 is first. A blend also needs rebalancing, or it drifts back toward the winner.
| Fund | Pros | Cons |
|---|---|---|
| RSP | Every company reset to about 0.2% each quarter; more weight in industrials, healthcare and mid-sized firms; built-in rebalancing discipline; led the S&P 500 from 2003 to 2016. | 0.20% fee, about seven times VOO; 27% turnover; trailed by 3.9 points a year from 2017 to Sep 2026; fell more than the S&P 500 in 2008 and 2020. |
| VOO | 0.03% fee; 2.4% turnover; owns companies in proportion to their market value, so no bet against the market’s weights; 10-year NAV return 0.04 points a year below its index (15.29% vs 15.33%, Vanguard). | Top 10 at about 41% and information technology at about 40%, so results lean on a few giants; the S&P 500 (SPY) trailed RSP by 2.4 points a year from 2003 to 2016. |
Other ways to lean away from the largest companies; expense ratios and holdings from Vanguard, Sep 30, 2026:
| ETF | What it holds | Expense ratio | Holdings | How it reduces concentration |
|---|---|---|---|---|
| VTI (Vanguard) | Whole US market | 0.03% | 3,519 | Slightly: adds about 3,000 smaller companies |
| VXF (Vanguard) | US market minus the S&P 500 | 0.05% | 3,359 | Pairs with VOO to add mid and small caps |
| VO (Vanguard) | US mid caps | 0.03% | 271 | A direct mid-cap sleeve |
| VTV (Vanguard) | US large-cap value | 0.03% | 298 | Leans away from growth giants |
| VXUS (Vanguard) | Stocks outside the US | 0.05% | 8,901 | Diversifies by country, top 10 ≈ 14% |
When it is chosen as the “safer” S&P 500, or when you would abandon it after a bad stretch. Counterexample: someone who moved a retirement account from VOO to RSP at the start of 2017 to avoid big-tech risk earned 11.3% a year instead of about 15.2% through Sep 2026, and in the 2020 crash fell 39.0% instead of 34.0%. Switching back after years of lagging would have meant missing any reversal, and the first half of RSP’s history shows reversals happen.
It is also the wrong fix for a retiree whose real risk is too much in stocks overall: replacing VOO with RSP leaves a 100% stock portfolio exposed to a 40% to 60% fall. That question is about bonds and cash; see how to choose ETFs for retirement.
Equal weight and cap weight took turns leading for a decade at a time, so the hard part of either choice is sticking with it through the stretch when the other one wins.
It can be part of a portfolio if you want less concentration and accept a 0.20% fee. From May 2003 to Sep 2026 it returned 11.3% a year vs 11.5% for the S&P 500, but it trailed by 3.9 points a year from 2017.
It depends on the period. RSP led by 2.4 points a year from 2003 to 2016; the cap-weighted S&P 500 led by 3.9 points a year from 2017 to Sep 2026. Over the whole time they were about even.
RSP charges 0.20% vs 0.03% and trades much more: it resets all 500 companies to equal weight every quarter, giving 27% turnover vs 2.4% for VOO.
Not reliably. RSP fell less in 2022 (−21.4% vs −24.5%) but more in 2007–09 (−59.2% vs −55.2%) and in the 2020 crash (−39.0% vs −34.0%), Exent market data.
Quarterly. At each rebalance every S&P 500 company is set to the same weight, so the fund trims recent winners and adds to laggards.
Some investors blend them to dilute concentration. Illustrative: 80% VOO and 20% RSP lowers the top-10 share from 40.6% to about 33.0% and raises the blended fee from 0.03% to about 0.064%.
There are no lasting top holdings: every company is reset to about 0.2% each quarter, so the largest positions are simply recent risers. On Oct 20, 2026 the top 10 together were 2.7% of the fund.
It reduces it rather than avoiding it: information technology was 18.0% of RSP (Oct 20, 2026) vs 39.7% of VOO (Sep 30, 2026). Nvidia, Apple and Microsoft are still held, each at about the same weight as every other company.
Market intel provides a Risk ON / Neutral / Risk OFF reading from four pillars, cross-asset analysis, an events calendar and regular written notes. Context for reviewing a plan, not a crash forecast.
Educational content, not investment advice. Examples are illustrative; past performance does not guarantee future results.