Wealthy PotMGK vs VOO: MGK Is the Top Half of VOO, Weighted Toward Growth
VOO owns the whole S&P 500. MGK owns only the largest US growth companies, about 56 of them, and almost all of them are already in VOO. In the two funds' 30 June 2026 SEC filings, 99.0% of MGK's money sat in stocks VOO also held, and the overlap between the funds was 50.9%. The other half of VOO is what MGK leaves out: Berkshire Hathaway, JPMorgan, Johnson & Johnson, Exxon, Walmart and about 440 more companies. MGK charges 0.05% and VOO 0.03%. Over the ten years to 30 September 2026, MGK returned 19.00% a year and VOO 15.29%, with more volatility along the way. MGK is a growth bet. VOO is the market.
Table of Contents
The Short Answer
- Overlap: 50.9%. 53 of MGK's 55 holdings were also in VOO, and they made up 50.9% of VOO. Our calculation from both funds' 30 June 2026 SEC filings.
- Fees: MGK 0.05%, VOO 0.03%. MGK's fee fell from 0.07% on 2 February 2026. On $10,000 that is $5 against $3 a year.
- Holdings: 56 vs 505 stocks at 31 August 2026.
- Top ten: 66.8% vs 37.9% of the fund at 30 June 2026. Two thirds of MGK sits in ten companies.
- Ten-year return to 30 September 2026: MGK 19.00%, VOO 15.29% a year at NAV. Over the latest year, VOO was slightly ahead.
- Risk: MGK swings harder. Three-year standard deviation 17.72% against 13.06%, and a worst quarter of -22.54% against -19.63% in the prospectuses.
- Holding both works only if you want a deliberate growth tilt. MGK adds no new companies to VOO; it doubles up on the ones VOO already owns.
How Much of VOO Is Already in MGK
Both funds file their full portfolios with the SEC, and both filings used here are dated 30 June 2026. We matched them holding by holding with the same data behind our Portfolio Overlap Checker.
| Portfolios at 30 June 2026 | MGK | VOO |
|---|---|---|
| Stock holdings in the filing | 55 | 501 |
| Held by both funds | 53 | 53 |
| Share of the fund in those shared holdings | 99.0% | 50.9% |
| Holdings the other fund did not own | 2 (0.8% of MGK) | 448 (48.8% of VOO) |
| Overlap, sum of the smaller weight in each shared stock | 50.9% | |
The two MGK holdings outside VOO were Space Exploration Technologies (SpaceX), 0.48% of MGK, and Snowflake, 0.33%. Neither was an S&P 500 member on that date. Everything else in MGK was in VOO, just at a much bigger weight:
| Weight at 30 June 2026 | MGK | VOO |
|---|---|---|
| NVIDIA | 13.27% | 7.51% |
| Apple | 12.17% | 6.59% |
| Alphabet | 10.58% | 5.84% |
| Microsoft | 7.50% | 4.30% |
| Amazon | 4.46% | 3.62% |
| Broadcom | 4.27% | 2.77% |
| Meta Platforms | 4.08% | 1.92% |
| Tesla | 3.93% | 1.84% |
| Eli Lilly | 3.40% | 1.47% |
| AMD | 3.19% | 1.47% |
What VOO has that MGK does not. The largest VOO positions missing from MGK were Micron (2.02% of VOO), Berkshire Hathaway (1.42%), JPMorgan (1.26%), Johnson & Johnson (0.95%), Exxon (0.88%), Walmart (0.77%), Caterpillar (0.76%), Cisco (0.72%), AbbVie (0.69%), Costco (0.64%), GE (0.60%) and UnitedHealth (0.59%). Banks, energy, consumer staples, most of health care and the smaller S&P 500 companies: 448 holdings, 48.8% of VOO.
MGK vs VOO Side by Side
| MGK | VOO | |
|---|---|---|
| Full name | Vanguard Morningstar Mega Cap Growth ETF | Vanguard S&P 500 ETF |
| Index | Morningstar US Mega Cap Growth Index (CRSP US Mega Cap Growth until 29 July 2026) | S&P 500 |
| Expense ratio | 0.05% (0.07% before 2 Feb 2026) | 0.03% |
| Prospectus cost on $10,000 over 10 years | $64 | $39 |
| Number of stocks (31 Aug 2026) | 56 | 505 |
| Top-10 weight (30 Jun 2026) | 66.8% | 37.9% |
| Median market cap (30 Jun 2026) | $1,797.3 billion | $455.6 billion |
| Price/earnings ratio (30 Jun 2026) | 35.7x | 27.5x |
| 3-year standard deviation (30 Jun 2026) | 17.72% | 13.06% |
| 30-day SEC yield (30 Sep 2026) | 0.30% | 1.00% |
| ETF share class assets (31 Aug 2026) | $33.5 billion | $1.0 trillion |
| Mutual fund version | Institutional Shares only, $5 million minimum | Admiral Shares (VFIAX), 0.04%, $3,000 minimum |
| Inception | 17 Dec 2007 | 7 Sep 2010 |
Sector weights are not directly comparable. Vanguard reports MGK's sectors on the ICB system (72.7% "Technology" at 30 June 2026) and VOO's on GICS (38.0% "Information Technology"). ICB counts Alphabet and Meta as technology; GICS puts them in communication services. The holdings table above is the cleaner comparison: MGK held almost no banks (0.7% financials on ICB) where VOO held 11.8% on GICS.
Where They Really Differ
Breadth. MGK's prospectus describes its index as growth companies "in the top 70% of investable U.S. equity market capitalization." Two filters apply: size (only the largest companies) and style (only those classed as growth). VOO applies neither. It holds every S&P 500 company by market value, growth and value alike.
Concentration. Because MGK weights its few dozen names by market value, NVIDIA, Apple and Alphabet alone were 36.0% of the fund on 30 June 2026, against 19.9% of VOO. MGK's top 25 holdings were 85.2% of the fund; VOO's were 51.7%. When those few companies fall together, MGK has nothing else to lean on.
Income. MGK's SEC yield was 0.30% against VOO's 1.00% at 30 September 2026. On $100,000 that is about $300 a year of dividends against $1,000. The lower yield also means less taxable income each year in a brokerage account, which shows up in the prospectus after-tax figures below.
Cost. Two basis points: $20 a year on $100,000. Small, but it runs against MGK every year.
Returns and What Drove Them
| Annualized NAV return, to 30 Sep 2026 | 1 year | 3 years | 5 years | 10 years |
|---|---|---|---|---|
| MGK | 15.51% | 27.41% | 15.11% | 19.00% |
| VOO | 15.70% | 22.85% | 13.75% | 15.29% |
| MGK minus VOO | -0.19 | +4.56 | +1.36 | +3.71 |
Over three, five and ten years the largest growth companies beat the rest of the market, and MGK captured that. Over the latest year they did not, and VOO edged ahead. The five-year gap is smaller, 1.36 points. That window starts in October 2021 and takes in 2022, which contains MGK's worst prospectus quarter, a 22.54% loss.
| Average annual total return to 31 Dec 2025 | 1 year | 5 years | 10 years |
|---|---|---|---|
| MGK, before taxes | 20.71% | 15.74% | 18.35% |
| MGK, after taxes on distributions | 20.60 | 15.60 | 18.12 |
| VOO, before taxes | 17.84% | 14.38% | 14.78% |
| VOO, after taxes on distributions | 17.50 | 13.99 | 14.32 |
Taxes on distributions cost MGK 0.23 points a year over the ten years to 2025 and VOO 0.46, our arithmetic from those tables. That is the lower yield at work, and it narrows the cost gap for a taxable account. The volatility runs the other way: the prospectuses put MGK's best quarter at +28.80% and worst at -22.54%, against +20.54% and -19.63% for VOO.
| Hypothetical $10,000 held for 10 years | Ending value |
|---|---|
| At VOO's 10-year NAV return to 30 Sep 2026 (15.29%) | $41,487 |
| At MGK's 10-year NAV return to 30 Sep 2026 (19.00%) | $56,947 |
That decade is the whole case for MGK, and also its risk. The result came from a small group of companies doing extremely well. If leadership broadens out to banks, energy, health care or smaller firms, VOO owns them and MGK does not.
This is educational information, not personalized investment advice. Past performance does not guarantee future results, and all investing carries the risk of loss.
Which One Fits You
One fund for the core of a portfolio? VOO. It is cheaper, it holds about nine times as many companies, it pays more income, and its swings have been smaller. MGK's companies are already half of VOO.
Choose MGK if you already own broad funds elsewhere and want a deliberate tilt toward the largest growth companies, and you can hold through a 20%-plus quarterly drop without selling. That is a choice about concentration, not a better version of VOO.
Holding both? VOO plus MGK is effectively VOO with the giants overweighted. It is a legitimate tilt if you size it on purpose, for example a small MGK slice next to a VOO core. It is not diversification, because MGK adds two companies VOO lacks and 0.8% of new money.
Taxable account. Both are ETFs with low tax drag. MGK's lower yield means less dividend tax each year. If you already hold one with a gain, redirect new money rather than selling; check your 2026 tax bracket first.
401(k) or mutual fund only. MGK's only mutual fund class is Institutional Shares with a $5 million minimum. An S&P 500 index fund is on most 401(k) menus, and VOO's Admiral twin, VFIAX, charges 0.04% with a $3,000 minimum at Vanguard.
Other ways to tilt toward growth. A broader growth fund holding about 147 stocks is VUG, compared in VUG vs VOO and MGK vs VUG. The Nasdaq-100 version is MGK vs QQQ, and the S&P 500's own growth half is SPYG vs VOO.
Sources & Methodology
- Vanguard World Fund, Form 485BPOS filed 28 January 2026: MGK's index description, Institutional Shares minimum, best and worst quarters, and returns to 31 December 2025.
- MGK supplement effective 2 February 2026: the fee restated to 0.05% and the $64 ten-year cost example.
- MGK renaming supplement, 29 July 2026: the CRSP to Morningstar name change.
- VOO summary prospectus dated 28 April 2026: fee table, cost example, best and worst quarters, returns to 31 December 2025.
- MGK fact sheet, 30 June 2026 and VOO fact sheet, 30 June 2026: top ten, sectors, median market cap, P/E and standard deviation.
- Vanguard MGK page and Vanguard VOO page: fees, stock counts and assets at 31 August 2026, SEC yields and returns to 30 September 2026.
- MGK Form N-PORT, 30 June 2026 and VOO Form N-PORT, 30 June 2026: the holdings behind the overlap figures.
How the overlap was computed. For each company both funds hold we took the smaller of its two weights and added them up, the method the Portfolio Overlap Checker uses on the same N-PORT data. Both filings are dated 30 June 2026.
What we did not verify. We did not open Morningstar's index rulebook, so we do not explain why particular large companies (Micron, for example) fall outside MGK's growth screen. We state only what the filings show.
This article is for general education and is not investment, tax or legal advice. Past performance does not guarantee future results, index returns cannot be invested in directly, and all investing carries the risk of loss. Figures were checked against the sources above on 5 October 2026; confirm current data with Vanguard before acting.
FAQ: MGK vs VOO
Is MGK better than VOO?
It returned more over ten years, 19.00% against 15.29% a year to 30 September 2026, but with higher volatility, a lower yield, a higher fee and two thirds of its money in ten stocks. VOO is the broader, cheaper core holding. MGK is a growth tilt.
How much do MGK and VOO overlap?
50.9% by weight in both funds' 30 June 2026 filings. 99.0% of MGK's money was in companies VOO also held.
Should I hold MGK and VOO together?
Only as an intentional tilt toward mega-cap growth. MGK adds almost no new companies to VOO; it raises your weight in NVIDIA, Apple, Alphabet and Microsoft.
What is MGK's expense ratio?
0.05% since 2 February 2026, down from 0.07%. VOO's is 0.03%.
Why does MGK hold SpaceX if VOO does not?
MGK's index is not limited to S&P 500 members. At 30 June 2026 it held SpaceX (0.48%) and Snowflake (0.33%), neither of which was in VOO's filing.
Which pays more dividends?
VOO. Its 30-day SEC yield was 1.00% at 30 September 2026, against 0.30% for MGK.
Did MGK change its name?
Yes. On 29 July 2026 it became the Vanguard Morningstar Mega Cap Growth ETF, tracking the Morningstar US Mega Cap Growth Index. The ticker and strategy did not change.
Cite This Page
Journalists, educators and bloggers are welcome to cite this comparison. Please link back so readers can reach the underlying filings.
"MGK vs VOO: MGK Is the Top Half of VOO, Weighted Toward Growth." Wealthy Pot, 2026. https://wealthypot.com/mgk-vs-voo/
Related comparisons: MGK vs VUG · MGK vs QQQ · VUG vs VOO · QQQ vs VOO · SPYG vs VOO · VIG vs VOO · All ETF comparisons
