QQQ vs. VOO: Holdings Overlap, Concentration, and Basket Analysis

This guide asks what changes when an investor holds QQQ, VOO, or both. It does not rank recent returns or recommend a ticker. We compare the two funds’ equity positions for the same reporting date, then show how the overlap and different weights affect a dollar allocation. The count of shared securities and the share of fund assets represented by those holdings are separate measures: 88 shared identifiers does not mean 88% of either fund’s assets overlap.

QQQ carries the name Invesco QQQ Trust, Series 1, and is designed to track the Nasdaq-100 Index before fees and expenses. VOO is Vanguard’s S&P 500 ETF, designed to track the S&P 500. Their objectives and current fund details are described by Invesco and Vanguard.

Although “Trust” remains in QQQ’s name, after the market close on December 19, 2025, it was reclassified from a unit investment trust (UIT) to an open-end management investment company. Its Nasdaq-100 investment objective stayed the same. The December 2025 SEC prospectus describes the change and current structure.

The Nasdaq-100 measures large companies primarily listed on a Nasdaq-affiliated exchange, excluding companies classified in the financial industry. It can include eligible foreign issuers and more than one share class from a company. Its weighting uses modified market capitalization rather than a simple equal split or an unadjusted market-cap formula. Since May 1, 2026, Nasdaq’s methodology distinguishes full market capitalization used for selection from modified market capitalization used for weights; the latter reflects eligible listed shares and limits the share count used for low-float securities. The index is reconstituted annually and rebalanced quarterly, with concentration constraints and a fast-entry process under specified conditions. Read the current Nasdaq-100 methodology and Nasdaq’s 2026 methodology update.

The S&P 500 represents large U.S. companies selected under S&P Dow Jones Indices’ eligibility rules and committee process. It is float-adjusted market-cap weighted: companies with more publicly tradable shares and larger market value generally carry more weight. Sector representation, financial viability, liquidity, and public float form part of the selection framework. Unlike the Nasdaq-100, the S&P 500 is not restricted to Nasdaq-listed firms and does not exclude financial companies as a class. The S&P U.S. methodology and S&P 500 overview describe its construction.

That distinction helps explain sector exposure without turning QQQ into a technology-only fund. Its eligibility universe and largest weights tend to create heavier exposure to technology and growth-oriented companies, while the S&P 500 spans financials, health care, industrials, energy, consumer sectors, and other industries. Neither index’s name alone tells you each company’s current weight, and the sector mix changes as prices and constituents change.

The latest common public reporting date in these two filings is June 30, 2026. QQQ’s Form N-PORT was filed August 28, 2026 under accession 0001067839-26-000030; the Vanguard 500 Index Fund report containing VOO was filed the same day under accession 0000036405-26-000473. We retained equity-category positions, matched by ISIN first, and checked CUSIP or LEI when a security had no ISIN. Generic values such as N/A were not treated as identifiers. The source files are the QQQ filing and the VOO series filing.

QQQ reported 102 ISIN-identified equity positions. The VOO fund-series report contained 506 equity rows: 504 had ISINs and two residual corporate-action securities were identified through other filing fields. A reported position row is not the same unit as an index company. A company can have multiple share classes with separate identifiers, and fund filings can show small residual positions that are not ordinary index constituents. We therefore describe the count as security identifiers, not as the number of companies in either index.

There were 88 shared equity identifiers. Their reported weights sum to 95.379182% of QQQ net assets and 54.507995% of VOO net assets. All equity positions together represented 99.926878% and 99.749246%, respectively. The small balances outside those equity totals include non-equity holdings and filing-level rounding. VOO’s N-PORT is filed for Vanguard 500 Index Fund, a series with several share classes including VOO; its entire series net-asset value should not be presented as VOO-only assets. We compare its reported positions and weights, not a ticker-specific asset total.

QQQ’s ten largest equity securities totaled 45.000248% of its reported net assets; VOO’s ten largest totaled 36.403437%. The higher QQQ figure is consistent with a basket whose largest Nasdaq-listed non-financial companies have more influence, even after the index’s weighting constraints. The fund holdings are not equally weighted.

The table is sorted by 50:50 blended weight, not by either fund’s separate ranking. It lists the ten largest shared securities in a hypothetical equal-dollar allocation. Alphabet Class A and Class C are separate securities with distinct ISINs. Individual weights are rounded to two decimal places; the total uses unrounded filing values, so displayed rows may not add exactly.

A shared security can still have very different weights. Micron was 5.6380% of QQQ and 2.0186% of VOO; AMD was 4.1026% and 1.4688%. Matching the ISIN establishes that the same share class appears in both baskets, not that the funds allocate the same dollars to it. Price changes after June 30 also change weights.

Examples of equity identifiers found in QQQ but not VOO include ASML at 0.7896%, Arm at 0.6511%, and Shopify at 0.6031% of QQQ’s reported net assets. These are foreign-domiciled companies with eligible Nasdaq listings. Examples found in VOO but not QQQ include Eli Lilly at 1.4712%, Berkshire Hathaway at 1.4224%, and JPMorgan Chase at 1.2558% of VOO’s net assets. The Nasdaq-100’s financial-industry screen is one structural reason a bank such as JPMorgan is absent from QQQ. A single rule does not explain every unmatched position: listing, domicile, eligibility, timing, and residual holdings all matter.

These examples also show why “QQQ is tech; VOO is the whole U.S. market” is too simple. QQQ selects from an exchange and industry-eligibility universe and contains companies from several sectors. VOO follows a committee-selected large-cap U.S. index, not every U.S. stock. Compare the rules and the actual holdings instead of inferring a fund’s entire exposure from its label.

Suppose an investor puts $5,000 into QQQ and $5,000 into VOO, for $10,000 total. A shared company’s blended weight is the dollar-weighted average of its two fund weights. For NVIDIA, the filing reported 7.5967566% in QQQ and 7.5142372% in VOO, so the mix is (7.5967566% + 7.5142372%) ÷ 2 = 7.5554969%. That is about $755.55 of the $10,000 allocation using the June weights.

Applying that calculation to all 88 shared securities gives 74.9435885% of the combined allocation. QQQ-only equities account for about 2.2738477% of the mix; VOO-only equities account for about 22.6206257%. Together with the shared positions, those figures reconcile to the average equity exposure reported by the two filings. This is a dollar-weighted holdings calculation, not a score showing that the portfolio is “75% diversified.”

For any security with weights wQQQ and wVOO, and dollar investments a and b, the combined weight is (a × wQQQ + b × wVOO) ÷ (a + b). A 70:30 allocation therefore uses 0.70 × wQQQ + 0.30 × wVOO. To estimate whole-account exposure, also include individual stocks, other funds, options, and cash holdings. Counting tickers alone can miss how much of the same company is held indirectly.

Eighty-eight shared identifiers measure holdings overlap, not correlation, volatility, drawdown, future return, or the risk of an investor’s entire account. A return comparison would need the same period, currency, distribution-reinvestment convention, market-price or NAV basis, and treatment of fees. The SEC filings show one reporting-date portfolio; index membership, corporate actions, trades, and market prices change it. Nasdaq’s concentration rules can adjust weights but cannot prevent losses or guarantee that any company stays below a fixed weight.

The filing scope matters too: VOO’s report is at the Vanguard 500 Index Fund series level. The SEC-reported percentages are fund portfolio values, not the price a buyer will receive in the market. They do not include a reader’s other accounts, personal taxes, or execution costs. Recalculate company-level dollar exposure from current holdings and actual account balances before making a portfolio decision.

If you want to compare VOO with broader U.S. market coverage, see the VTI–VOO holdings overlap analysis. For overlap among S&P 500 trackers, see the SPY–IVV–VOO basket comparison.