---
title: "VTI samples the U.S. stock market, and its net asset value has stayed within 0.01 percentage point of the index"
url: "https://etf.net/news/vti-sampling-tracks-index-closely-2026-11-09"
published_at: "2026-11-09T17:46:03.891Z"
updated_at: "2026-11-09T17:46:03.891Z"
byline: "ETF.net Research"
---

# VTI samples the U.S. stock market, and its net asset value has stayed within 0.01 percentage point of the index

Vanguard warns that sampling can mean more tracking error, but through Sept. 30, 2026, net asset value matched for the year to date and over one, five and 10 years, and trailed by 0.01 percentage point over three years.

By ETF.net Research. Published Nov 9, 2026.

Vanguard Morningstar Total Stock Market ETF, VTI, formerly Vanguard Total Stock Market ETF, does not hold every security in the index it tracks.

Vanguard builds the portfolio by sampling. Its prospectus says sampling may be more likely to leave a gap versus the index than holding the index's own stocks. Through Sept. 30, 2026, the gap on net asset value was no wider than **0.01** percentage point for the year to date and for one, three, five and 10 years.

## A sample, not a copy

The index is the Morningstar US Total Market Index. Vanguard's [summary prospectus](https://www.sec.gov/Archives/edgar/data/36405/000003640526000197/f44849d1.htm), dated April 28, 2026, says VTI "invests by sampling the Target Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Target Index in terms of key risk factors and other characteristics."

The portfolio is built to behave like the index. The same prospectus says VTI does not hold all of the securities in it.

In Vanguard's U.S. stock index [prospectus](https://advisors.vanguard.com/assets/corp/fund_communications/pdf_publish/us-products/prospectuses/i855.pdf), dated the same day, every other fund in that prospectus replicates. Each of them "uses the replication method of indexing, meaning that each of these Funds generally holds the same stocks as those in its Target Index and in approximately the same proportions." VTI is the one that samples.

That prospectus describes the index as market-cap-weighted, so larger companies count for more of it, and says it seeks to represent 100% of the investable U.S. equity market, as the index provider defines that market. It includes large-, mid-, small- and micro-cap stocks that trade regularly on the New York Stock Exchange and Nasdaq.

On Dec. 31, 2025, the index held 3,494 stocks. The index provider reviews and rebalances the list every quarter.

Both April 28 prospectuses called the index the CRSP US Total Market Index, from the Center for Research in Security Prices. Vanguard renamed the index and VTI on July 29, 2026, and said the investment objective, strategies and policies were unchanged.

Morningstar said on July 28: "The rebrand affects naming only. Index methodologies will remain unchanged, and clients will experience no disruption in service."

## Ten companies are 36.1% of VTI

On Sept. 30, 2026, ten companies were 36.1% of VTI's net assets, the [fact sheet](https://fund-docs.vanguard.com/F0970.pdf) shows. Nvidia was 7.1%, Apple 6.6% and Microsoft 5.2%. Technology was 43.1% of net assets.

Chart: **Nvidia** is VTI's largest holding

## The ETF is part of a $2.32 trillion fund

VTI is an exchange-traded share class of Vanguard Morningstar Total Stock Market Index Fund, meaning its owners hold that fund's portfolio. On Sept. 30, 2026, VTI accounted for $689.2 billion of the fund's $2.32 trillion. The same portfolio is also sold as mutual fund shares, which are not listed on an exchange.

VTI is listed on NYSE Arca, and the shares must be held in a brokerage account.

The annual expense ratio is **0.03%**, or $3 a year on $10,000.

In the 20 sessions through Nov. 6, 2026, the shares traded $1.3 billion a day on average. Vanguard reported a 30-day bid-ask spread of 0.01% as of Nov. 6.

## Within a hundredth of a percentage point

Vanguard's [fact sheet](https://fund-docs.vanguard.com/F0970.pdf), as of Sept. 30, 2026, compares net asset value with what it calls the Spliced Total Stock Market Index. For the periods below, that benchmark is the index now called the Morningstar US Total Market Index. The splice uses earlier indexes only through June 2, 2013, and none of these windows reaches back that far.

Year to date is a cumulative return. The other figures are average annual returns.

Table: Period through Sept. 30, 2026, Net asset value, Index

Net asset value matched the index for the year to date and over one, five and 10 years. Over three years it trailed by 0.01 percentage point.

A buyer on the exchange pays the market price, not net asset value. Across the same windows, that return was no more than 0.02 percentage point from the index. The widest gap was over one year: a market-price return of 15.35%, against 15.33% for the index.

Vanguard's U.S. stock index prospectus says a sampling fund "may be more likely to experience tracking error than an index fund using a replicating strategy." The summary prospectus says that risk "may be heightened during times of increased market volatility or under other unusual market conditions." On net asset value, the gap versus the index had not exceeded a hundredth of a percentage point.

Source: etf.net, https://etf.net/news/vti-sampling-tracks-index-closely-2026-11-09. Please cite the page URL.