Net Asset Value (NAV)

Net asset value (NAV) is the per-share value of an ETF calculated by dividing the total market value of all the fund’s holdings — minus any liabilities — by the number of shares outstanding.

How Net Asset Value Works

NAV is calculated once per day, after the US stock market closes at 4:00 PM Eastern Time. The fund’s administrator takes the closing prices of every security in the portfolio, totals them up, subtracts any liabilities (such as accrued fees), and divides by the total number of ETF shares outstanding.

For example: if an ETF holds assets worth $500 million and has 10 million shares outstanding, its NAV is $50 per share. If the fund earns returns or its holdings rise in value, the NAV rises accordingly.

For ETFs, NAV is the theoretical fair value of each share. However, because ETFs trade on an exchange throughout the day — unlike mutual funds, which only transact at NAV — an ETF’s market price can differ slightly from its NAV at any given moment during trading hours.

How Is NAV Measured?

NAV is expressed as a dollar amount per share and is published daily by the fund issuer after market close. A closely related figure — the intraday NAV (iNAV) — is estimated and published every 15 seconds during trading hours to give investors a real-time approximation of fair value.

The difference between an ETF’s market price and its NAV is called the premium (when market price is above NAV) or discount (when below). For large, liquid ETFs like SPY or VOO, this gap is typically less than 0.05% — nearly negligible. For smaller or less liquid ETFs, the premium or discount can be wider.

VOO (Vanguard S&P 500 ETF) consistently trades within a fraction of a cent of its NAV, reflecting its massive liquidity and the efficiency of its authorized participant mechanism.

SPY (SPDR S&P 500 ETF Trust) also maintains an extremely tight NAV-to-price relationship, with a premium or discount that rarely exceeds 0.05% under normal market conditions.

BND (Vanguard Total Bond Market ETF) sometimes shows slightly wider NAV deviations during periods of bond market stress, when the underlying bonds are harder to price in real time.

NAV is the calculated fair value of an ETF’s underlying holdings. Market price is what buyers and sellers agree to pay for a share on the exchange right now — which can be slightly above (premium) or below (discount) NAV.

For mutual funds, investors always buy and sell at NAV. For ETFs, you buy and sell at the market price. In practice, for highly liquid ETFs, the two figures are nearly identical because arbitrage keeps them aligned. The distinction matters more for illiquid or niche ETFs.

Related: [Premium Discount to Nav]

Frequently Asked Questions About Net Asset Value

Should I buy an ETF when it trades at a premium or discount to NAV?

For large, liquid ETFs, the premium or discount is usually so small — often under 0.05% — that it has no meaningful impact on your returns. For smaller or more specialized ETFs, a persistent large premium is worth noting, as you may be paying more than the underlying assets are worth. Always check the premium/discount history on ETF.com before buying a niche ETF.

How is ETF NAV different from stock price?

A stock price reflects what the market believes a company is worth. An ETF’s NAV is a mathematical calculation based on the actual current market value of every security the fund holds. NAV is grounded in the real-time value of underlying assets; a stock price is based on expectations about future earnings and growth.

Does NAV change during the trading day?

The official NAV is only calculated once per day, after market close. However, an estimated intraday NAV (iNAV) is calculated and published approximately every 15 seconds during trading hours by the fund issuer or a designated calculation agent. The iNAV is an estimate, not an official value, and may lag real-time price movements in fast-moving markets.

RELATED_TERMS: Expense ratio, [Market price], [Premium and discount to NAV], [Intraday NAV], Assets under management

Disclaimer: The information in this article is for educational and informational purposes only. It does not constitute financial, investment, or tax advice. Past performance is not indicative of future results. Investing in ETFs involves risk, including possible loss of principal. Always consult a qualified financial advisor before making investment decisions.