Direct answer: An ETF's NAV equals the market value of all holdings minus liabilities, divided by shares outstanding, computed after the US market close each day. The intraday indicative NAV (iNAV) is a real-time estimate. Authorized participants arbitrage away persistent price-NAV gaps through the creation-redemption process.
How ETF NAV Is Calculated
Key Takeaways
- Official NAV is calculated once daily after the 4 p.m. ET market close using closing prices from each security's primary exchange.
- Intraday iNAV updates every 15 seconds but uses stale prices for illiquid or foreign holdings, so discounts and premiums for those ETFs are estimated.
- Premium or discount to NAV is normal intraday; persistent premiums or discounts signal potential arbitrage friction.
- For fixed-income and international ETFs, price-to-NAV gaps can be wider because underlying securities trade on different schedules or with lower liquidity.
The Daily NAV Calculation
Each business day, the ETF's administrator values every position at its official closing price, adds accrued income, subtracts liabilities including management fees, and divides by shares outstanding to arrive at NAV per share. For most domestic equity ETFs this is straightforward; for fixed-income or international ETFs, fair-value pricing rules may substitute model prices for stale exchange quotes.
Intraday NAV and Its Limitations
Exchanges publish an intraday indicative value (IIV or iNAV) every 15 seconds during market hours. This estimate uses real-time prices for liquid holdings but may use the prior day's close for foreign stocks outside their trading hours, making the iNAV for international ETFs an approximation rather than a true real-time value.
Creation and Redemption Keep Price Close to NAV
Authorized participants can exchange a basket of the underlying securities for newly created ETF shares (or vice versa) at NAV. If the ETF trades at a premium, APs sell the ETF short, buy the basket, and create shares to cover, eliminating the gap. If it trades at a discount, they buy ETF shares, redeem them for the basket, and sell the basket at a profit. This mechanism keeps most liquid ETF premiums and discounts under 0.1% on normal trading days.
When Premiums and Discounts Persist
During market stress or when underlying assets are illiquid, creation-redemption becomes costly or risky and premiums or discounts can widen significantly. Fixed-income ETFs historically trade at premiums during periods of low bond market liquidity, as the ETF price reflects real-time supply and demand while NAV uses potentially stale bond quotes.
Frequently Asked Questions
How often is an ETF's NAV calculated?
Official NAV is calculated once daily, after the US market close at 4 p.m. ET. The intraday indicative value (iNAV) is updated every 15 seconds during trading hours but is an estimate, not an official figure.
What does it mean when an ETF trades at a premium or discount?
A premium means the ETF's market price is above its NAV; a discount means below. Small intraday premiums and discounts are normal due to bid-ask spreads and timing. Persistent gaps over multiple days suggest limited arbitrage activity, often because underlying securities are illiquid or hard to trade.
Can retail investors arbitrage ETF premiums and discounts?
No. The creation-redemption mechanism is reserved for large institutional authorized participants who transact in creation units, typically 25,000 to 100,000 shares. Retail investors can take advantage of premiums and discounts by buying a discounted ETF or selling a premium one, but cannot directly force the gap to close.