The regular-session close and the after-hours price refer to different times. If trading continues after the regular session ends, the last traded price can change. That does not rewrite the regular-session closing price. When two apps show different numbers, first check the trading session, timestamp and type of price beside each number.

Which session does the closing price belong to?

For US stocks, the closing price usually means the price at the end of regular trading. A typical regular session runs from 9:30 a.m. to 4 p.m. US Eastern Time, but holidays and early closes require a separate schedule check. Premarket, after-hours and overnight availability varies by market and broker.

Investor.gov’s explanation of closing prices notes that some media outlets and data providers may display the last extended-hours trade as the day’s closing price. Even a number simply labeled “close” therefore needs context: is it the regular-session close, or the last price including extended-hours trading?

Number on the screen What to check
Regular-session close Is this the closing price for that trading day’s regular session?
Last after-hours price Is this the most recent completed trade during the after-hours session?
Bid or ask Is this a completed trade or a currently quoted order price?
Delayed quote How far behind the current time is the displayed timestamp?

The last traded price is not necessarily the price available to you now. Orders may have changed since that trade, and the bid and ask can differ.

Check the baseline behind a percentage change

The following are hypothetical prices used to illustrate the calculation. They are not prices observed for a real company or records of actual trades.

Time and price type Hypothetical price Comparison and percentage change
Previous trading day’s regular close $98 Baseline
Today’s regular close $100 About +2.04% versus $98
Today’s last after-hours trade $103 +3.00% versus today’s $100 close
The same after-hours price versus the previous close $103 About +5.10% versus $98

The formula is (current price ÷ comparison price − 1) × 100. The same $103 price is up 3% versus $100 and about 5.10% versus $98. Reading “+3%” as the entire day’s gain can mix two different baselines.

When describing a move after earnings, separate the regular-session change from the after-hours change. In this example, a precise description would be: “The stock closed about 2.04% higher in regular trading, then gained 3% after hours relative to that close.”

Why can prices move more sharply after hours?

The SEC’s extended-hours trading bulletin explains that fewer participants can mean lower liquidity, wider spreads and greater volatility. Company announcements outside regular trading can also trigger price changes.

If an after-hours percentage looks unusually large, check the volume and time of the last trade as well. A last price formed by a small number of trades should not be treated as broad agreement among market participants. Prices can also differ across trading systems.

FINRA’s extended-hours risk disclosure states that after-hours prices may differ from both the regular close and the next day’s opening price. A $103 after-hours trade does not establish that the next regular session will open at $103.

What to compare when two apps disagree

  1. Match the security. Check the ticker, exchange, share class and currency.
  2. Match the session. Identify regular, premarket, after-hours or overnight trading.
  3. Match the time. Check the latest update, any delay and the time zone. The Korean calendar date can differ from the US trading date.
  4. Match the price type. Distinguish the last trade from the bid or ask.
  5. Match the baseline. Check whether the percentage is relative to the previous regular close or today’s regular close.

If a difference remains, look at each app’s market-data coverage and price definitions. Different numbers alone do not establish that one app is wrong.

Trading access and order conditions need a separate check

This article explains how to read prices. Check your broker’s guidance for available sessions, supported securities, order types and the handling of unfilled orders. Seeing an after-hours last price does not mean your order will execute at that price.

A 4 p.m. US Eastern close corresponds to 5 a.m. the following day in Korea during US daylight saving time, and 6 a.m. during standard time. Record the trading date and time zone rather than comparing calendar dates alone.

Instead of recording only “close: $100,” include the basis: “US trading date [date], regular close $100; last after-hours trade at [time] $103; source [provider].” That makes later comparisons easier to interpret.

Sources were checked as of November 9, 2026. Trading hours and order conditions can change, so also check the current information from your market and broker.

Photo: Billie Grace Ward, original on Wikimedia Commons, CC0 1.0. Photographed January 5, 2021; cropped to 16:9.