When Does the American Stock Market Open Today? Complete Guide to Global Schedules in 2025

Understanding the opening hours of the US stock exchange today and the major global markets is essential for those operating in international financial markets. The synchronization between different financial centers determines trading volumes, available liquidity, and periods of higher volatility—critical elements for any investment strategy on a global scale.

Main Stock Exchange Operating Hours in 2025

US Market

The US stock exchange today opens according to the following hours:

• NYSE and NASDAQ (New York): 9:30 AM to 4:00 PM (EST), equivalent to 10:30 AM to 5:00 PM (BRT) during the non-DST period
• Pre-market: 4:00 AM to 9:30 AM (EST), or 6:00 AM to 11:30 AM (BRT)
• After-hours: 4:00 PM to 8:00 PM (EST), or 5:00 PM to 9:00 PM (BRT)

Other Relevant Markets

*Time refers to the previous day

B3: Brazilian Stock Exchange Hours in 2025

B3 (Brazilian Stock Exchange) structures its operations across multiple segments, each with specific hours:

Starting March 10, 2025:

• Spot and Fractional Market: 10:00 AM to 4:55 PM
• Futures Market: 10:00 AM to 5:25 PM
• Options Market: 10:00 AM to 4:55 PM
• Ibovespa Futures and Mini Contracts: 9:00 AM to 6:25 PM
• Dollar and Exchange Futures: 9:00 AM to 6:30 PM

These adjustments reflect B3’s effort to synchronize with international markets, facilitating arbitrage operations and continuous trading flows.

Holidays with closure: January 1, Carnival (March 4), and Christmas (December 25).

Regulatory Changes in 2025

Several markets have implemented significant changes:

• India: Abolished daylight saving time in 2024, maintaining IST (UTC+5:30) fixed year-round
• Saudi Arabia: Adopted UTC+3 permanently, aligning with other Gulf markets
• Emerging Markets: African exchanges like Johannesburg Stock Exchange (9:00 – 17:00 UTC+2, equivalent to 4:00 – 12:00 BRT) and Tadawul have increased their international relevance

Overlap Windows: Maximum Liquidity

Periods when multiple markets operate simultaneously offer the best conditions for executing large-volume orders:

• US + Europe: 10:30 AM to 1:30 PM (BRT) – NYSE and LSE active simultaneously
• Asia + Europe: 9:00 PM to 3:00 AM (BRT) – partial operations between Tokyo and London
• Brazil + US: 10:30 AM to 5:00 PM (BRT) – peak activity period on B3

These overlaps amplify liquidity and reduce spreads, making them ideal windows for strategies involving multiple markets.

Why These Hours Matter

Knowing precisely when each exchange opens is essential to optimize returns. In the first minutes after opening, volatility tends to be high, reflecting price adjustments to news and movements that occurred outside market hours. For active traders, this initial period presents both opportunity and increased risk.

Additionally, understanding time zones allows planning strategies that exploit overlaps between markets. Sophisticated investors use these windows for arbitrage, hedging positions, and executing orders with better liquidity. The ability to operate across different exchanges synchronously becomes a competitive advantage in increasingly interconnected global markets.

To stay updated on possible changes to these hours, it is advisable to regularly consult the official websites of the exchanges, especially considering occasional adjustments in holiday calendars or changes in daylight saving policies.