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QSI

Quantum-Si (QSI) After-Hours

DateAfter-hours PriceAfter-hours HighAfter-hours Low
$1.49$1.55$1.47

Quantum-Si (QSI) After-Hours Trading Summary

As of on , Quantum-Si (QSI) is trading at $1.49 in the after-hours session, down -$0.06 (-3.87%) from the regular market close of $1.55.

During after-hours trading, Quantum-Si (QSI) stock has ranged between $1.55 and $1.47, with the most recent trade recorded at $1.49.

24/5 trading

How to Buy or Trade Quantum-Si (QSI) After Market Close

Looking to trade Quantum-Si stock (QSI) after the market closes? Public offers 24/5 trading from Sunday at 8:00 PM ET through Friday at 8:00 PM ET, including after-hours and overnight trading. Keep in mind that extended-hours trading may involve lower liquidity and wider bid-ask spreads than normal sessions. Follow the steps below to get started.

  1. 1

    Create a Public brokerage account

    Sign up for a free brokerage account with Public. You can open an account directly on the website or by downloading the Public app for iOS or Android.

  2. 2

    Deposit funds into your account

    Add funds to your Public account by linking a bank account, using a debit card, or initiating a wire transfer, so you’re ready to invest during extended hours.

  3. 3

    Find Quantum-Si (QSI) stock and place your after-hours order

    Go to the Explore tab and type “Quantum-Si” or “QSI” into the search bar. Select the stock from the results to view its quote page. From there, you can enter the amount you’d like to invest and place an after-hours order directly.

  4. 4

    Track your Quantum-Si (QSI) shares in your portfolio

    Once your order is executed, Quantum-Si (QSI) will appear in your portfolio. You can track your QSI shares alongside other assets—including stocks, ETFs, crypto, bonds, options, and your high-yield cash account—all in one place on Public.

Quantum-Si (QSI) After-Hours Price History

Date
$1.55$1.49-3.87%
$1.43$1.36-4.90%
$1.07$1.20+12.15%
$0.97$0.97-0.38%
$0.80$0.83+4.39%
View all

FAQs About Quantum-Si (QSI) After hours

As of 8:00 PM ET Oct 3, 2026, Quantum-Si (QSI) is trading at $1.49 in the after-hours session, down -$0.06 (-3.87%) from the regular market close of $1.55. After-hours prices reflect trading activity that occurs after the market closes at 4:00 PM ET.

Quantum-Si (QSI) is currently trading down in the after-hours session, with a price of $1.49, which is -$0.06 (-3.87%) lower than the regular close of $1.55. After-hours movement shows how the stock is performing outside of normal trading hours.

In the latest after-hours session, Quantum-Si (QSI) has traded between a low of $1.47 and a high of $1.55. These prices reflect extended-hours activity after the regular session ends.

After-hours trading for Quantum-Si (QSI) runs from 4:00 PM to 8:00 PM ET. On Public, eligible stocks can continue trading overnight as part of 24/5 trading, available from Sunday at 8:00 PM ET through Friday at 8:00 PM ET.

You can trade Quantum-Si (QSI) after hours through brokerages that offer extended-hours trading, including Public. Public offers 24/5 trading for eligible stocks from Sunday at 8:00 PM ET through Friday at 8:00 PM ET. Get started with a Public brokerage account to trade QSI.

Quantum-Si (QSI)

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