24/5 Trading

What is 24/5 Trading (Overnight Trading)?

Overnight Trading extends market hours to provide a 24-hour, 5-day-a-week trading experience for all NMS securities. The overnight session operates from 8:00 PM ET Sunday to 4:00 AM ET Friday, bridging the gap between one day's post-market session and the next day's pre-market session.

How does the overnight trading session work?

Overnight trade executions and market data are facilitated by the Blue Ocean Alternative Trading System (BOATS). As an Alternative Trading System (ATS), BOATS operates an independent overnight trading session outside of traditional stock exchanges.

What are the hours for the 24/5 trading sessions?

The trading sessions are structured as follows, from Sunday evening to Friday evening:

Overnight Session: 8:00 PM - 4:00 AM ET (technically occurs on the evening before the trade date)
Pre-Market Session: 4:00 AM – 9:30 AM ET
Regular Market Session: 9:30 AM - 4:00 PM ET
After-Hours Session: 4:00 PM - 8:00 PM ET

The overnight session follows the NYSE holiday calendar. For example, if there is a market holiday on a Friday, the overnight session will not run on Thursday evening. However, the overnight session runs for a full 8 hours on market half-days.

How can I enable overnight trading?

Please contact your Customer Success Manager for details on pricing and the steps required to enable overnight trading for your account.

How can I access market data for the overnight session?

We offer a high-accuracy indicative data feed through our partnership with Blue Ocean, available for a monthly fee. Please contact our sales team for pricing details.

What is included in the overnight market data feed?

The market data feed provides access to:

Indicative Real-time Quotes: Real-time bid and ask prices that are indicative of the market.
Indicative Trades: Trade data that is delayed by 15 minutes and adjusted to fit within the real-time bid-ask spread.

What securities are available for overnight trading?

All National Market System (NMS) securities are available for trading during the overnight session. Assets tradable in the overnight session can be identified via the overnight_tradable attribute in the Assets API. The list may be limited due to compliance or risk procedures, and the best way to validate the available securities is by using our Assets API as outlined above. OTC securities are not part of the NMS and are therefore not available.

What order types and time-in-force (TIF) options are supported?

Order Type: Only limit orders are supported during the overnight session.
Time-in-Force (TIF): The only TIF currently supported is day. day orders placed during the overnight session will remain active through the regular and after-hours sessions of the upcoming trading day. If unfilled, the order is canceled at 8:00 PM ET. Support for GTC (Good-Til-Canceled) orders is planned for a future release.

Is fractional share trading supported?

Yes, fractional share trading is supported during the overnight session and functions the same way as it does during other extended-hours sessions.

Are there restrictions on margin or buying power during the overnight session?

Yes. Day Trading Buying Power (DTBP) does not apply to the overnight session. This means 2x multiplier is the max margin buying power for overnight session trades. If an account uses DTBP for an order during the post market session, the order might be rejected (at 8 PM ET) due to insufficient buying power (if reg_t or non-DT buying power is insufficient).

How does overnight trading impact Pattern Day Trader (PDT) rules?

A day trade is defined as buying and selling the same security on the same calendar day. Trades executed during the overnight session are assigned a trade date based on when they occur:

Trades between 8:00 PM and 11:59 PM ET are assigned the next day's trade date (T+1).
Trades between 12:00 AM and 4:00 AM ET are assigned the current day's trade date (T).

Therefore, a position opened during the overnight session and closed during the regular hours of the same assigned trade date would count as a day trade.

What happens to an order that is not filled during the overnight session?

If your day order is not filled during the overnight session, it will automatically carry over into the pre-market, regular, and after-hours sessions for that trade date. It remains an active order until it is executed or the market closes at 8:00 PM ET.

How does trade settlement work for overnight trades?

The overnight session marks the beginning of a new trading day. Trades are assigned a date based on their execution time and settle on a T+1 basis from that date.

Example: A trade executed at 9:00 PM ET on a Monday is assigned a trade date of Tuesday and will settle on Wednesday (T+1).

How do corporate actions affect overnight trading?

A security may be halted from trading during the overnight session while a pending corporate action is being processed. Furthermore, due to the way trade dates are assigned, purchasing a stock during the overnight session on its ex-dividend date will not entitle you to that stock's dividend.

What happens when a security is halted during the overnight session?

If an asset is halted overnight (e.g., due to a corporate action or pending news), the halt typically persists for the entire session. Orders submitted for a halted security will be accepted by the system with a status of accepted but will be held in a pending state. This ensures your order can be executed as soon as the halt is lifted and trading resumes in the next session.

What API changes are required to support overnight trading?

Integration requires awareness of two new boolean attributes in the Assets API endpoint:

overnight_tradable: Indicates if the asset is eligible for trading in the overnight session.
overnight_halted: Indicates if an overnight_tradable asset is currently halted.

Additionally, a new overnight feed name has been introduced for the Market Data API.

How can I identify which assets are tradable overnight via the API?

You can identify eligible assets by calling the v1/assets endpoint and filtering for assets where the overnight_tradable attribute is true.

When is the best time to sync the list of overnight-tradable assets?

We begin syncing our list of tradable assets at 7:05 PM ET and run updates every 10 minutes until 7:45 PM ET. For the most up-to-date list, we recommend syncing your asset list between 7:45 PM and 8:00 PM ET, with 7:55 PM ET being the ideal time.

Disclosures

The content of this article is for general information only and is believed to be accurate as of the posting date, but may be subject to change. Alpaca does not provide investment, tax, or legal advice. Please consult your own independent advisor as to any investment, tax, or legal statements made herein.

Orders placed outside regular trading hours (9:30 a.m. – 4:00 p.m. ET) may experience price fluctuations, partial executions, or delays due to lower liquidity and higher volatility.

Orders not designated for extended hours execution will be queued for the next trading session.

Additionally, fractional trading may be limited during extended hours. For more details, please review Alpaca Extended Hours & Overnight Trading Risk Disclosure.

Fractional share trading allows a customer to buy and sell fractional share quantities and dollar amounts of certain securities. Fractional share trading presents unique risks and is subject to particular limitations that you should be aware of before engaging in such activity. See Alpaca Customer Agreement at Alpaca - Disclosures and Agreements for more details.

Margin trading involves significant risk and is not suitable for all investors. Before considering a margin loan, it is crucial that you carefully consider how borrowing fits with your investment objectives and risk tolerance.

When trading on margin, you assume higher market risk, and potential losses can exceed the collateral value in your account. Alpaca may sell any securities in your account, without prior notice, to satisfy a margin call. Alpaca may also change its “house” maintenance margin requirements at any time without advance written notice. You are not entitled to an extension of time on a margin call. Please review the Firm’s Margin Disclosure Statement before investing.

All investments involve risk, and the past performance of a security, or financial product does not guarantee future results or returns. There is no guarantee that any investment strategy will achieve its objectives. Please note that diversification does not ensure a profit, or protect against loss. There is always the potential of losing money when you invest in securities, or other financial products. Investors should consider their investment objectives and risks carefully before investing.

Securities brokerage services are provided by Alpaca Securities LLC ("Alpaca Securities"), member FINRA/SIPC, a wholly-owned subsidiary of AlpacaDB, Inc. Technology and services are offered by AlpacaDB, Inc.

Cryptocurrency services are made available by Alpaca Crypto LLC ("Alpaca Crypto"), a FinCEN registered money services business (NMLS # 2160858), and a wholly-owned subsidiary of AlpacaDB, Inc. Alpaca Crypto is not a member of SIPC or FINRA. Cryptocurrencies are not stocks and your cryptocurrency investments are not protected by either FDIC or SIPC. Please see the Disclosure Library for more information.

This is not an offer, solicitation of an offer, or advice to buy or sell securities or cryptocurrencies or open a brokerage account or cryptocurrency account in any jurisdiction where Alpaca Securities or Alpaca Crypto, respectively, are not registered or licensed, as applicable.