Pre-market and after-hours trading: US extended hours, CFD availability and liquidity

Pre-market and after-hours trading are the extended sessions in which US shares change hands outside the regular 09:30 to 16:00 New York session. On major US venues, pre-market trading can begin as early as 04:00 and after-hours trading can continue until 20:00 New York time, although many brokers offer shorter windows. Fewer people trade in these sessions, so spreads are wider and prices can move sharply on small volumes.

For CFD traders the practical question is whether you can trade at all. Most share CFDs follow the regular session only, so news released after the close can move the underlying share in extended hours while your CFD stays shut until the next open. US index CFDs are different: many are priced from futures and trade nearly 24 hours on weekdays.

The US trading day

The regular session

The New York Stock Exchange and Nasdaq run their regular session from 09:30 to 16:00 New York time, Monday to Friday, excluding exchange holidays. The session begins with an opening auction and ends with a closing auction that sets the official closing price used for index calculations, fund valuations and most daily charts. Our guide to how stock markets work explains the auction process.

Extended sessions

• Pre-market: from as early as 04:00 to 09:30 New York time on major venues such as Nasdaq.
• After-hours: from 16:00 to as late as 20:00 New York time.

Individual brokers choose which parts of these windows they offer. Some start pre-market at 07:00 or 08:00, for example. A few brokers and alternative trading systems also run overnight sessions in selected shares, and exchanges have announced plans to extend trading towards 24 hours on weekdays, subject to regulatory approval and industry infrastructure. Those arrangements are changing, so check what your own broker or provider offers rather than relying on a general rule.

In UK and European time

New York is normally five hours behind London and six hours behind Central European Time.

• Pre-market from 04:00 New York is 09:00 London and 10:00 CET.
• The regular session from 09:30 to 16:00 New York is 14:30 to 21:00 London and 15:30 to 22:00 CET.
• After-hours until 20:00 New York is 01:00 London and 02:00 CET.

For a few weeks each year the gap is four hours instead of five, because the US and Europe change their clocks on different dates. The US moves to summer time on the second Sunday in March and back on the first Sunday in November; the UK and EU change on the last Sunday in March and the last Sunday in October. During those mismatch weeks, the US regular session runs from 13:30 to 20:00 London. Our market hours tool shows the sessions in your own time zone.

Why extended hours exist

Much important company news is released deliberately outside the regular session. Most US companies publish quarterly results either before the open or after the close, as our guide to earnings season explains. Mergers, profit warnings and regulatory decisions are often announced outside regular hours too. Extended sessions let investors react to that news before the next regular open, and let people in other time zones trade US shares during their own day.

How extended-hours trading differs

Liquidity

Far fewer participants trade in extended hours. Many institutional investors and market makers are less active, and the bulk of daily volume in most shares happens during the regular session, much of it near the open and close. With fewer orders in the book, each trade can move the price more. The liquidity glossary entry covers why that matters.

Spreads

Thin order books mean wider bid-ask spreads. A large, heavily traded share whose spread is a cent or two during the day might show a spread many times wider in pre-market, and smaller shares can show very wide spreads or no quotes at all.

Volatility and unreliable prices

Prices in extended hours can jump around, especially just after a news release, and an individual trade can print well away from the prices either side of it. Extended-hours prices are a useful sign of the market's first reaction, but they are not a reliable guide to where the share will open. A share down 10% after hours on an earnings release might open down 5% or down 15% once the conference call is over and the full market participates.

Order types

Many brokers accept only limit orders in extended sessions, to protect clients from being filled at extreme prices in a thin market. Stop orders and market orders may be held until the regular session or rejected. Orders placed for the regular session do not usually execute in extended hours unless you specify that they should.

Prices that do not count

The official daily close is set at 16:00 by the closing auction. After-hours trades do not change that close, which is why a share's daily chart can show a gap at the next open: the "gap" partly reflects movement that already happened in extended hours.

Worked example: the cost of trading in a thin session

Illustrative numbers only. A share trades at about 100.00. During the regular session its spread is 0.02; in pre-market it is 0.30.

• Spread cost on 200 shares in the regular session: 200 × 0.02 = 4.
• Spread cost on 200 shares in pre-market: 200 × 0.30 = 60.

The same trade costs 15 times as much in spread alone, before any slippage from a thin order book. For a trader whose expected edge per trade is small, that difference can be decisive. Our guide to why spreads widen explains the same effect in currency markets.

Share CFDs and extended hours

What most providers do

A share CFD tracks the underlying share price, and most providers quote share CFDs only during the regular exchange session. If a US company reports after the close, the underlying share may move sharply in after-hours trading, but your CFD position cannot be closed or adjusted until the regular session opens the next day, at whatever price it opens. The stock CFDs versus real shares guide compares the two ways of trading shares in more detail.

Extended-hours share CFDs

Some providers offer extended-hours trading on a selection of large US shares, sometimes covering pre-market and after-hours and sometimes only part of them. Where this is available, expect:

• Wider spreads than in the regular session.
• A limited list of eligible shares.
• Different order rules, for example limits only, or stops that do not trigger until the regular session.
• Prices that are based on thin underlying trading, so the CFD can move sharply on small volumes.

The trading hours for each instrument appear in the provider's contract specifications. Check them rather than assuming.

Worked example: news after the close

Illustrative numbers only. You hold a long share CFD of 80 shares that closed at 100.00. You have a stop loss at 95.00, so your planned risk from the close is 80 × 5.00 = 400.

After the close, the company cuts its full-year outlook. The underlying share trades at 91.00 in after-hours. Your CFD follows regular hours only, so you cannot act. The next morning pre-market trading ranges between 90.00 and 93.00, and the share opens in the regular session at 92.50.

• Your stop at 95.00 is triggered at the open and filled at about 92.50.
• Loss from the previous close: 80 × (100.00 − 92.50) = 80 × 7.50 = 600.

That is 1.5 times the planned 400. The after-hours price of 91.00 was never available to you, and neither was a fill at your stop level. The gap risk guide covers how stops behave in gaps, and a guaranteed stop loss, where offered, is the only order type that removes that gap risk, for a premium.

Index CFDs and futures

US index CFDs are often priced from index futures, which trade on CME Globex almost 24 hours a day from Sunday evening to Friday evening New York time, with a short daily break. That means index CFDs on the S&P 500, Nasdaq 100 or Dow can usually be traded while the cash market is closed, including during US pre-market and after-hours sessions and the European and Asian day. Our guide to index futures versus index CFDs explains the difference between cash and futures-based contracts.

This has two consequences:

• Index CFDs react first. When a large company such as a major index constituent reports after the close, index CFDs can move immediately, while single-share CFDs stay closed.
• Overnight liquidity is still thinner. Index futures are liquid by most standards, but spreads on index CFDs are often wider outside the US cash session, especially in the hours around the daily break.

The guide to trading index CFDs covers contract sizes and costs, and our Nasdaq 100 trading guide covers one of the indices most sensitive to after-hours earnings from large technology companies.

European and UK shares

Most European exchanges do not run US-style retail extended sessions. The London Stock Exchange's main session runs from 08:00 to 16:30 London time, with a closing auction, and most UK and European share CFDs follow the regular session of their home exchange. Company announcements in the UK are typically released through regulatory news services at 07:00 London time, before the open, so the reaction appears at the opening auction. Some providers offer CFDs on selected European shares at other times, but this is less common than for US shares.

Trading halts

Extended-hours trading can also be affected by halts. If an exchange halts a share pending news, trading stops in all sessions until the halt is lifted. US markets also have marketwide circuit breakers that apply during the regular session. Our guide to trading halts and circuit breakers covers both.

A practical checklist for extended hours

Before relying on extended-hours prices or trading in them, it helps to run through a few questions:

1. Which sessions does my provider offer for this instrument? Check the contract specification for the share or index CFD, including any daily breaks.
2. Is there scheduled news? Look up earnings dates and other known announcements for the shares you hold, and decide in advance whether to hold through them.
3. What order types are accepted? Confirm whether stops, limits and market orders work outside the regular session, or are held until the open.
4. How wide is the spread right now? Compare it with the usual regular-session spread before placing an order.
5. What happens if the share gaps through my stop? Work out the loss at a plausible gap, not just at the stop level, and size accordingly. The instruments position size calculator helps with the arithmetic.

None of these steps removes the risk of trading leveraged products, and most retail CFD accounts lose money, as our guide to why most retail CFD traders lose explains. They do make it less likely that an extended-hours move catches you by surprise.

Common mistakes

• Treating after-hours prices as the next open. Extended-hours prices are an early reaction from a thin market and can change materially by the regular open.
• Assuming your CFD trades when the share does. Most share CFDs follow the regular session only.
• Placing market orders in thin sessions. Where extended-hours trading is available, a market order can be filled far from the last price; many brokers allow only limits for this reason.
• Relying on a stop to work outside regular hours. Stops may not trigger until the regular session, and then only at the first available price.
• Forgetting the clock changes. For a few weeks in March and in October to November, the US session starts an hour earlier in UK and European time.
• Ignoring the cost of wider spreads. Small edges can disappear in extended-hours spreads.

Frequently asked questions

What are the US pre-market and after-hours trading times?

On major US venues, pre-market trading can begin as early as 04:00 and after-hours trading can run until 20:00 New York time, around a regular session of 09:30 to 16:00. Individual brokers often offer narrower windows, so check yours.

Can I trade share CFDs before the market opens?

Usually not. Most share CFDs follow the exchange's regular session only. Some providers offer extended-hours trading on selected US shares, with wider spreads and different order rules. Check the trading hours in your provider's contract specifications.

Why are spreads wider in pre-market and after-hours trading?

Because fewer buyers and sellers are active, order books are thin, and market makers take more risk quoting prices. Wider spreads compensate for that risk and make each trade more expensive.

Does after-hours trading affect the next day's open?

It often gives an early indication, but the official open is set by the opening auction, which brings in the full market. The open can be above or below the last after-hours price, sometimes by a wide margin.

Can I trade US index CFDs at night?

Usually yes. Many US index CFDs are priced from futures that trade almost 24 hours on weekdays, so they are often available outside the US cash session. Spreads can be wider at night, and there is typically a short daily break.

Do stop losses work in extended hours?

It depends on the broker or provider. Many do not trigger stops in extended sessions, so they wait until the regular session opens, when the order is filled at the first available price. That can be well beyond your stop level after a large overnight move.