Trading Sessions and Costs: Hours, Fees and Slippage

Before you read: Order Types Explained: Market, Limit, Stop and Bracket

What you will learn

• How regular and extended trading hours differ, for stocks and for many futures.
• The main costs of trading: commissions, exchange and clearing fees, regulatory fees, data fees, spread and slippage.
• Why taxes matter at a high level, and why the details belong with a qualified adviser.

When is a market open?

Is the price at 3 a.m. as meaningful as the price at midday?

Markets keep schedules, and the schedule shapes what you see on a chart.

US stocks have a regular session of 9:30 a.m. to 4:00 p.m. Eastern time on trading days. Exchanges publish a holiday calendar that includes full closures and a few scheduled early closes. Many brokers also offer extended hours: a pre-market session before the open and an after-hours session after the close. Extended sessions usually have fewer participants, wider spreads and thinner order books, and some order types may not be accepted in them.

Many futures trade for most of the day and night on electronic platforms, with a short daily maintenance break and a weekend close. Exchanges publish the exact hours for each product, and hours shift around holidays. Many traders still separate the regular trading hours (often aligned with the related cash market) from the overnight or electronic session, because activity, volume and spreads usually differ between them.

Sessions and costs diagram

Illustrative diagram constructed for teaching. Not real market data.

The diagram shows a constructed 24-hour timeline showing a regular session, extended sessions and a daily break, beside a cost stack that separates explicit and implicit costs. The hours are simplified for teaching, and no real fees are implied. Check the exchange for current hours. It is constructed for teaching and is not real market data.

Why do session boundaries matter?

If you change the session your chart uses, does the chart change?

Session settings decide where a daily bar starts and ends, what counts as the “open” and the “close”, how a session VWAP resets, and whether a gap appears. The same market can show a gap on a regular-hours chart and no gap at all on a chart that includes the overnight session. When you compare notes with someone, check that you are using the same session definition. The idea returns in opening types and day types and VWAP.

What does a trade actually cost?

If a trade breaks even on price, did it cost nothing?

Costs come in two groups: those you see on a statement and those you only see in your fills.

Explicit costs appear on statements:

• Commission: what the broker charges per trade, per share or per contract. Some brokers advertise zero commission on stocks; they may be paid in other ways, such as payment for order flow or wider fills.
• Exchange fees: charged by the exchange for each contract or share traded. They vary by product, by membership status and sometimes by whether your order added or removed liquidity.
• Clearing fees: charged for clearing and settling the trade.
• Regulatory fees: small per-transaction charges collected for regulators or self-regulatory bodies, depending on the market.
• Platform and data fees: monthly charges for charting software or for real-time exchange data. Exchanges often charge different rates to professional and non-professional subscribers.

Implicit costs come from the market itself:

• Spread: trading immediately means buying at the ask or selling at the bid, so a round trip at market crosses the spread twice in effect.
• Slippage: fills that differ from the expected price, which order types and execution explains. Slippage is usually larger in thin or fast markets.

How do small costs add up?

How many trades does it take for a small cost to become a large one?

Illustrative arithmetic only, not a recommendation. Imagine a fictional futures contract where one tick is worth $5, and suppose each round trip (in and out) costs:

• $4 in commission and fees combined, and
• one tick of spread and slippage combined, or $5.

That is $9 per round trip per contract. Over 100 round trips the costs come to $900, whatever the trades did on price. Doubling the number of trades doubles the cost.

The point of the arithmetic is not the size of any number, which is made up, but the shape: costs are certain, and they repeat with every trade. Results that look positive before costs can turn negative after them, which is why honest testing includes realistic costs.

The example uses a futures contract, which is a leveraged product. Leverage can cause losses larger than the amount invested.

What about taxes?

Who decides how a trading gain or loss is taxed?

Gains and losses from trading are usually taxable, and the treatment depends on where you live, what you traded, how long you held it, the type of account and your own circumstances. Some countries treat certain futures or options differently from stocks. Rules change. Accurate records of every trade and cost (for example, a trading journal) make those questions easier to answer, and a qualified tax professional is the person to ask about an individual situation.

What this does not tell you about sessions and costs

• The current hours, fees or margin for any product; those come from the exchange and the broker.
• Which broker or data package suits anyone.
• How any tax rule applies to you.
• Whether any trading activity will cover its costs.

Watch the lesson explained

Check yourself

Reflect on these; there is no score.

1. Name three costs that appear on a statement and two that only show up in your fills. Hint: explicit versus implicit.
2. Why might a chart that includes the overnight session show no gap where a regular-hours chart does? Hint: what fills the time between the two sessions.
3. In the fictional example, what would 250 round trips cost? Hint: cost per round trip × number of trips.
4. Why would someone keep a record of fees even if they are small? Hint: they repeat, and tax records need them.

Last reviewed November 8, 2026. Spotted a mistake? Report an error.