The clock you trade against matters as much as the setup you take. Two traders running the same strategy can post opposite results for one reason only: one worked a liquid session and the other fought a thin one.
For an evaluation, that choice isn’t cosmetic — it decides how honest your fills are and how exposed your drawdown gets.
What RTH and Globex actually cover
Futures trade nearly around the clock, but not all of those hours are the same market.
- RTH (Regular Trading Hours) is the “cash session.” For US equity index futures it’s roughly 9:30 a.m. to 4:00 p.m. Eastern, the window that overlaps the stock market. It’s where the day’s headline range, volume, and reference levels get built.
- Globex is CME’s electronic session, running almost continuously — Sunday evening through Friday afternoon Eastern, with a short daily maintenance halt. It covers the Asian and European hours and the US pre-market.
Most traders’ charts, indicators, and prior-day levels are drawn from the RTH range specifically, which is one reason RTH behavior looks cleaner and more textbook. Exact hours vary by product — index, energy, metals, and agriculture all differ — so confirm the session for the contract you actually trade.
Liquidity and spread differences by session
Liquidity is the quiet variable that decides how much your fills cost you.
- During RTH, the order book is deep, the bid–ask spread on liquid contracts sits at a single tick, and size gets absorbed without moving price much.
- During the overnight Globex hours — especially the lull between the US close and the London open — the book thins out. Spreads widen, and the same size that barely registered at midday can jump price several ticks.
That difference compounds. A strategy that’s marginally profitable on paper can turn negative purely on worse fills and wider spreads in a thin session. The edge was real; the execution ate it.
Why thin overnight markets threaten your drawdown
For a funded account, thin liquidity isn’t just a cost — it’s a tail risk aimed straight at your trailing drawdown.
- Slippage on stops. In a thin book, a stop becomes a market order that fills at the next available price, which overnight can be well past your level. Your planned loss and your actual loss diverge exactly when you can least afford it.
- Gap risk. A headline in the Asian session can move a market before you’re awake, with too few resting orders to cushion the move.
- False breaks. Low volume lets price wander through levels that would have held in RTH, triggering stops a liquid session never would.
Because a trailing floor follows your equity and never forgives, one bad overnight fill can undo a week of careful trading. If that mechanic is fuzzy, start with what a trailing drawdown is. This is also where a hard, broker-side max-loss limit matters most — Shibiki can hold that ceiling even while you sleep, so a thin-market spike can’t drag a position past your floor before you react.
Matching your strategy to the right session
There’s no universally better session — only the one that fits your edge.
- Momentum, breakout, and opening-range strategies generally want RTH: real volume, real participation, follow-through you can trust.
- Mean-reversion and range strategies sometimes prefer the quieter tape — but only in the genuinely liquid overnight windows, such as the London hours for many products, not the dead zones.
- News-driven approaches live and die by the release schedule more than by the session label.
The point is to choose deliberately. If your journal shows winners clustering in the US morning while your overnight trades bleed on slippage, that’s a session problem, not a strategy problem. Shibiki auto-journals every fill with its timestamp and surfaces live edge health with a Wilson confidence interval per setup, so you can tell whether your overnight results are genuinely positive or a small, noisy sample flattering a session you shouldn’t be trading.
Session rules some prop firms enforce
Beyond your own preference, your firm may make the choice for you.
- Some evaluations require positions flat before a daily cutoff, effectively banning overnight holds.
- Others restrict or forbid holding through the weekend or through high-impact news.
- A few limit trading during specific low-liquidity windows outright.
These rules exist precisely because thin sessions and gap risk are how accounts blow up — the firm is protecting its capital and, incidentally, yours. Cutoff times and policies differ by firm and change often, so confirm the current version with your provider; the pages for firms like Topstep and Take Profit Trader are the place to check specifics rather than trusting a forum post. If you run several funded accounts, Shibiki can copy your trades across them, so a flat-by-cutoff discipline applies everywhere at once instead of account by account.
Related: Topstep · Trailing drawdown explained · Take Profit Trader