RTH (regular trading hours)

RTH (regular trading hours) is the part of a futures session that overlaps the cash market of the underlying index, as opposed to the overnight electronic hours. For CME equity index futures it is the window in which most of the day's volume prints and in which cash-referenced levels such as the opening range are usually measured.

Senzoukria · Glossary · Updated September 2026

What RTH refers to

A CME index future trades almost around the clock, but the underlying cash index only prices while the stock exchanges are open. RTH is the slice of the futures session that coincides with that cash window. Everything outside it is the extended or overnight session, usually abbreviated ETH.

The distinction matters because the two windows do not behave alike. Volume, participation and the size resting in the book are usually very different, so a level or a threshold derived during one window rarely transfers cleanly to the other. RTH is also the reference most day-trading conventions assume: the opening range, the initial balance and the daily high and low that most people quote are RTH figures unless stated otherwise.

  • RTH is a subset of the full electronic session, not a separate market.
  • The RTH open is a fixed local time at the exchange, so it stays in the same place across daylight-saving changes in Chicago.
  • Data vendors and platforms may define RTH differently; the boundaries you use should be stated with the chart.

How RTH changes what you read on a footprint

  • Imbalance ratios and minimum-size filters tuned on RTH volume will fire far more often overnight, when a single print is a larger share of the level.
  • A cumulative delta reset at the RTH open tells a different story from one reset at the electronic session open; both are valid, but they are not the same curve.
  • The first RTH bars carry the overnight inventory into the cash open, which is why many traders read the overnight high and low as levels for the RTH session.
  • Volume profiles built on RTH only and on the full session have different points of control; compare like with like.

In Senzoukria

The desktop application anchors every session on the CME electronic open, 17:00 Chicago time. RTH appears as an offset from that anchor rather than as a separate session type: the Overnight High/Low indicator expresses the RTH open as minutes after the session open, with a default that lands on 08:30 Chicago time for CME equity indices, and projects the overnight extremes over the rest of the session.

The Opening Range, Session High/Low and Initial Balance indicators are measured from the source session opening, not from the cash open. The Initial Balance note in the application says explicitly that its window follows the source session opening and is not implicitly an RTH opening range; the same applies to the Opening Range. If you want an RTH-based range, account for the offset yourself rather than assuming it.

Common mistakes

  • Comparing a vendor's RTH-only daily volume with a full-session total and concluding that one feed is wrong.
  • Assuming the RTH open is 09:30 in your own time zone; it is a Chicago or New York time and shifts relative to Europe and Asia twice a year.
  • Reading an overnight breakout with RTH-sized imbalance thresholds.
  • Treating a partially loaded RTH window as a complete opening range.

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Frequently asked questions

When does RTH start and end for ES and NQ?
For CME equity index futures, RTH corresponds to the hours of the US cash equity market, quoted in Chicago or New York time. The exact boundaries, and whether a platform includes the closing auction period, depend on the platform's session template, so check the definition your chart uses rather than assuming a universal one.
Should a cumulative delta reset at the RTH open or at the session open?
Either is defensible as long as the reset point is visible. A reset at the electronic session open counts overnight aggression; a reset at the RTH open isolates the cash-hours flow. Senzoukria's Session CVD resets at the CME session open, and the anchor of the built-in cumulative delta panel can be changed if you want a different reference.
Is RTH the same thing for crypto?
No. Crypto exchanges run continuously with no cash-market overlap, so there is no RTH in the futures sense. Time-of-day patterns exist, but they are conventions chosen by the analyst, not a session defined by the venue.

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