Half Days and Holiday Shortened Sessions

Almost everyone trades a half day as if it were a normal session that happens to finish early, and that is the error. An early close does not remove the last three hours, it compresses everything following the opening range into a shorter window, so the part of the day that usually has time to develop no longer does. The calendar breakdown sitting on orb trading routine richiebranson lists these sessions separately from full ones for that reason, since a routine written around a normal close silently assumes hours that do not exist.

What Actually Changes

Participation drops, and it drops unevenly. The opening bell often looks normal, because the traders who are present are the ones who were always going to trade the open. The thinning shows up later, in the hour after the range, exactly where a breakout needs continuation to pay. A move that would carry on an ordinary Tuesday stalls at eleven o'clock on a half day.

The Compression Problem

A trade taken at the usual time has less room to work before the closing bell. Where the exit rule is time based, that rule has to be rewritten for the day rather than applied unchanged. Flat by a fixed clock time on a normal session might mean flat two hours after entry. On a one o'clock close it might mean flat twenty minutes after entry, which is a different strategy wearing the same name.

Adjust Before the Open, Not During

The adjustments are known in advance because the calendar is published months ahead. Decide the night before whether the session is traded at all, what the modified exit time is, and whether the position size changes. Working it out at 11:40 while holding a position is how a half day produces its characteristic mistake, which is holding too long into a market that has already gone home.

The Day Before and the Day After

The session before a holiday is frequently worse than the half day itself, since volume drains without any announcement. The session after tends to be closer to normal but not identical, particularly on the first open following a long weekend, where the overnight session has absorbed several days of news.

Both are worth flagging in the record so the results can be separated later. A handful of holiday sessions mixed into a quarter of ordinary ones distorts the average and hides the fact that they behave differently.

The Case for Skipping

Skipping a half day costs one session out of roughly two hundred and fifty, and removes a set of conditions the strategy was never measured on. Traders who keep the record separately usually find the answer already sitting in their own numbers, which is a better basis for the decision than a general opinion that holiday sessions are untradeable. Measure first, then choose, and write the choice down so it is not re-argued every December.