May turned out to be CBOE’s second highest volume month during the Exchange’s Extended Trading Hours options session.  Average daily volume during ETH in May was 11,763 contracts per day, surpassed only by November’s 14,118 contracts per day.  However, May’s volume was much more consistent, as opposed to the November volume which was highly concentrated in a single trading day in the wake of the U.S. Presidential election.  More market participants appear to now be relying on the ETH session on a regular basis, rather than simply using the session to react to global events during non-U.S. hours.

A key driver for the increased ETH volume has been increased liquidity support from the London dealer community.

CBOE’s ETH option session offers trading of SPX and VIX options from 8:00 a.m. London time until 2:15 p.m. London time.  More information about ETH can be found here at