When does a 0 dte SPX stop trading? I have a contract that exp aug 18 and I thought it closed at 4pm est; but my bid and ask on that contract still showed moving after 4pm. Can you confirm the time SPX closes trading on a contract that expires on the day. thanks ps....its still showing trading...4:20 I sold some 4255 puts - wouldn't they be worthless now since SPX is 4284?
When trading Odte SPX options today i had the same question. Can´t answer the question yet. I think i have heard trading ends at 04:15 pm, but i´m not quite sure.
I was told SPY was 415pm and SPX 0 dte was 4pm est. My SPX puts is still showing movement on the bid and ask even tho it expires today Aug 18. Wtf? Even the SPX site says 4pm est trade stops on 0 dte.
Looks like you traded SPX AM options that settle based on tomorrow mornings opening. They trade until 415 pm et (and on the curb session for an additional 45 minutes). The SPXW options are the ones expiring based on the 4pm SPX closing settlement price. They stop trading at 4pm et. Looks like you are using Interactive Brokers. They can be confusing here as they list Aug 18 for both the AM SPX contracts settling tomorrow and for the ones settling this afternoon. You would have to know to look for SPX and SPXW. Edit to add, if you are trading IB, you can still trade these on the curb session until 5pm et. IB is one of the few brokers that allows trading in this session.
Thank you!! So at what time exactly will I not be screwed on this position (with my luck i get a black swan event )? 5pm est? or will i have to wait until mkt price opens on fri aug 19?? I did a credit put position 4255 - so SPX needs to stay under 4255 until when??
If you don't close you position on the curb session before it stops trading at 5pm et, you will be at risk of wherever the SPX opening mark (SET) is tomorrow morning. That value will be listed here tomorrow Index Settlement Values (cboe.com)