Quote from tomk96:
what is it that you want to know? the markets are the markets, regardless of how you want to calc IV.
if something is 2.00-2.20, does it matter whether you are calculating it on fri, sat, sun, or monday even if it's only noon on the friday of a 3 day weekend?
There is no decay or volatility adjustment for the weekend. The prices and vol are already priced in at the close Friday for the next weekâs open. So if it closed at 2.10 Friday then the market makers expect they will open it at 2.10 the next week, but the vol isnât really 40 on Friday, it is 50 in your example because they are already running Mondayâs date for their models.Quote from IV_Trader:
If the markets are at 2.10 mid with 40 vols on Friday close, what is the guesstimate/model for Monday open? Is it :
Still 2.10 (hence, the vols print= 50) OR
Vola stays at 40 (hence, the mid at 1.80)??
Quote from opt789:
There is no decay or volatility adjustment for the weekend. The prices and vol are already priced in at the close Friday for the next week¡¦s open. So if it closed at 2.10 Friday then the market makers expect they will open it at 2.10 the next week, but the vol isn¡¦t really 40 on Friday, it is 50 in your example because they are already running Monday¡¦s date for their models.
That part is pretty simple, but you should be more concerned about gamma with a week to go until expiration of the option, not so much about vol.

From my experience the exact specifics of when the market makers start to price in the weekend varies on the underlying, but basically you can think of running time ahead in a smoothed fashion. This will obviously vary if there is news expected at some point, and you can always argue whether the market makers are changing implied vol or running time ahead (it is two sides of the same coin). If you have priced in Monday morning, or Sunday night for futures options, by the close Friday then work backwards, so by Wednesdayâs close they may start slowly running time ahead. I have watched markets where the whole 7 days are very smoothly run through during the trading week, and others where it is done mostly Thursday and Friday.Quote from IV_Trader:
Thanks opt¡Kunfortunately this part is not pretty simple to me. I am looking for mechanics of pricing in process. If end of Friday = Monday open, then when did the smoothing started?? Friday morning? Day before?
BTW ¡V let the other side of my trade be concerned about gamma risk because I always long options (unless it's a calendar trade)![]()
Quote from opt789:
From my experience the exact specifics of when the market makers start to price in the weekend varies on the underlying, but basically you can think of running time ahead in a smoothed fashion. This will obviously vary if there is news expected at some point, and you can always argue whether the market makers are changing implied vol or running time ahead (it is two sides of the same coin). If you have priced in Monday morning, or Sunday night for futures options, by the close Friday then work backwards, so by Wednesdayâs close they may start slowly running time ahead. I have watched markets where the whole 7 days are very smoothly run through during the trading week, and others where it is done mostly Thursday and Friday.