Hello --- I'm papertrading options with a TOS account. Exited a position I had on SPX today at .05 off the mid. I know papertrading doesn't give completely realistic fills vis a vis mid and b/a spread, particularly if the b/a spread is wide. I'm going to adjust this trade in my trade log with an estimation of what a more realistic fill might have been. Sort of losing myself some money on paper, you might say With mid at .65 and nat 1.35, I was filled at .70. Those of you who are trading real $, is this realistic with this much room between the two?
Honestly a common fill you might see over time is halfway between the mid and the bid or halfway between the mid and the ask. Of course there will be times you will be filled just off the mid but what happens usually is the market moves and the mid shifts and your order is now somewhere in between the mid and the ask to buy and you get hit. To be consistent for papertrading I would go with that halfway rule I mentioned above to make it more realistic.