TOS vs TWS discrepancy In P&L's between two platforms

[ClearCut]

Hi I noticed the P&L's are different in TOS are different in Vertical Debit Spreads.  The TOS does make sense to me but the TWS doesn't

eg below, please note pics attached

TOS

The Max profit  = 545 ,  $10 spread Less  Debit paid 455+commissions  . . . . makes sense

TWS

Max Profit = 425 ???? doesn't make sense because debit paid is also 455+similar comissions.

Shouldn't the P&L be the same or similar in both cases.  I know commissions are slightly different but I don't think they impact the overall calculation that much.

[betaboy3000]

I'll take a stab....

In my experience TWS uses a pessimistic ASK price + a pessimistic commission to give you a pessimistic chart. It can't tell you the exact commissions at this point because it depends on the exchanges you get filled on. The higher the spreads the more it gets wonky.

I always calculate my max profit and max loss AFTER the trade is done. The performance chart just gives you an idea of the shape of the curve. You should use it to make sure you got the buy/sell +/- right.

In this case for a bull debit spread your max loss would be the price of the spread, say 4.55.

Your max gain would be the spread width - the cost of the spread, or 10-4.55 = 5.45.

 

[ClearCut]

Thanks for the reply.  Yeah I was thinking the same thing, but if I did a limit order at 4.55,s  shouldn't it state a correct max return of 5.45  (maybe + or -  few bucks for commissions)?

It's just basic math right?

[betaboy3000]

8 minutes ago, ClearCut said:

Thanks for the reply.  Yeah I was thinking the same thing, but if I did a limit order at 4.55,s  shouldn't it state a correct max return of 5.45  (maybe + or -  few bucks for commissions)?

It's just basic math right?

It doesn't actually consider what your order was, just the Bid/Ask.

[betaboy3000]

I should also say that although the picture is more pessimistic, you'll probably get slightly a better price including commission with IB compared to TOS for a trade like this.  

[ClearCut]

Great Thanks.  Hopefully the p&l gets updated after entering the trade.

[betaboy3000]

53 minutes ago, ClearCut said:

Great Thanks.  Hopefully the p&l gets updated after entering the trade.

It doesn't.  It will still base it on the current bid/ask.