Interactive Brokers Fees question

[RC.]

When you take liquidity with IB, option contracts often cost around 1usd/contract (ie 2usd for round trip)
I often add liquidity but still have a hard time figuring out how much it will cost me beforehand, sometimes it's negative but other times it costs around 0.70, no matter I use direct routing, smart or smart rebate, I get confused ( I don't have huge experience either, trading from a few to 200 contracts at a clip)

I was looking at TradeKing's fees, and realized they actually would charge me less for the same trade. Ridiculous.

Can I know what you mean by "adding liquidity" and removing it? I thought the whole point of tiered commissions was to remove worrying about that. Anyway, is adding liquidity pretty much selling at the bid?

 

[luisHK]

It's quite the contrary about removing this worry, flat price will do that, removing and adding liquidity costs/rebates appear under the untiered pricing, each exchange has different costs btw.
Selling at the bid would be removing liquidy, you usually pay for that. Adding liquidity is when your order rests on the book,like if you add a sell order at the offer, you usually get paid for that, hence sometimes negative commissions with IB.
Besides yes, if you only trade the US markets and don't borrow too much from your broker, especially if you trade large lots, there are cheaper retail brokers than IB
Also again, I have a harder time understanding teh untiered pricing of options than of shares, for instance when adding liquidity through BATS (possibly via smart) I might get -2usd commission on 100contracts but 70usd on 200. I've been puzzled a few times.