Yes— TastyTrades is the cheaper ‘most of the times’: You pay $1.00 to open and $0.00 to close which amounts to $0.50 per side (a leg) . However on TOS, you pay $0.65 per leg unless you closed a leg for less than $0.05, in which case you pay $0.00 — and this would be cheaper in comparison ($0.325)