Buy 1 ES @ $2700.125... $135,006.25
Buy 500 SPY@ $270.01... $135,005.00
Isn't 0.25 the smallest tick on ES?
Buy 1 ES @ 2700.25... $135,012.50
But there is more slippage in the SPY...
1. The time it takes to execute... that's not just "exchange" time.. it's also the time it takes you to decide to make the play, enter the order on your platform, and get it off to the broker for execution. Of course the market may move in your favor during that time.
In the ES, you can "instantly reverse"... long to short, and vice-versa.. with one click of the mouse.
Why would ES take less time to execute or SPY not be able to instantly reverse?
2. Settlement. Once you sell, you can't do anything with that money until settlement. Of course you can/may use margin, but pay interest to the broker for doing so. Otherwise, you're locked out of the marketplace for 2 days. Of course you can play only a portion of your capital to have cleared funds for the next play while waiting for settlement. For comparison purposes I'm assuming you're committing ALL of your capital and don't have that option.
When you day trade stocks/ETFs on margin there is no interest payment. But now that you mention it, it's true that the futures likely have a significantly lower cost of carry than the ETF for long holding periods. Depending on your broker, it might take as little as one overnight hold to breakeven or come out ahead with the futures (wow)!
Besides, futures are 1256 contracts and get a bit of a favorable tax treatment... though that's not a slippage issue.
Interesting, I wasn't aware of that. That would be very important if you are based in the US.
I think part of this a kind of network effect.. liquidity begets liquidity. For example why does SPY have 30x the volume of VOO even though VOO has lower fees. But the interest rate, tax treatment and larger minimum display size are probably big factors too.The daily $$ handle on the ES is about 10x that of the SPY. I'm sure that if there were an overall advantage to the SPY, it would be the one with the bigger handle.