Question 1

Is zero-commission trading actually free?

Accepted Answer

No. Zero commission only removes the per-trade fee a broker charges. You still pay the spread on every entry and exit, you can lose money to slippage, and leveraged or overnight positions can carry financing charges. The headline of free refers to one cost, not all of them.

Question 2

What are the four main costs of a trade?

Accepted Answer

Commission, the spread, slippage, and financing. Commission is the broker fee, the spread is the gap between bid and ask you pay on a round trip, slippage is the gap between the price you expected and the price you got, and financing is the cost of borrowing to hold leveraged or overnight positions.

Question 3

Why do costs matter more for active traders?

Accepted Answer

Every cost is paid per trade, so the more you trade, the more times you pay them. A cost that looks tiny on one trade becomes a large drag across hundreds of trades, which is why short-term strategies have to clear a much higher bar to come out ahead.