Overbit is mainly compensated for its services through the “market spread”. For example, when trading BTC/USD, if the Buy Price is 8,000, then the Sell Price would be 7,995 respectively (which means a market spread of 5 pips, in this example). The spread is not fixed and changes from time to time during volatile periods to account for minimum slippage when the trade is executed. The spread is also used to guarantee liquidity for the trade and it means users can easily calculate their profit or loss for each position without taking commissions into account.
Unlike other service providers who also charge commissions on each trade, Overbit does not charge dealing commissions.
Are there any hidden fees?
No, there are no hidden fees. All fees are explained in the contract specification page.