Bitcoin Forum

There won't be any minor charge in trading eventhough we are transacting BTC from one address to another.

so, is that an illusion which Exchanges (BITTREX,CEX.IO,...etc) doing only exchange numbers from 1 account to another??

The only steps where BTC change addresses in an exchange's hot wallet is when
1) someone deposits some coins onto the exchange or
2) someone withdraws some coins from the exchange.

While trading there are no BTC moving around. You deposited BTC's and from this moment on they are in charge of them.
If you trade your BTC for ETH or whatever the only thing happens is that your account on this exchanges get -BTC credits and +ETH credits.
This doesn't mean that their coins have moved in the background while this trade happened.
You can compare it to tokens with 1:1 value to coins. Trading tokens (on the exchange site) is free, but withdrawing/depositing BTC's costs TX fee.
And for depositing 1 BTC you get 1 btc token (Just to simplify the whole principle).

There are charges for trading in exchanges but those are just the trading fees and not actual transaction(miner)fee. The BTC stays still while the numbers are calculated for the particular account. The exchanges charge upto 0.25% per trade and that is how they make money. The BTC is stored in their wallet and whenever you make a deposit or withdrawal the BTC is directly adjusted from their wallet. This is why some exchanges like yobit has the ability to transfer BTC from 1 account to another without any fees within the exchange.