For that you will have to look into the profile of an individual broker. Some brokers are able to offer zero commission trades and spreads because of their tie up with liquidity providers. Fxview and XTB are examples of such brokers. However, some brokers like Pepper-stone compensate for the low trading fees with higher spreads. Their spreads start only from 1.0 pips, which is a big amount in Forex trading.