The forex markets are great because they are open almost all of the time and there are a wide range of currencies to choose from. This brings up an important question.

What are the most active hours for forex trading?

Generally speaking, the most active hours all around are between the London markets opening around 8:00 GMT and end with the markets in the US closing around 22:00 GMT. The absolute busiest time in the forex markets are during the London to US overlap between 13:00 GMT to 16:00 GMT. These are the hours that are the most liquid or when the most traders are in the markets making trades. If your intention is to do daytrading, these are key hours!

What are the major sessions for forex trading?

There are 3 major sessions each day in the forex markets. They are the London session, the US session, and the Asian Session.

The London Session
The London session starts around 8:00 GMT and winds down around 1600 GMT. The currencies that are the most active during these hours are EUR, GBP, and USD.

The US Session
The US session starts around 1300 GMT and winds down around 22:00 GMT. The currencies that are the most active during these hours are AUD, EUR, GBP, JPY, and USD.

The Asian Session
The Asian session is a reasonable quiet session on most days. All pairs are pretty slow moving and it is not a good time to day trade. The only real currency that has noteworthy activity is the JPY and the activity is slow unless a major financial event happens.

Summary

The best hours for trading the forex markets, no matter your method, are during the London and US session overlap. The markets are full of active participants during these hours and the currencies really move. For the most part, even the larger fundamental news comes out during these times. Trading during these hours is your best chance to get in while the market is making decisive moves and it will be your best chance to score quick profits.