Your broker is one of your most important partners in your trading success. They should be fair and reliable. To that end, these are the brokers that I recommend.
Obviously, you should do your own due diligence when selecting a broker. These brokers may not be a good fit for all traders, so figure out what works for you. By trading with these brokers, you accept 100% responsibility for your choice.
This is not trading advice, just my opinion.
Oanda

I've traded with Oanda US for years and they provide a feature that is vital to the success of new and experienced traders alike…nano lots.
This allows traders to take exactly the right amount on risk on every trade and is especially important for traders who are starting out with small accounts.
Other brokers that only allow trading through MetaTrader require you to round your lot size to the nearest micro lot.
When traders are forced to round their trades up they are taking more risk than is optimal and can lead to bigger drawdowns.
When traders have to round down, then aren't making as much as they could be. If their wins don't make up for their losses, they can experience losses, even when their trading strategy should have positive expectancy.
So if you are in the US, my favorite US broker is Oanda.
You can trade with Oanda in other countries, so that might be an option for you too.
Learn more about Oanda here.
Update: Oanda now offers crypto trading.
Scandinavian Capital Markets

Regulations in the US and many places in Europe have become more and more restrictive.
The primary downside of this is that available leverage in Forex trading has gone down considerably. Sure, too much leverage can be dangerous for beginners.
But not enough leverage is dangerous for professionals.
Full-time traders with large accounts spread their money across multiple brokers and prefer to keep a large chunk of their trading funds in their bank. This protects them from surprise market movements. However, this also means that they need more leverage to comfortably execute trades.
This is where a broker like Scandinavian Capital Markets is a huge asset. They are regulated in Sweden and provide good (but not excessive) leverage.
The best of both worlds.
If you are a full-time trader, then I recommend talking to Scandinavian Capital Markets.
I have met with them personally and feel that they are one of the few regulated, non-US brokers that are operating with integrity and actively work on establishing positive business relationships with their clients.
Scandinavian Capital Markets is not for new traders. You should have some experience in trading before signing up with them.
But if you are outside the US and you are an experienced trader, I feel that they are an excellent option. Since I'm in the US, I can't trade with them. But I would, if I could.
Learn more about Scandinavian Capital Markets here.
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