A broker earns money every time you trade, whether you end up in profit or not. The spread alone covers a lot of that, but it is rarely the whole story.

Knowing where the money comes from helps you read an account’s terms instead of just its headline price.

The Spread

The spread is the gap between the buy price and the sell price on any instrument. You pay it the moment you open a trade, since the price needs to move in your favour just to cover that gap.

A broker can mark up the raw price it gets from its own liquidity sources and quote you something slightly wider. That markup is pure income, earned on every trade regardless of the outcome.

Commission

Some accounts charge a flat commission per lot instead of, or on top of, a wider spread. This is common on accounts built around raw or near raw pricing, where the fee sits separate from the price itself.

Commission scales with volume. A broker earns more from an active trader placing many lots a month than from someone who trades rarely.

Some accounts charge commission on both sides of a trade, once to open and once to close, billed together as a round turn fee. Others charge only when you close the position. Either way, the fee is fixed per lot, so it does not change with how far the market moves.

Swap and Overnight Financing

Hold a position past the daily rollover and you pay or receive a swap charge. It comes from the interest rate gap between the two currencies in a pair, or a benchmark rate on other instruments.

The broker usually keeps a cut of that rate rather than passing on the exact market figure. Over many open positions and many nights, this becomes a steady source of income.

Traders who close every position before the daily cut off never pay this fee, which is why short term trading and swap costs rarely come up together.

Taking the Other Side of Your Trade

Some brokers send every client order out to the market and earn only from the spread or commission. Others keep some orders on their own book, meaning the broker profits when the client loses and pays out when the client wins.

Most brokers today run a mix of the two, routing some flow to the market and holding the rest, based on the size or type of the order. Reading how a broker handles this split matters when you compare a best forex broker against another, since it shapes the incentive behind your pricing.

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Paying Introducing Brokers and Partners

Part of what you pay in spread or commission can fund a payment to whoever referred you to the broker. An introducing broker earns an ongoing share tied to how much you trade, paid out of the broker’s own revenue rather than as an extra charge on your account.

This does not change what you pay directly, since the split happens on the broker’s side. It does explain why brokers spend heavily on referral programs, since a referred client who trades often keeps paying out for years.

Fees Beyond the Trade Itself

Interest on client deposits sitting in a broker’s accounts can add a small, steady stream of income that has nothing to do with your trading activity. Account fees, where they exist, work the same way, sitting apart from the spread and commission you pay on each order.

Fees From Other Services

Brokers that offer social features earn from those too. A common example is What is copy trading, where a strategy provider takes a performance fee, a cut of the profit earned by the people copying their trades.

The broker platform hosting that service usually takes a share of the same fee. So the broker earns on the trade itself and again on the performance fee attached to it.

Why This Matters to You

None of these fees are hidden exactly, but they rarely sit next to each other on one page. Spread, commission, swap and any extra charges all add up across a month of trading.

Add them together for your own trading pattern before you judge whether an account is cheap. A tight spread with a high commission can cost more than a wider spread with none, depending on how often you trade.

Ask a broker directly how each of these revenue sources applies to your account type. A straight answer on spread, commission, swap and any partner payouts tells you more than a page of marketing copy ever will.