Spread vs commission vs swap: what a trade really costs

These are not three fees. They are one bill, presented at three different moments: the spread the instant you click, the commission as a line on the way in and the way out, and the swap every night the position is still open. One standard lot of EUR/USD, held from one afternoon to the next, costs somewhere around $13 before the price has done anything at all.

Most cost comparisons stop at the spread, which is the only one of the three that never appears as a charge. Here is where each one is taken from you, and what the three add up to on a single ordinary trade.

The same bill, three moments

Read the third column. Only one of the three arrives labelled as a cost, and it is the one that many brokers advertise loudest as the thing they do not charge you.

The spread is charged once, at the click

The spread is the gap between the price you buy at and the price your position is then valued at. You do not pay it; you simply start behind by it. Our explainer puts the mechanic plainly: you buy at the ask and the trade is marked at the bid, so the market has to move in your favour by the width of the spread before you are level.

It is charged on the round trip — entry and, implicitly, exit — and it is the same money whether you close in ten seconds or in ten weeks. On EUR/USD a typical 0.8-pip spread on one standard lot is about $8, because one pip on 100,000 units is worth roughly $10.

That fixed-once quality is what makes it the dominant cost for a scalper and a rounding error for a position trader. The same $8 is enormous against a ten-pip target and irrelevant against a four-hundred-pip one.

The commission is the honest one

On a raw or ECN (electronic communication network) account the broker shows you something close to the interbank spread and charges separately for the execution. It is the only one of the three you can read off a statement without doing arithmetic first.

It is also the one that makes broker comparison misleading, because a raw account is not cheaper — the cost moved. Our spread explainer does the comparison in pips: a raw spread of 0.2 pips plus a commission worth roughly 0.7 pips is 0.9 pips all-in, against 0.8 pips on a standard account that bundles everything into the quote. On one standard lot of EUR/USD that is $9 against $8, and which of the two wins depends on the pair and the hour rather than on the headline.

In money, the commission on that raw account works out at about $7 for the round trip — roughly $3.50 each way per standard lot. Your broker's figure will differ; the shape of the comparison will not.

The swap is the only one that keeps charging

The swap, or rollover, is interest. Holding a currency pair means holding one currency and borrowing the other, and at the daily rollover — usually 5 PM New York time — the difference is settled on your account.

Its starting point is the gap between the two policy rates, and that gap is public. As of 23 September 2026, the Federal Reserve Economic Data (FRED) series for the upper bound of the Federal Reserve's target range stands at 4.00%, and the European Central Bank's deposit facility rate at 2.50%: a gap of 1.50 percentage points in favour of the dollar.

So a trader who is long EUR/USD holds the lower-yielding currency and borrows the higher-yielding one, and pays. On the $114,110 that one standard lot of EUR/USD represents at 1.1411 — the European Central Bank's reference rate that same day — 1.50% a year is $1,711.65, which divided across the year is roughly $4.70 a night.

Two things make the real bill worse than that:

• The $4.70 is a floor, not a bill. As our swap explainer says, the differential is the starting point and brokers add a markup to both sides — which is why a negative swap is usually worse than the raw differential implies and a positive one smaller. Two brokers can quote different swaps on the same pair on the same night.
• Wednesday counts three times. Spot forex settles two business days forward, so the Wednesday rollover carries the weekend with it. A week held is seven days of swap, not five.

One round trip, in money

One standard lot of EUR/USD, opened one afternoon and closed the next, on a $5,000 account, with our own reference figures rather than your broker's. Nothing here depends on the price moving.

Against the $114,110 the position controls, both numbers look like nothing. Against the $5,000 that is actually yours, one overnight trade has cost about a quarter of a percent of the account before the first tick.

And the ranking flips with time. On the standard account the spread is the biggest cost for exactly one night; by the second night the accumulated swap has passed it, and by the end of a week — seven days of swap, triple Wednesday included — the swap is around $32.90 against a spread that is still $8.

The swap row, though, is the one you can delete. The same round trip closed before the rollover pays the spread and the commission and nothing else — $8 on the standard account rather than $12.70, and $9 on the raw one rather than $13.70. That is what the three moments mean in practice: two of the costs are set by the size of the trade and the third by the clock.

What moves the bill?

• The hours you trade. The spread is not a constant. Our spread explainer lists them: thin conditions, the daily rollover itself — when liquidity providers change books — the first quotes after the weekend, which are the widest of the week, and the seconds around a scheduled release, a widening that starts before the number rather than after it.
• The direction. Long EUR/USD pays the differential; short EUR/USD earns it, at least before the markup. On a wide enough differential this is the whole basis of the carry trade — and the reason that trade is dangerous, because it accrues slowly and unwinds fast.
• The pair. Everything above is EUR/USD, the most heavily traded pair and normally the tightest spread. On an exotic both the spread and the swap are multiples of these figures.
• The size. All three scale with the lot, not with your account. On a mini lot every figure above divides by ten; the percentage of a proportionally smaller account is identical.
• Anything with a volume condition attached. A deposit bonus is repaid in spread at a rate you did not set: by our own arithmetic it takes 62.5 standard lots of EUR/USD to clear a $500 one.

What this does not cover

These three are not all of the costs, and the figures above are ours rather than yours.

• Slippage is a fourth cost and is not in the table. It is the difference between the price you asked for and the price you got, it is worst in exactly the conditions that widen the spread overnight, and it has no fixed size.
• Currency conversion, inactivity and withdrawal fees sit outside the trade entirely and vary more between brokers than anything above.
• Swap-free accounts. Some brokers advertise them. What replaces the nightly interest is set by the broker rather than by the rate gap, and we have not looked at those terms — treat it as a different bill, not as no bill.
• Every figure here is a reference point, not a quote. The spread, the commission and the markup on the swap are your broker's to set, and they are published in its contract specifications. The arithmetic is what transfers; the numbers are what you look up.

The takeaway

Ask how long you intend to hold, because that decides which of the three matters. Inside the day it is a spread question, and the account type and the hour are what you optimise. Past a couple of nights it is an interest question, and the pair's rate differential quietly becomes the largest number on the list.

The trap is comparing brokers on one line of the bill. "Zero commission" means the cost is in the spread, "from 0.0 pips" means it is in the commission, and neither claim says anything at all about the swap you will pay on night three.