Risk warning. CFDs and leveraged FX carry a high risk of rapid loss and a majority of retail investor accounts lose money. General information, not financial advice.
Here is a cost that does not appear in a single broker comparison table, is invisible in the platform, and on a small account funded from outside the dollar and euro world can exceed everything else you pay combined.
It is the cost of moving between currencies — into the account, inside the account, and out of it again. And because it is charged as a percentage of a transfer rather than in pips on a trade, it never shows up next to the spread where you would think to look for it.
Where the three conversions actually happen
On the way in. You fund a US-dollar account from a bank account held in another currency. Somebody converts. It may be your bank, your card issuer, a payment processor or the broker — and whoever does it applies their own rate and their own markup. If more than one of them touches it, you pay more than once.
Inside the account. Your profit and loss on an instrument is calculated in that instrument's settlement currency. If that differs from your account base currency, it has to be converted every time a position is closed. Trade a yen cross on a euro-denominated account and this happens on every single ticket, quietly, in the background.
On the way out. Withdraw to a bank account in a currency that is not the account base currency and the whole thing runs again in reverse.
Three conversions, each with a rate and a markup, on money that was only ever supposed to sit in a trading account.
What the fee looks like when a broker publishes it
Some brokers publish this plainly, and the shape is worth learning from. IG's help centre, for UK spread bet and CFD accounts, states: "Our standard FX conversion fee is 0.7% which is added to the best available exchange rate provided from several banks."
That sentence is a useful template for reading any broker's disclosure, because it separates the two components you have to compare.
The rate the broker sources — here described as the best available from several banks.
The markup applied on top of it — here a stated percentage.
A broker that discloses both is easy to evaluate. A broker that says only "conversion at prevailing market rates" is telling you nothing, because a markup buried inside an unstated rate is invisible by construction. Ask for the percentage in writing. If it does not exist as a number, that is the answer.
We are not printing other brokers' conversion percentages here. They change, they differ by entity, and a wrong one on this page is exactly the figure a reader would act on. Find your own broker's on its costs and charges page, and note the date you read it.
Why the base currency choice is the decision, not the fee
The fee is the visible part. The base currency is the lever.
Every conversion you eliminate is a fee you never pay, so the question is not "which broker has the lowest markup" but "which base currency removes the most conversions from my particular life". There are three inputs and they can conflict.
The currency your money already lives in. Matching the account to your bank account kills the deposit and withdrawal conversions outright. Usually the single biggest saving, because those are the largest sums that move.
The settlement currency of what you trade. If you trade almost exclusively pairs quoted against the US dollar, a dollar-denominated account removes the per-trade conversion. If you fund in one currency and trade another, you are choosing which of the two conversions to keep.
Whether the broker offers your currency at all. Many offer a short list, and the currency you would ideally use may not be on it.
There is no universally right answer, which is precisely why the sign-up form's default is a bad way to decide. And because the base currency is frequently fixed for the life of the account, the two minutes you spend on that dropdown are worth more than a great deal of spread shopping.
A worked comparison you can run yourself
The arithmetic is simple and it is the only way to compare honestly, because a good rate with a large markup and a poor rate with a small markup can land in the same place.
Take the amount you intend to move. Ask each route — your bank, your card, a dedicated transfer service, the broker itself — one question: how many units of the destination currency will actually arrive?
That single output number includes the rate, the markup and any flat fee, so it is directly comparable. It also exposes the common trap where a route advertises "zero fees" and recovers the cost entirely inside a worse rate.
Run it on the amount you will really send. A flat fee dominates on a small transfer and is irrelevant on a large one, while a percentage markup behaves the opposite way, so the cheapest route genuinely changes with size. If you move money internationally often, a dedicated service such as Wise is worth pricing against your bank on this same "what arrives" basis — the comparison is the point, not the brand.
The counter-argument
Two honest objections.
The first is that for a trader funding a properly capitalised account once a year in their own currency, none of this matters. Correct. The conversion cost is a small-account and cross-border problem, and if you are neither, skip it.
The second is subtler and more important. It is possible to optimise this so hard that you pick a broker on its conversion fee and ignore whether it is well regulated, whether its execution is any good, or whether its entity in your country gives you meaningful protection. That is a bad trade. Conversion cost is worth a few minutes at account opening; regulation is worth considerably more, which is why how to choose a forex broker puts the licence check first and cost second.
The bottom line
Conversion cost is charged in percentages on transfers, not in pips on trades, so it hides from every comparison table on the internet. Choose the base currency that removes the most conversions from your own circumstances, get the broker's markup percentage in writing before you fund, and compare routes on what arrives rather than on what is advertised. On a small international account it is a larger lever than the spread — and it sits alongside the minimum withdrawal check as the two payment questions worth answering before the first deposit rather than after it.
Risk Warning
CFDs are complex instruments and come with a high risk of losing money rapidly due to leverage. Between 51-89% of retail investor accounts lose money when trading CFDs. You should consider whether you understand how CFDs work and whether you can afford to take the high risk of losing your money.
This article is general information, not financial advice. Conversion fees, available base currencies and rate sources are set by each broker and payment provider and change — verify the current figures on the provider's own costs and charges page.
Sources
- IG — currency conversion fees for spread bet and CFD accounts, UK help centre, read 2026-09-06: ig.com
Frequently Asked Questions
What is an account base currency?
It is the currency your trading account is denominated in — the currency your balance, your margin, your profit and loss and your statements are expressed in. It is normally chosen when the account is opened and is often difficult or impossible to change afterwards, so it is worth deciding deliberately rather than accepting the default the sign-up form offers.
When does a currency conversion charge apply?
At three separate points: when you fund an account in a currency other than its base currency, when you realise a profit or loss on an instrument whose settlement currency differs from your base currency, and when you withdraw to a bank account held in a different currency. A single trade can therefore carry a conversion cost even if you never consciously exchanged anything.
Is a broker's conversion fee the same as the exchange rate?
No, and separating the two is the whole skill. The fee is normally expressed as a percentage applied to an exchange rate the broker sources. IG, for example, states that its standard FX conversion fee is 0.7% added to the best available rate from several banks. Compare the all-in outcome — rate plus fee — rather than either number alone, because a good headline rate with a large markup can be worse than the reverse.
