The short answer
“No fees” almost always means “no advertised fee”. The cost has moved into the exchange rate. The provider obtains currency at one rate, gives you a worse one, and keeps the difference. Because you never see the rate they got, the charge is invisible unless you go looking for it.
There is only one number you need: the mid-market rate at the moment you send. Everything after that is arithmetic you can do yourself.
What the mid-market rate is
The mid-market rate is the midpoint between the buy and sell prices for a currency pair on the wholesale market. It is a reference point, not a retail offer — no consumer transacts at mid-market, and a provider quoting exactly mid-market with no fee would be working for nothing.
So the existence of a margin is not the scandal. The question is how large it is and whether anyone tells you. A provider that charges a visible €4 and shows you its margin is being more honest than one charging €0 and quietly taking 2%.
The spread is the fee
The arithmetic below uses round illustrative numbers to show the mechanism. They are not a quote from any provider and not a live rate — check both yourself, on the day, for the amount you actually intend to send.
Suppose you are sending €2,000 and the mid-market rate is 1 EUR = 1.0800 USD. At mid-market your money is worth $2,160.
Provider A advertises “zero fees” and quotes you 1.0530.
€2,000 × 1.0530 = $2,106.00 delivered
mid-market value = $2,160.00
cost of the transfer = $54.00 (2.5% of the amount sent)
advertised fee = €0.00Provider B charges a visible €4 fee and quotes you 1.0790.
€2,000 − €4 fee = €1,996 converted
€1,996 × 1.0790 = $2,153.68 delivered
mid-market value = $2,160.00
cost of the transfer = $6.32 (0.29% of the amount sent)
advertised fee = €4.00Provider B charges a fee and is roughly eight times cheaper. The headline number told you the opposite. This is the entire reason “no fees” survives as a marketing claim: it is technically true and practically misleading, and the only defence is to compare delivered amounts rather than fee lines.
The four other places cost hides
The spread is the big one, but it is not the only one, and the remaining four are easier to miss because they land after you have committed.
1. Intermediary bank deductions. A traditional bank wire may pass through one
or more correspondent banks, each of which can take a cut. In the SWIFT message
that carries your payment, field 71A records who pays these charges: OUR means
the sender covers them, BEN means they come out of the beneficiary’s money, and
SHA splits them. If your transfer is SHA or BEN, the amount your recipient
sees can be lower than the amount you were quoted, and neither you nor your
provider controls by how much. Ask which applies before sending anything large.
2. Charges at the receiving end. The recipient’s own bank may levy an inbound transfer fee, and a cash-collection point applies its own margin when converting to notes. This is invisible from your side entirely — the only way to learn it is to ask the person receiving the money what actually arrived.
3. How you fund it. Paying by credit card can be treated as a cash advance by your card issuer, which typically means interest from day one and no grace period. If your card is denominated in a different currency from the transfer, your issuer performs its own conversion at its own margin, on top of the provider’s. Funding from a bank balance in the same currency avoids both. If you fund by connecting a bank account, it is worth understanding what you are actually agreeing to when you grant that access.
4. Timing. Wholesale currency markets close. Some providers widen their margin outside market hours and at weekends, precisely when consumers are most likely to be sending money. A “guaranteed rate” is normally guaranteed for a stated window — often minutes — after which you are re-quoted. Read the window.
How to check any provider in about a minute
- Get a mid-market reference for your pair, and note the timestamp. Any independent rate source will do; what matters is that it is not the provider quoting you.
- Get the provider’s delivered amount — not the rate, the number of units the recipient actually receives, after all fees, for the exact amount you intend to send.
- Divide. Delivered amount ÷ mid-market value. Subtract from 1. That is your real cost as a percentage, fees and spread combined.
- Write down the date and time. A margin you measured last month tells you nothing reliable about today, because these are revised continuously and without announcement.
The transfer cost calculator on this site does step 3 and shows its working, so you can check the arithmetic rather than trust it.
Two things that make comparisons wrong
Comparing at the wrong amount. Margins are frequently tiered. A provider that is cheapest at €200 may not be cheapest at €5,000, and a fixed fee that looks trivial on a large transfer dominates a small one. Compare at the amount you actually send.
Comparing at the wrong moment. A single snapshot catches one moment of one provider’s pricing. If you send regularly, sample the same corridor a few times across different days before concluding anything.
What this does not tell you
Cost is not safety. A provider can be the cheapest option and still be poorly regulated, hold your money in an account with no deposit protection, or have a thin security record. Those are separate questions with separate answers, and a good rate is not evidence about any of them.
Cheapest is also not always the goal. Speed, the recipient’s collection options, and whether the provider is licensed in both jurisdictions can all matter more than 30 basis points. The point of the arithmetic is not to force you to the lowest number. It is to stop you paying 2.5% while believing you paid nothing.