Why do banks charge so much for currency conversion

If you coordinate cross-border deals — whether you’re a broker splitting proceeds between parties in two countries, an advisor whose fee gets wired across an ocean, or a closing professional disbursing funds to recipients who hold accounts in different currencies — bank currency conversion cost is a number that routinely eats into what people actually receive. It is also a number almost no one fully understands, because banks are not particularly motivated to explain it. The quoted exchange rate looks like the whole picture. It isn’t. Behind that rate sits a layered cost structure, each layer with its own logic and its own claim on the money. Understanding why that cost is as high as it is — not just that it is — puts you in a meaningfully better position to anticipate it, explain it to clients, and structure disbursements so that conversion drag doesn’t become a surprise at the worst possible moment.

The rate you see is not the rate banks use for each other

Every explanation of bank conversion cost has to start here, because this is where the confusion begins. When you search any currency pair online, the rate displayed is the mid-market rate — also called the interbank rate or the spot rate. It represents the midpoint between the bid and ask prices at which large banks trade currencies with each other in the wholesale market. It is the closest thing to a “true” exchange rate.

No business, however, transacts at the mid-market rate. That rate is what banks charge each other when they trade at wholesale scale. When you or your client needs to convert currency, you are a retail customer — and retail customers get a different rate entirely. Banks profit from FX by offering customers a rate that includes a markup above the interbank rate at which they source currency. The difference between the two rates is retained by the bank.

This markup is the mechanism, and it is deliberately quiet about itself. It is the real exchange rate plus a margin — a margin that is deliberately embedded in the rate rather than listed as a charge, and one that most businesses have never explicitly agreed to or even calculated. There is no line item for it on a bank statement. You see the amount that arrived, and you’re left to compare it against whatever rate was in effect at the time of transfer if you want to figure out what was taken. Most people never do.

Typical bank FX margins on business international transfers range from 2% to 4%, though some institutions charge more for less common currency pairs or smaller transfer volumes. To translate that into real numbers at deal scale: on a $500,000 disbursement, a 3% embedded markup is $15,000 that quietly disappears from the recipient’s proceeds. It lands nowhere on any closing statement. It isn’t a disclosed fee. It is simply the gap between the rate the bank sourced currency at and the rate it gave your client.

Why the markup exists — the legitimate reasons

Banks don’t charge conversion markups out of pure opportunism, though revenue is certainly a driver. There are genuine structural reasons why intermediating currency exchange costs something, and understanding those reasons helps you think clearly about when the cost is justified and when it isn’t.

Liquidity and inventory risk

When a bank converts currency for a customer, it takes a position — even if only briefly. It needs to hold or acquire the foreign currency, which means it’s exposed to rate movements between the moment it commits to a conversion rate and the moment it completes the transaction. Banks often incur losses on these transactions due to various reasons, including fluctuating exchange rates and other related risks. The foreign currency markup fee is an outlet for banks to cover these costs and also generate a profit.

This risk is real, though it is priced somewhat conservatively. FX costs frequently spike when primary markets are closed. During weekends or bank holidays, financial institutions widen their spreads or use “rate freezes” to create a risk buffer against potential market gaps that might occur when trading resumes on Monday. If you have ever noticed that an international wire initiated on a Friday seems to convert at a worse rate than one sent mid-week, this is why. The bank is pricing in the uncertainty of not being able to hedge for several days.

Infrastructure and operational overhead

Banks’ platforms weren’t built exclusively around currency conversion. They maintain extensive branch infrastructure, compliance overhead, and operational costs that specialists don’t carry. Those costs are recouped, in part, through FX margins.

Foreign currency conversion requires a dedicated staff and associated infrastructure. Hence, banks charge a forex markup to cover the operational and infrastructure costs related to foreign currency conversion. This includes treasury desks, compliance teams, systems that monitor transactions for sanctions and fraud, and reporting obligations to regulators across multiple jurisdictions. None of that is free, and FX conversion revenue is one of the products that subsidizes it.

Revenue generation — the honest answer

The cleanest answer to why bank conversion costs so much is that it is a significant profit center and banks have little competitive pressure to lower it. While banks claim it covers the cost of currency conversion, it’s primarily a significant revenue stream for them. The markup is embedded in the rate rather than disclosed as a fee, which means most customers never price-compare it the way they would a wire transfer fee or a service charge. None of this is a conspiracy. It’s simply a business model — one that works very well for banks, and that quietly costs their business customers a great deal over time.

The cost structure in full: more than just the rate markup

The exchange rate markup is the largest single component of conversion cost, but it rarely operates alone. The exchange rate markup is the highest cost, but it’s rarely the only expense affecting your savings. International transfers through traditional banks often incur several layers of fees that together represent the true cost of moving money across borders. A complete picture includes the following.

The sending bank’s flat fee

First, your bank charges a flat outgoing fee, typically $30 to $50. This is the most visible piece — it shows up as a line item, it’s disclosed at the time of the transfer, and it’s the number most people focus on. In a large-value transaction, this flat fee is almost noise compared to the embedded spread. At a 3% markup on a $400,000 disbursement, the invisible cost dwarfs a $45 wire fee by a factor of more than 260.

Correspondent bank deductions

This is where things get complicated and, for professionals managing disbursements, potentially frustrating. SWIFT (Society for Worldwide Interbank Financial Telecommunication) does not even conduct money transfer per se, but operates as a safe international messaging system, which banks utilize to issue payment codes to one another. The physical money is transferred across the banks using the system of correspondent banking relationships. Because a SWIFT wire transfer often involves multiple banks — your bank, the recipient’s bank, and potentially one or more intermediary banks — each institution involved in the chain may levy its own fee for processing the transaction.

The practical result is that the amount reaching the recipient can be less than what was sent, and by an amount that nobody disclosed upfront. When you send money to a bank account outside of its originating currency, it usually goes through the SWIFT network. This is a network of banks that help process the payment until it gets to your destination country. Sending money via SWIFT is a bit like travelling from one airport to another — it’s not always possible to take a direct flight to the city you’re travelling to, so you may need to take connecting flights. SWIFT works the same way.

SWIFT transfers typically pass through one to three correspondent banks, each of which charges a handling fee. With SWIFT intermediary bank fees ranging from $15 to $35 per hop, a two-hop transfer can add $30 to $70 in deductions before the money arrives.

It is very hard to know how many intermediary banks are going to be in the transaction and how much each will charge, since it depends on the various currencies involved and the countries and banking relations. This unpredictability is professionally significant: if you are disbursing an exact agreed amount to a recipient abroad, correspondent bank deductions can create a shortfall that requires explanation and potentially a follow-up transfer.

The receiving bank’s incoming fee

Even after your money arrives at the destination bank, the recipient’s institution may charge a fee to process and credit the incoming wire. This is called the receiving fee or incoming wire fee. Receiving fees vary widely by country and institution. The receiving bank may charge an incoming wire fee of $10 to $25. Again — not disclosed to the sender, often a surprise to the recipient.

The total stacked cost

Traditional bank wire total costs typically range from 4% to 8% of the transfer amount, combining sending fees, exchange rate markups, and potential intermediary charges. At that range, on a $250,000 advisor fee being wired internationally, the total drag is anywhere from $10,000 to $20,000. That is the real number. It is the gap between what the deal terms said should land and what actually arrives.

Why smaller sums and exotic pairs cost proportionally more

The bank’s cost structure doesn’t scale linearly with the transfer amount. Flat fees — the outgoing wire charge, the receiving fee, each correspondent’s cut — are the same whether you’re moving $20,000 or $2,000,000. So as the transaction size decreases, those fixed components become a larger percentage of the total.

Cross-border fees disproportionately impact SMEs because they typically have lower transaction volumes and less negotiating power with banks. Unlike large corporations that can negotiate better rates, SMEs often pay standard retail markups that can significantly affect their profit margins.

Currency pair also matters materially. Sending dollars to euros or dollars to sterling involves liquid, heavily traded pairs where the bank’s own cost of acquisition is low and spreads are tighter. Move into less liquid corridors — dollars to Polish zloty, euros to South African rand, sterling to Turkish lira — and the bank’s own hedging cost increases, competition thins, and the markup widens. The cost of a transfer is not uniform across all destinations. Sending USD to GBP or EUR is typically cheaper than sending to currencies in Africa, South Asia, or the Pacific. Providers have better liquidity and more direct routing relationships for major currency pairs.

For professionals working on cross-border deals involving parties in emerging markets, this is not a minor consideration. A disbursement to a recipient bank in Lagos or Karachi or Jakarta may pass through more correspondent hops, each extracting its fee, while also facing a wider markup on the conversion itself. The total leakage can substantially exceed what either party anticipated when the deal was structured.

The timing problem: when the rate you quoted isn’t the rate that lands

There is a second dimension to conversion cost that sits alongside the markup: rate timing. Exchange rates fluctuate continuously. When you initiate an international wire, there is often a gap — sometimes hours, sometimes a full business day — between when you instruct the transfer and when the bank actually executes the conversion. Some banks hold your funds for days before converting them, potentially exposing you to unfavorable rate movements.

In a deal context, this creates a specific problem. You agree to disburse a certain amount in local currency. The rate at the moment of agreement is one thing. The rate at the moment the bank converts is another. If markets moved against you in the interval, the recipient gets less than expected — and the bank has no obligation to absorb that difference or even explain it clearly.

There are multiple factors that comprise the cost of an FX payment. These factors include base exchange rate (including internal profit), spread, cost of funds, correspondent banking transaction fees, and fees charged by the bank originating the transaction. Every one of these factors can move independently between instruction and settlement. The person disbursing the funds carries the risk of that movement.

How the markup is kept quiet — and why you might never have noticed

Most of the cost lives inside the quoted rate, not alongside it. Most consumers remain unaware of FX markups because the conversion process is handled automatically by the payment rail during settlement. Because the final amount is simply debited from a bank account in the local currency, the underlying spread remains buried within the transaction total.

There is a stark difference between seeing a final price and understanding the rate formation. While a statement provides price visibility, true transparency regarding the markup over the mid-market rate is usually absent, leaving the cardholder unable to benchmark the fairness of the deal.

The practical result is that the only way to quantify what a bank took in conversion is to find the mid-market rate that was in effect at the moment the conversion occurred, compare it to the rate the bank applied, and calculate the percentage difference. Most clients — and, frankly, most professionals — never do this. Your statement may just show “Amount credited: [X]” without any breakdown. It’s on you to realise a markup was taken.

Some institutions will disclose the rate if you ask directly. Others won’t make it easy. Banks and currency exchange providers are seldom fully forthcoming about how these fees are levied from your transfer, with different institutions adhering to very different degrees of transparency in this regard. Some currency exchange providers will completely omit any mention of this fee on their consumer-facing money transfer websites, instead burying the details deep within their terms and conditions.

What actually drives the variation between institutions

Not all banks mark up conversion the same way, and the variation is substantial. Several factors determine where any given institution lands.

The size of the institution and its FX infrastructure. Large banks with global treasury operations trade in much higher volumes and have tighter costs of acquisition. Large international banks with extensive global networks might charge higher fees but require fewer intermediaries. Smaller banks might charge lower upfront fees but must route your payment through more intermediaries, potentially resulting in higher total costs. Whether you save money dealing with a large or small institution depends on the specific corridor and currency pair.

The nature of the client relationship. Banks with significant volumes of FX business do negotiate with large corporate clients. Larger businesses can often negotiate better rates. If you are regularly disbursing across borders as part of your professional practice, there is a conversation to be had with your bank about rate treatment — particularly if the aggregate annual volume is meaningful.

The currency pair and the correspondent network required. As discussed, liquid major pairs are cheaper to convert. The bank’s internal costs determine a floor on what it will offer — a floor that rises sharply for exotic currencies and indirect routing.

The time of transaction. FX costs frequently spike when primary markets are closed. During weekends or bank holidays, financial institutions widen their spreads or use “rate freezes” to create a risk buffer. Initiating large-value international transfers during active market hours on a business day generally produces better rates than weekend or holiday wires.

The currency pair problem in deal disbursements specifically

For a broker, advisor, or deal professional managing disbursements across multiple parties, the conversion question has an added layer: who bears it, and on which side of the wire. If the deal is denominated in dollars and the recipient holds a euro account, conversion happens somewhere. The question is where — at the sending bank before the wire leaves, at a correspondent bank mid-chain, or at the receiving bank when the dollars arrive.

When sending an international payment through the SWIFT network, it’s important to understand the different charge bearer codes that can be used to split the fees associated with a transfer between the originator and beneficiary. In order for the beneficiary to receive payment in full, the sender must cover any transfer-related fees which are to be paid on top of the explicit amount sent to the beneficiary.

These SWIFT charge bearer codes — technically referred to as OUR (sender pays all fees), BEN (beneficiary pays all fees), and SHA (shared) — give the initiating party some control over who absorbs the correspondent bank fees. They do not, however, control the FX markup. That is locked in at the point of conversion regardless.

Some financial institutions charge commissions for handling and executing the FX conversion, either as a fixed fee (irrespective of value), or a relative fee (the higher the value, the higher the commission). Additionally, banks commonly charge for reporting, posting payments to accounts, and running analytics on accounts. In deals where the professional is responsible for accurate disbursement to each party, layered costs like these — especially when partly invisible — can create post-close disputes if a recipient expected one number and received another.

What you can actually do about it

Understanding the why is the precondition for doing something about it. The conversion cost problem does not resolve itself. It requires deliberate choices upstream.

The most effective single step is comparison. Many banks widen the gap between the mid-market rate and the rate they offer to customers. Industry research often places this margin at 2–5% of the transfer amount, meaning the exchange rate can be the highest cost in the transaction. Specialist FX providers — institutions whose core business is currency conversion rather than retail banking — typically operate at tighter margins because their entire value proposition rests on the conversion itself. Specialist FX brokers and platforms typically offer tighter margins than high-street banks — often 0.2% to 0.8% for SMEs — because their business model is built around FX rather than cross-subsidising it with other banking products.

That spread in margin — from 0.5% at a specialist to 4% at a high-street bank on the same corridor — is real money at deal scale. On a $300,000 disbursement, it is the difference between $1,500 in conversion cost and $12,000.

Consolidation helps too. Every time a separate conversion is initiated, fixed costs stack: flat fees at origin, potential correspondent deductions, receiving fees. Instead of making multiple small transfers, consolidate payments when possible. Larger transactions often qualify for better rates and lower percentage markups. Professionals managing multi-party disbursements can often reduce total conversion cost substantially by structuring the flow so that conversion happens once, not multiple times.

Holding multi-currency balances — when the professional or the deal structure permits it — eliminates repeated conversion entirely on recurring corridors. Holding balances in multiple currencies can help you avoid repeated conversions and associated markups. This is particularly valuable for businesses with predictable international payment patterns.

Where precision matters most

For professionals who coordinate the financial close of a transaction, conversion cost is not just a background administrative inconvenience. When you’re managing the disbursement of proceeds across multiple recipients in multiple currencies, the difference between what was agreed and what lands depends entirely on how cleanly the conversion executes.

Shaka handles the split routing — the professional sets the recipient wallets and the percentage each party receives, and the funds move directly in a single transaction. Where the funds need to land in specific currencies, knowing the true conversion cost ahead of time — not as a surprise revealed by the statement — is what separates a clean close from a post-close conversation you don’t want to have.

The bank’s model is built around converting currency in a way that obscures its own cost. The professional’s job is to know that cost going in, structure disbursements to minimize it where possible, and ensure that every recipient receives what the deal terms actually promised.

Why this isn’t changing fast

Frequently, the complex cost-base described above is justified by incumbents due to complex and legacy technology. Banks’ conversion infrastructure is deeply embedded in decades-old systems, correspondent relationships built over generations, and regulatory frameworks that differ by jurisdiction. Unwinding that is not a short-term project.

Financial institutions have traditionally faced significant challenges in making cross-border payments, especially in navigating the complex web of regulatory frameworks in different countries. These ordinances can vary widely and often require substantial resources to ensure compliance, let alone timely delivery. To complicate matters, legacy systems are often outdated and not equipped to handle the speed and efficiency required for today’s near-instant cross-border transactions.

None of which means the cost is immovable for you. Specialists have built better infrastructure. For a UK SME converting GBP to USD, a typical high-street bank margin might range from 1.0% to 3.0% above the mid-market rate. On a £100,000 conversion, a 2% margin costs you £2,000 in hidden charges — money that never appears as a line item on your bank statement but is embedded in the rate you receive. Over a year, a business converting £1 million in foreign currency could be paying £20,000 or more in margins without ever seeing a separate “FX fee” on any statement.

The bank’s conversion cost is high because conversion is expensive to run at retail scale, because the risk of rate movement has to be hedged somewhere, and because the markup is hidden in a way that removes competitive pressure. Those structural facts explain the cost. They do not obligate you to absorb it without questioning it. Every professional who moves money across borders on behalf of clients has both the standing and the reason to know exactly what the conversion is costing — before the wire goes out, not after the statement arrives.