What the mid-market rate is
At any moment, the market for a currency pair has two prices: the bid, at which dealers will buy the base currency, and the offer, at which they will sell it. The mid-market rate is the midpoint between those two prices. It is sometimes called the mid rate, the interbank rate or the real exchange rate, though those labels are used loosely.
The calculation is simple. Add the bid and the offer together and divide by two. If EUR/GBP is quoted at 0.8498 bid and 0.8502 offer, the mid-market rate is 0.8500.
The mid is a calculated figure. It describes the centre of the market at a point in time. It does not describe a price at which anyone has agreed to trade. That distinction sounds academic until you try to deal at it.
Why nobody deals at the mid
A trade needs two sides. When you buy a currency, someone has to sell it to you, and that someone wants to be paid for doing so. In the wholesale market, market makers stand ready to buy at the bid and sell at the offer. The gap between those prices is how they are compensated for holding risk, using their balance sheet and running their operations. If they bought and sold at the same price, they would earn nothing for taking on the risk that the market moves against them before they can offset the trade.
So even large banks dealing with each other pay something away from the mid. They cross the spread. A business client, reaching the market through an intermediary, pays the wholesale spread plus the intermediary's margin. That is normal and fair. What matters is how far from the mid you are dealing, and whether that distance is reasonable for the pair, the amount and the service.
Offers to convert "at the mid-market rate" usually recover their costs somewhere else, for example through a separate percentage fee, a subscription or a less favourable rate at weekends. That can be a perfectly honest model. It simply means the total cost has to be calculated, as with any other provider.
Where the numbers you see come from
There is no single official mid-market rate. Because FX trades across many venues and relationships at once, every data provider builds its own view of the market from the prices it can see. Financial data terminals, news services, search engines, currency apps and banks each publish figures that are close but rarely identical.
The differences come from several sources. Feeds may be drawn from different banks or venues. Some update every second, others every minute or less often. Some figures are delayed. Some websites show a single blended figure for the whole day. At quiet times, or in less traded pairs, these differences can be large enough to matter on a business-sized conversion.
For benchmarking, choose one source and stick to it. Consistency matters more than which source you pick. Note the time of the figure as well as the figure itself.
Reference rates and fixings
Reference rates are a different thing again. The European Central Bank publishes daily euro foreign exchange reference rates against a range of currencies. The Bank of Canada publishes daily exchange rates for the Canadian dollar. Market fixings, set at specific times each day from observed trading, are used by fund managers and index providers.
These figures are produced once a day for a stated purpose, often information, accounting or benchmark calculation. The European Central Bank states that its reference rates are for information purposes only. They are not live prices, and the market can be some distance from them by the time you trade.
Reference rates are useful for translating balances in financial statements or setting a consistent rate in an intercompany agreement. They are poor tools for judging the cost of a trade you booked at 10:42 in the morning, because the reference rate may have been set hours earlier or later.
Using the mid as a benchmark
The mid-market rate becomes valuable when you use it to measure the cost of each conversion. The method is the same every time.
- At the moment you book, record the mid-market rate from your chosen source and the time.
- Calculate the difference between your dealt rate and that mid.
- Multiply the difference by the amount to express it in currency.
- Divide the difference by the mid to express it as a percentage or in basis points.
Keep the results in a simple log. Over a few months you will see your typical cost by currency pair, by trade size and by time of day. That is a far better basis for a conversation with your provider than a single trade that went badly, and it lets you test claims made by other providers against your own history.
Some platforms show a benchmark alongside each quote. That is convenient, but it is still worth checking against an independent source from time to time.
Common benchmarking mistakes
The mid-market rate is easy to misuse. These are the errors that come up most often.
- Comparing across time. Checking the mid an hour after the trade, and complaining about the difference, measures market movement as well as cost.
- Using weekend figures. The wholesale market largely closes from Friday evening in New York to Monday morning in Asia. Rates shown at the weekend are stale and can gap when trading resumes.
- Ignoring quiet hours. In the early Asian morning, a European cross rate can have a wide wholesale spread, so a mid taken then is less reliable.
- Inverting the pair. A EUR/CAD rate of 1.5000 is a CAD/EUR rate of about 0.6667. Mixing the two produces nonsense.
- Forgetting the value date. A mid for spot value is slightly different from a mid for value today.
- Leaving out fees. The rate tells only part of the story if a separate fee is charged or deducted.
A worked example
This example uses hypothetical rates for illustration only.
A Hong Kong trading company sells EUR 400,000 of export receipts for US dollars. At the moment the treasurer books, the chosen data source shows EUR/USD at 1.0899 / 1.0901, a mid-market rate of 1.0900. The treasurer is selling euros, so the dealt rate is below the mid. The confirmed rate is 1.0860.
- Proceeds at the mid would have been 400,000 multiplied by 1.0900, which is USD 436,000.
- Actual proceeds are 400,000 multiplied by 1.0860, which is USD 434,400.
- The difference is USD 1,600.
- As a proportion of the mid-rate proceeds, 1,600 divided by 436,000 is about 0.37%, or roughly 37 basis points.
Whether that is a reasonable cost depends on the pair, the amount, the time of day and the service bundled with it. What the calculation gives the treasurer is a number that can be compared fairly with the next trade, with other providers and with the company's own history.
How far from the mid is normal
There is no fixed answer to how far from the mid a business should expect to deal, because the distance depends on conditions that change through the day. It is still possible to say which way the main factors push.
The width of the wholesale market around the mid is the starting point. In EUR/USD during the overlap of the London and New York trading days, the bid and offer sit very close together, so the mid is a tight and reliable reference. In a pair such as EUR/PLN, the wholesale market is deep during European hours and much thinner overnight. In a cross such as GBP/HKD, which is usually built from two other pairs, the market is wider still because it carries two spreads.
On top of that sits the provider's margin, which reflects ticket size, the payment work attached to the trade and the cost of serving the client. A small conversion with a payment to a new beneficiary in an unusual country involves more work than a large conversion paid to the client's own account.
The practical approach is to build your own baseline. Track the distance from the mid on your real trades for a few months, separated by currency pair and rough size band. Once you have that, a trade that sits well outside your own normal range is worth a question to your dealer. It may have a perfectly good explanation, such as a volatile market or an out-of-hours booking, and the conversation will tell you whether it did.
The mid and your accounts
Finance teams use mid or reference rates in two different places, and keeping them apart avoids confusion with auditors.
When a business translates foreign currency balances or the results of an overseas subsidiary for reporting, it typically uses a published rate, often a closing or average rate, applied consistently. That process does not involve any trade.
When a business actually converts money, it records the transaction at the rate it dealt. The difference between the dealt rate and any accounting rate shows up as a foreign exchange gain or loss. A loss on that line does not by itself mean the conversion was expensive. It may simply reflect market movement between the accounting date and the trade date. The mid at the time of booking is the right yardstick for conversion cost. The accounting rate is the right yardstick for reporting.
General information
This article is general information about the mid-market rate and benchmarking. It is not investment advice and does not recommend any course of action. Examples are hypothetical. CCYFX confirms the dealt rate for every trade in writing, giving you what you need to measure your costs against a benchmark of your choosing. Learn more on our foreign exchange page.
