How central bank rates affect exchange rates

A central bank doesn’t set an exchange rate. It sets a price for money, the interest rate it pays or charges banks, and the exchange rate is one of the many things that price knocks into. The link is real, it is one of the main influences on a floating currency, and it is also regularly misdescribed as “higher rates, stronger currency, end of story.”

The story has a few more links in the chain. Follow them one at a time and the exceptions stop looking like exceptions.

Link one: the policy rate becomes everyone’s rate

Start in the United States. The Federal Reserve describes the federal funds rate, the rate banks pay each other for overnight borrowing, as its primary tool. It doesn’t dictate what your savings account pays. But changes in that rate move other interest rates, which changes what households and businesses pay to borrow.

Other central banks work the same general way, with their own names for it. The Bank of England calls its version Bank Rate. The European Central Bank, the Bank of Japan and the Reserve Bank of India each have theirs.

The Fed is careful about one thing, and it matters later. Its own explainer says the connections from monetary policy to inflation and jobs are “not direct or immediate.” Policy works through the economy slowly. Currency markets do not wait.

Link two: higher returns attract foreign money

Here is the part that touches exchange rates. Suppose a country’s central bank raises its rate. Bank deposits, short-term government bonds and similar holdings now pay more than they did. A fund manager in another country looks at that and asks a sensible question: can I earn more by holding that currency?

To buy the bonds, the manager first has to buy the currency. That is extra demand, and extra demand pushes the price up. The Bank of England’s explainer describes the same effect for sterling. A rise in Bank Rate usually lifts the pound, it says, since investors chasing the better UK return want more of it.

Notice the direction of the cause. The interest rate doesn’t move the exchange rate directly. It changes what people want to hold, and their buying does the moving.

A worked example, with made-up numbers

Everything here is illustrative. Two imaginary currencies, A and B. One unit of A costs 2.00 units of B. An investor holds 10,000 B. A one-year deposit in country A pays 5%. A one-year deposit in country B pays 1%.

If the investor stays home, the year ends with 10,100 B (10,000 times 1.01). If they move, three things happen in sequence:

1. They sell 10,000 B and buy 5,000 A at 2.00.
2. The deposit grows by 5%, to 5,250 A.
3. After a year they convert back at whatever the rate is then.

Step three is where it gets interesting. The investor needs at least 10,100 B to beat staying home. Divide 10,100 by 5,250 and you get 1.9238. So the break-even rate is about 1.9238 B per A. That means currency A can fall by about 3.8% against B, from 2.00 to 1.9238, and the investor is exactly as well off as if they’d never bothered.

That break-even is the point. The extra interest is compensation for the risk that the currency drops. In theory, markets bid up currency A until the extra return on offer looks about fair for the risk. Notice that the 4-point interest gap (5% against 1%) and the 3.8% break-even fall are close but not identical, because compounding and the direction you measure from both change the decimals.

Whether real currencies fall by exactly this much is a long-running argument among economists, and nobody has a tidy answer. In practice the fall can come late, early, or not at all, and a currency that keeps its value for a year hands the investor the full extra interest. A sharp fall in one bad month hands it all back.

Think of it as two queues. One queue wants the currency because of the yield. The other is made of people who would sell it at the first sign of trouble. The exchange rate at any moment is where those queues meet, and a rate decision mostly changes how long each queue is.

Expectations matter more than the decision

Return to the Fed’s warning that policy works slowly. Currency traders respond to what they expect a central bank to do over the next year, not what it did this morning. So the currency often moves when the expectation changes: after a speech, an inflation report, a surprising jobs figure.

By decision day, a widely forecast rate rise is already in the price. If the bank raises rates exactly as predicted, the currency may barely twitch. If it raises less than hoped, the currency can fall, even though rates went up. That feels backwards until you remember that the market had priced in more.

What matters, then, is a gap: the difference between one country’s rates (and expected rates) and another’s. When the New York Fed reviewed the second quarter of 2022, it reported the dollar rising sharply, 11.5% against the Japanese yen, 7.9% against the pound and 5.6% against the euro, and it pointed to wide interest rate differentials in favor of the United States, along with expectations that the Fed would raise rates faster to fight high US inflation. It was one explanation among several, as growth worries were also spreading. Rates helped, but they didn’t act alone.

When the pattern fails

Higher rates sometimes come with a weaker currency. A few reasons turn up repeatedly.

First, rates may be rising because inflation is out of control, and a high rate that still sits below inflation pays investors a negative return in real terms. Second, a rate rise that threatens to tip an economy into recession may be read as bad news rather than good. Third, other forces can overwhelm the interest effect, such as a sudden flight toward whichever currency investors treat as a safe place.

And the reverse can hold. A cut can leave a currency stable if the market feared a deeper cut. Nobody gets this right every time, including the professionals, and anyone promising a rule that always works is describing a rule that hasn’t been tested honestly.

What this means for your transfers

If a central bank you follow is expected to change rates soon, rates between your two currencies can shift around the announcement. You may see a bigger move on the day than a normal Tuesday. A sender with a deadline can’t do much about it. A sender with flexibility could check the meeting dates, which many central banks publish in advance, and avoid leaving a large conversion to the minutes around one.

You can follow the pairs most tied to rate decisions on USD to JPY or EUR to USD, and see the dollar against everything at once on the US dollar page. Rates refreshed hourly.

One honest caution. Trying to time a conversion around central banks is a bet, not a method. Your fee and the margin on the rate usually cost you more, with certainty, than a rate decision might cost or save you by chance. If the amount is large, ask your provider or a qualified adviser about your options.

Sources

• Who sets exchange rates? (Bank of England)
• How does the Federal Reserve affect inflation and employment? (Federal Reserve Board)
• Foreign exchange operations report, second quarter 2022 (Federal Reserve Bank of New York)

Checked: November 2026