Forex Central Banks & Interest Rates

A central bank manages a country's money: it sets the main interest rate, controls the money supply and tries to keep inflation stable. Central banks are the single most powerful force in the forex market.

What Does a Central Bank Do?

Every major currency has a central bank behind it. Its main tool is the policy rate (also called the base rate or benchmark rate): the interest rate at which banks borrow and lend overnight. That rate flows through to mortgages, loans, savings accounts and — importantly for us — to the return you earn for holding a currency.

Sets the policy interest rate.
Buys or sells bonds to add or remove money from the system (QE and QT).
Guides expectations through statements and speeches.
Sometimes buys or sells its own currency directly (intervention).

The Major Central Banks

Central bank	Currency	Decision body	Meetings per year	Inflation target
Federal Reserve (Fed)	USD	FOMC	8	2% (PCE)
European Central Bank (ECB)	EUR	Governing Council	8	2% (symmetric)
Bank of England (BoE)	GBP	Monetary Policy Committee	8	2% (CPI)
Bank of Japan (BoJ)	JPY	Policy Board	8	2%
Swiss National Bank (SNB)	CHF	Governing Board	4 (quarterly)	0–2%
Reserve Bank of Australia (RBA)	AUD	Monetary Policy Board	8	2–3%
Reserve Bank of New Zealand (RBNZ)	NZD	Monetary Policy Committee	7	1–3% (2% midpoint)
Bank of Canada (BoC)	CAD	Governing Council	8	2% (1–3% range)

Note: Dates are published a year in advance on each bank's website and on any economic calendar. Policy rates change often, so always check the current level rather than relying on a textbook.

Mandates: What Each Bank Must Achieve

A mandate is the goal set for the bank by law or by government.

Fed — dual mandate: maximum employment and stable prices. Jobs data matters as much as inflation.
ECB, BoE, BoC, RBNZ: price stability first (inflation near target), while supporting growth.
RBA: price stability and full employment.
BoJ: price stability; it spent decades fighting deflation (falling prices) and only ended negative rates in 2024.
SNB: price stability; it also watches the franc closely because a too-strong CHF hurts Swiss exporters.

Rate Hikes and Rate Cuts

Rates are moved in basis points (bps). 1 basis point = 0.01%, so 25 bps = 0.25%.

Rate Hike

Raising rates fights inflation. Saving in that currency pays more, so foreign money flows in.

Usual effect: currency strengthens.

Rate Cut

Cutting rates supports a weak economy. Holding that currency pays less, so money flows out.

Usual effect: currency weakens.

Warning: Markets react to the decision versus expectations. If traders expected a 50 bp hike and get only 25 bps, the currency can fall on a hike. Always know the consensus forecast before the announcement.

Interest Rate Differentials

The interest rate differential is the gap between two countries' rates. Because forex is traded in pairs, the differential is what really matters. Money tends to flow toward the currency whose rate is higher, or whose rate is expected to rise faster.

Differential = Rate of base currency − Rate of quote currency

Example

Hypothetical rates: the US policy rate is 4.00%, Japan's is 0.75%.

USD/JPY differential = 4.00% − 0.75% = 3.25% in favour of USD

Holding dollars instead of yen earns about 3.25% a year more. This is the basis of the carry trade. If the gap is expected to narrow (the Fed cuts, the BoJ hikes), USD/JPY tends to fall.

Tip: Watch the 2-year government bond yield gap between two countries. It reflects where traders think rates are heading and often moves in step with the currency pair.

Hawkish vs Dovish

	Hawkish	Dovish
Focus	Fighting inflation	Supporting growth and jobs
Rate bias	Hike or hold high	Cut or hold low
Typical words	"vigilant", "further tightening", "inflation remains too high"	"patient", "downside risks", "room to ease"
Usual currency effect	Stronger	Weaker

A hawkish surprise is when the bank sounds tougher than expected. A dovish surprise is the opposite. Even with no change in rates, a shift in tone can move a pair 50–100 pips.

QE, QT and Forward Guidance

Quantitative Easing (QE)

When rates are already near zero, a central bank can create new money and buy government bonds. This pushes long-term interest rates down and adds money to the system. QE is dovish and usually weakens the currency.

Quantitative Tightening (QT)

The reverse: the bank lets bonds mature without replacing them, or sells them. Money is removed from the system. QT is hawkish.

Forward Guidance

Forward guidance is the bank telling markets what it is likely to do next. Examples: "rates will stay at this level for some time" or the Fed's quarterly "dot plot" of members' rate forecasts. Because markets trade expectations, guidance can move a currency more than the decision itself.

How to Read a Rate Decision

Before: Note the consensus forecast and what the market is pricing (shown by rate futures or "market-implied probabilities").
The decision: Hike, cut or hold? Was it the expected size?
The statement: Compare the wording to the last one. New hawkish or dovish words matter.
The vote split: e.g. a BoE vote of 5–4 to hold shows the committee is close to changing.
Projections: New forecasts for inflation, growth and rates (e.g. the Fed's dot plot).
Press conference: The governor or chair's answers often cause a second, bigger move.

Illustration: GBP/USD 15-minute chart around a Bank of England decision. Price is quiet before the announcement, jumps on a hawkish surprise, wobbles, then extends higher during the press conference.

Danger: Spreads widen and slippage is common in the seconds after a decision. Many traders stay flat into the announcement and trade the reaction afterwards. See Trading the News.

Currency Intervention

Intervention is when a government or central bank buys or sells its own currency directly to change its value. It is rare but powerful.

Japan: The Ministry of Finance (acting through the BoJ) sold dollars and bought yen in 2022 and again in 2024, when USD/JPY was near 145–160. Moves of 300–500 pips in hours followed.
Switzerland: The SNB held a floor of 1.20 under EUR/CHF from 2011. When it removed the floor without warning on 15 January 2015, the franc jumped about 30% in minutes, and some brokers went bankrupt.
Verbal intervention: Officials warn they are "watching the currency closely". This is often a first step before real action.

Warning: Intervention can move price hundreds of pips with no warning. If officials are issuing warnings about a currency, trade smaller and always use a stop loss.

Test Yourself With Exercises

Which central bank has a dual mandate of maximum employment and stable prices?

European Central Bank
Swiss National Bank
Federal Reserve
Bank of Japan

The Federal Reserve has a dual mandate: maximum employment and stable prices.

A central bank raises rates by 50 basis points. What is that in percent?

0.50%
5.0%
0.05%

1 bp = 0.01%, so 50 bps = 0.50%.

Australia's rate is 3.60% and Canada's is 2.25%. What is the AUD/CAD interest rate differential?

5.85% in favour of CAD
1.35% in favour of AUD
1.35% in favour of CAD

3.60% − 2.25% = 1.35% in favour of AUD, the base currency.

A central bank says inflation "remains too high" and further tightening "may be needed". How is this best described?

Dovish
Neutral
Quantitative easing
Hawkish

Talk of fighting inflation and more tightening is hawkish, usually supportive for the currency.

The market expects a 50 bp hike, but the bank hikes only 25 bps. What is the most likely reaction?

The currency rises strongly — rates went up
The currency falls — the result was less hawkish than expected
No reaction — rate decisions do not matter

Markets trade the surprise. A smaller hike than expected is a dovish surprise, so the currency often falls.