A pegged exchange rate links a currency to another currency or basket at a stated parity or within a narrow range supported by official policy.
A pegged exchange rate links a currency to another currency or a currency basket at a stated parity or within a narrow range supported by official policy. The monetary authority may use foreign-exchange intervention, interest rates, domestic liquidity operations, fiscal coordination, or transaction rules to maintain that relationship.
A peg can reduce day-to-day exchange-rate volatility against the anchor, but it does not eliminate currency risk. Reserve pressure, inflation differences, capital flows, political decisions, and confidence can lead to tighter controls, a new parity, a wider band, or abandonment of the peg.
flowchart LR
A["Market demand and supply pressure"] --> B["Exchange rate moves toward weak or strong edge"]
B --> C["Monetary authority responds"]
C --> D["Buy or sell reserves"]
C --> E["Adjust rates or domestic liquidity"]
C --> F["Change controls, communication, or fiscal policy"]
D --> G["Rate returns toward parity or pressure continues"]
E --> G
F --> G
Suppose the rate is quoted as domestic-currency units per one anchor-currency unit. If the market pushes the quote above the permitted level, the domestic currency is weakening. To support it, the authority may sell anchor-currency reserves and buy domestic currency. Appreciation pressure creates the opposite transaction.
Intervention can affect the domestic money supply. The authority may sterilize that effect through other operations, but sterilization has costs and may not resolve the underlying pressure.
| Arrangement | Core feature | Main distinction |
|---|---|---|
| Conventional peg | Currency is maintained around a fixed parity to one currency or basket | Parity is intended to remain stable until formally changed |
| Currency board | Rule-based convertibility at a fixed rate with monetary constraints and reserve-backing requirements | Stronger institutional commitment than an ordinary peg |
| Exchange-rate band | Rate can move within published limits around a central rate | More permitted movement than a narrow conventional peg |
| Crawling peg | Parity is adjusted gradually by a schedule or indicator | Path changes through small repeated steps |
| Adjustable peg | Parity is fixed but can be realigned under the framework | Discrete adjustment rather than a regular crawl |
| Basket peg | Anchor value depends on multiple currencies | Reduces reliance on one anchor but adds weight and valuation complexity |
A country using another currency with no separate legal tender is a harder commitment than a conventional peg and should be classified separately.
An adjustable peg maintains a currency around a declared parity but permits the authority to reset that parity when the existing rate is no longer sustainable or appropriate under the framework. It combines short-run exchange-rate stability with the possibility of a discrete devaluation or revaluation.
The term is especially associated with the Bretton Woods system, whose par values were fixed but adjustable rather than permanent. A parity change was intended to address a fundamental disequilibrium, although identifying that condition and agreeing on the timing could be politically and economically difficult.
| Arrangement | How the reference rate changes | Main distinction |
|---|---|---|
| Conventional peg | Usually unchanged until an authority announces a new parity | The commitment may be adjustable in practice even if no schedule is stated |
| Adjustable peg | Reset through an occasional discrete realignment | Adjustment is infrequent and step-like |
| Crawling peg | Moved through small repeated changes under a rule or policy process | Adjustment is gradual rather than one large step |
| Exchange-rate band | Market rate moves within boundaries around a central rate | The permitted range and the central-rate adjustment rule are separate questions |
An adjustable peg does not guarantee a smooth transition. If market participants expect a devaluation, they may seek the anchor currency before the new parity is announced. That pressure can reduce reserves, raise domestic rates, widen forward discounts, increase parallel-market premiums, or lead to temporary controls.
When analyzing an adjustable peg, verify:
The worked example below shows the balance-sheet effect of a discrete reset from 4.00 to 5.00 domestic-currency units per anchor unit. That is an adjustable-peg realignment, not normal movement inside a band.
Assume a government-owned utility owes 50 million units of the anchor currency. Its revenue is domestic, and the peg is 4.00 domestic-currency units per anchor unit.
At the existing parity, the domestic-currency principal is:
50 million x 4.00 = 200 million.
Suppose authorities reset the parity to 5.00 domestic units per anchor unit. The direct quote rises by 25% because each anchor unit now costs one-fourth more domestic currency. Measured reciprocally, the domestic currency falls from 0.25 to 0.20 anchor units per domestic unit, a 20% devaluation in the domestic currency’s value.
The translated principal becomes:
50 million x 5.00 = 250 million.
The local-currency burden increased by 50 million, or 25%, before considering interest, fees, taxes, hedges, accounting rules, or changes in utility revenue. The anchor-currency amount did not change; the domestic-currency value did.
If the quote were inverted, the percentage interpretation would differ. Always record which currency is the numerator and denominator.
| Feature | Peg | Band | Managed float | Multiple-rate system |
|---|---|---|---|---|
| Public reference | Fixed parity or narrow relationship | Central rate plus boundaries | Fixed path not required | Different rates for transactions or users |
| Market movement | Limited around the peg | Permitted within the band | Broader, subject to intervention | Depends on each official or market segment |
| Main policy risk | Devaluation or abandonment | Realignment, widening, or break | Uncertain intervention response | Segmentation, access, and policy-rate changes |
| Main evidence | Parity rule and defense mechanism | Central rate and limits | Market behavior and intervention | Eligibility and applicable transaction rate |
A peg can coexist with capital controls or multiple exchange rates. The formal parity may govern one market while another rate applies to less-favored transactions.
Potential objectives include:
These are objectives, not guaranteed results. A peg does not automatically produce low inflation, fiscal discipline, trade growth, or investment inflows. If domestic policy is inconsistent with the parity, the apparent stability can delay rather than avoid adjustment.
Relevant evidence includes:
Gross reserves alone are not a complete adequacy measure. Some assets may be illiquid, pledged, borrowed, or offset by near-term foreign-currency obligations.
When capital is mobile, defending a peg limits how far domestic interest rates can diverge from those consistent with the currency commitment and expected adjustment. The Macroeconomic Trilemma summarizes the tension among a fixed exchange rate, open capital flows, and independent monetary policy.
The constraint is not absolute in every period. Controls, market frictions, risk premiums, sterilization, and credibility create room for temporary differences. But persistent conflict between the peg and domestic policy can produce reserve losses, rate pressure, restrictions, or realignment.
A peg can stabilize invoice conversion over short horizons. It does not guarantee that a bank will supply currency at the official rate or that settlement can occur without delay.
Stable rates can encourage unhedged foreign-currency borrowing. A devaluation can raise leverage, debt service, collateral pressure, and default risk for borrowers without matching foreign-currency income.
Forecasts based only on the parity can understate tail risk. Analysts may need unchanged-peg, modest realignment, severe break, and convertibility-delay scenarios.
Forward and option prices may incorporate rate differentials, liquidity, controls, and expected policy changes. A hedge can reduce specified exposure but create counterparty, collateral, basis, rollover, or settlement risk.
This article is for financial education only. It does not provide currency, trading, hedging, legal, accounting, tax, or investment advice.