Currency Risk in ETFs: Hedged or Unhedged? A Practical Guide

The index rose 8%. Your return was 1%

You check your MSCI World ETF at year end. The index, in dollars, gained 8%. You open your brokerage app and see a 1% return. There is no error and no hidden fee: in between sits the euro/dollar exchange rate, which moved against you over the same period and absorbed almost all of the gain.

This is currency risk, a source of return and volatility that most ETF investors carry without realizing it. It is not a flaw in the product or a tracking error: it is a structural feature of any ETF that invests in assets denominated in a currency other than your own. This guide explains what currency risk is, how large it can be, how hedged ETFs work, and when choosing a hedged share class actually makes sense.

What currency risk means for an ETF investor

When you buy an ETF that holds stocks or bonds denominated in dollars, yen, or pounds, your return in euros depends on two independent factors: the performance of the underlying asset in its own currency, and the change in the exchange rate between that currency and the euro.

In simple terms, the euro return of a dollar-denominated investment can be broken down as:

$$ R_{EUR} \approx R_{USD} + R_{EUR/USD} $$

where $R_{USD}$ is the return of the asset in dollars and $R_{EUR/USD}$ is the change in the exchange rate (how much the dollar gained or lost against the euro). If the dollar weakens against the euro while the index rises, part, or all, of the gain gets eaten away. If the dollar strengthens, your euro return can exceed the index return in its own currency.

The key point is this: an investor who buys an unhedged ETF tracking a US index is not just buying US equity exposure. They are also, implicitly, taking a long position in the dollar. For many investors this second exposure is not a deliberate choice, it is simply a side effect of the currency the underlying index happens to be denominated in.

How much dollar exposure is really inside an MSCI World ETF

The most common case for a European investor is an MSCI World ETF, the core holding of most lazy portfolios. Roughly 70% of the index’s market capitalization is US companies, priced and valued in dollars.

That means an investor holding an unhedged MSCI World ETF effectively has about 70% of their global equity allocation exposed to swings in the EUR/USD rate, on top of the equity risk itself. The remaining 30%, spread across Europe, Japan, the UK, and other markets, introduces smaller currency exposures of its own (yen, pound, Swiss franc), each behaving differently against the euro.

For an investor with a long time horizon, this dual exposure (equity and currency) is not necessarily a problem. But it is worth knowing about, because it is exactly this second component that currency-hedged ETFs are designed to neutralize.

How currency-hedged ETFs actually work

A hedged ETF tracks the same index as its unhedged counterpart, but adds a layer of financial contracts, typically currency forwards, designed to neutralize the effect of exchange rate movements on the euro value of the investment.

Simplified, the mechanism works like this:

1. The fund manager estimates the dollar (or other foreign currency) value of the underlying portfolio.
2. It sells that amount forward against euros, through a forward contract typically expiring monthly.
3. When the contract matures, it is closed and a new one is opened based on the updated value of the portfolio (monthly rolling).

The result is that EUR/USD movements are offset by gains or losses on the forward contract, leaving the euro return (in theory) close to the return of the index in its own currency.

In practice, the hedge is never perfect. Three factors create a residual gap, known as hedging tracking difference:

• A mismatch between the hedged notional and the actual portfolio value, which changes daily while the forward is only rebalanced periodically.
• Transaction costs from opening and closing forward contracts every month.
• Smaller, uncovered currency exposures, when the fund only hedges the main currency (e.g. the dollar) and leaves yen, pound, or Swiss franc exposure uncovered.

For this reason, a hedged ETF never eliminates 100% of currency risk: it reduces it substantially, typically to below 5% residual exposure, but not to zero.

What hedging actually costs

Currency hedging is not free, even though it does not appear as a separate line item in the fund’s TER. The cost comes from the interest rate differential between the two currencies involved, a mechanism known as covered interest rate parity.

Roughly speaking:

$$ \text{Hedging cost} \approx i_{USD} - i_{EUR} $$

where $i_{USD}$ and $i_{EUR}$ are short-term interest rates in the two currency areas. When US rates are higher than euro area rates, as has been the case for most of the 2022-2025 period, the hedging cost is positive: an investor buying the hedged share class implicitly pays the rate differential.

A numerical example helps illustrate the scale. Assume an annual rate differential of 1.8% between the dollar and the euro:

• An unhedged MSCI World ETF tracking an index that gains 9% in dollars, with a stable EUR/USD rate, returns roughly 9% in euros.
• The hedged version of the same ETF, over the same period, returns roughly 9% minus the 1.8% hedging cost, so about 7.2%.

This 1.8% is not a visible fee in the fund’s KID: it is an implicit cost that only shows up when comparing the two versions’ performance over time. When the rate differential narrows, or reverses (euro area rates exceed US rates), the hedging cost shrinks, or can even turn into a gain for holders of the hedged share class.

Hedged vs unhedged: the historical record

The most concrete way to grasp the impact of hedging is to compare two share classes of the same ETF over time. A classic example is the iShares Core MSCI World pair: the unhedged version (ticker IWDA) and the EUR-hedged version (ticker IWDE).

The structural point to remember is that, over long horizons, currency swings tend to be less persistent than equity swings: a strong dollar today does not imply a strong dollar for the next twenty years. For this reason, over multi-year horizons currency effects tend to partially average out on their own, an argument supporters of unhedged exposure often make.

Bonds are where hedging changes everything

If for equities the hedged-vs-unhedged choice is largely a matter of preference and time horizon, for bond ETFs the calculation is fundamentally different.

A government or corporate bond denominated in dollars typically has an annual price volatility in the range of 4-7%. The EUR/USD exchange rate, on its own, has historically had an annual volatility in the range of 7-10%. That means for an unhedged dollar bond ETF, currency risk can be larger than the bond’s own credit and interest rate risk: the currency “tail” can move the portfolio more than the bond “body” itself.

This is why global bond ETFs aimed at European investors are almost always offered in hedged form, often signaled by an “H” in the ticker, such as AGGH versus the unhedged version of the Bloomberg Global Aggregate index. An investor who buys a bond ETF for the defensive part of a portfolio, and ends up with volatility dominated by currency swings, has effectively defeated the purpose of that allocation.

Hedged or unhedged: a practical decision framework

There is no universal answer, but a few practical criteria help.

Lean toward unhedged if:

• Your investment horizon is long (10 years or more) and the allocation is mostly equity.
• You are comfortable with the extra currency volatility as part of overall portfolio diversification, considering that a strong dollar and weak markets tend to coincide (a “safe haven” effect that can cushion euro-denominated drawdowns).
• You want to avoid the implicit cost of hedging, especially when the rate differential is wide.

Lean toward hedged if:

• The allocation is bond-heavy, where currency risk threatens to dominate the instrument’s risk profile.
• Your investment horizon is short to medium (under 5-7 years), leaving less time for an adverse currency move to average out.
• You want the portfolio’s performance to track the underlying index as closely as possible, for example for analysis and comparison purposes.

A middle-ground approach used by some investors is to keep the equity sleeve unhedged (where currency risk dilutes over time and geographic diversification) and hedge the bond sleeve (where currency can otherwise overwhelm everything else). This mirrors how many lazy portfolios structure their equity-bond split.

How to spot a hedged ETF

Identifying whether an ETF is hedged is easier than it sounds once you know the conventions:

• The fund’s name almost always includes “(EUR Hedged)” or “(EUR Hdg)” for currency-hedged share classes.
• The ticker often carries a trailing or embedded “H”: for example IWDE (hedged) versus IWDA (unhedged) for the iShares Core MSCI World, or AGGH versus the unhedged version of the Bloomberg Global Aggregate Bond index.
• The KID (Key Information Document) explicitly states, in its investment policy section, whether the fund uses currency hedging instruments and on which exposures.

When in doubt, the KID is the definitive source: two ETFs with nearly identical names can have very different risk profiles if one is hedged and the other is not.

Next step

Currency risk is one of the least visible, yet most influential, components of a global portfolio’s composition. Understanding how much currency exposure you are actually carrying, and whether it fits your horizon and the role of each position, is part of properly analyzing your portfolio.

With Wallible you can:

• Analyze your portfolio’s composition and see how much exposure you have to the dollar, yen, and other currencies through the ETFs you hold
• Read the lazy portfolio guide to see how equity and bond components, hedged and unhedged, fit into a coherent allocation
• Explore ETF taxation in Italy to complete the picture on costs and tax treatment of the instruments you use