The euro (EUR)

What it is

The euro (ISO code EUR) is the official currency of the eurozone, a monetary union comprising 21 of the 27 EU member states. The European Central Bank (ECB), headquartered in Frankfurt, Germany, sets monetary policy for the entire zone. The Eurosystem, which is the ECB plus the 21 national central banks of euro-area states, executes those decisions. Six EU states retain their own currencies; five are formally obliged to adopt the euro once they meet convergence criteria, while Denmark holds a permanent opt-out negotiated in 1992. The euro floats freely; the ECB publishes daily reference exchange rates and does not target a bilateral rate.

History

The euro's legal basis is the Treaty of Maastricht, signed on 7 February 1992 and in force from 1 November 1993. The treaty mandated a three-stage path to Economic and Monetary Union. Stage 1, which began on 1 July 1990, freed capital flows among EU states. Stage 2, from January 1994 to December 1998, aligned central bank policies and created the European Monetary Institute, the ECB's predecessor. Stage 3 opened on 1 January 1999, when 11 member states irrevocably fixed their exchange rates to a new common unit and delegated monetary policy to the ECB. Greece joined in 2001. Physical notes and coins replaced national currencies, including the Deutsche Mark, French franc, and Italian lira, on 1 January 2002. Subsequent accession rounds brought membership to 21, with Croatia joining most recently in January 2023. Each new member must demonstrate sustained convergence on four criteria: inflation within 1.5 percentage points of the EU's three best performers, a fiscal deficit below 3% of GDP, government debt below 60% of GDP, and exchange-rate stability for at least two years.

Current state

As of mid-2026, the euro is legal tender for approximately 350 million people. The ECB's June 2026 international-role report found the euro holds about 20% of global official foreign exchange reserves, making it the second most important reserve currency after the US dollar, which holds approximately 57%. International debt issuance denominated in euros reached a record above USD 1.1 trillion in 2025, the highest level since the currency's creation in 1999. For the first time, the euro also surpassed the US dollar as the leading currency in green and sustainable bond markets. Foreign portfolio inflows into euro-denominated assets approached EUR 850 billion in 2025, near historical peaks. On the policy side, the 欧央行因伊朗引发的能源冲击加息，2023年以来首次 saw the ECB raise its deposit rate to 2.25% in June 2026, the first hike since 2023, as energy-driven inflation projections for the eurozone climbed to 3.0%.

Relationships

The euro's trajectory is inseparable from ECB leadership and EU fiscal rules. Christine Lagarde, ECB president since November 2019, has navigated the post-pandemic tightening cycle and the recalibration described in 拉加德在辛特拉：欧央行转向"框架指引"，终结前瞻指引时代, which adjusted how the ECB anchors its neutral rate assessment. The ECB's decisions flow through commercial bank lending rates, government bond yields, and the EUR/USD exchange rate, affecting EU exporters and importers of dollar-priced commodities. EU fiscal governance under the Stability and Growth Pact, with its 3% deficit and 60% debt ceilings, sets the conditions for continued membership without triggering European Commission action. The euro's primary competition for global invoicing and bond denomination comes from the US dollar. Full euro-area institutional detail is in the ECB dossier.

What to watch

The euro's reserve share has held broadly stable at around 20% despite a roughly 2-percentage-point decline in the currency's share of global foreign exchange trading since 2022, a divergence the ECB attributes to shifting market microstructure rather than a loss of confidence. The ECB is developing a digital euro, a retail central bank digital currency for the eurozone that would sit alongside physical notes and coins, with design decisions expected in 2026 and 2027. EU enlargement, with Ukraine and Moldova holding candidate status as of mid-2026, would eventually add large economies to the euro's adoption pipeline, raising questions about the pace of convergence and the ECB's capacity to manage a structurally more diverse zone. The ECB's path back toward a neutral policy rate after the June 2026 hike will be the primary market focus for euro-denominated assets through the remainder of 2026.