Eastern Standard Time (EST, UTC−5) and Central European Time (CET, UTC+1) are separated by 6 hours, defining the core scheduling gap between the US East Coast and continental Europe. This relationship covers one of the world’s busiest business corridors, connecting New York, Washington, and Boston with Paris, Berlin, Amsterdam, Milan, and dozens of other European capitals.

The 6-Hour Gap

CET is UTC+1 while EST is UTC−5, placing central Europe 6 hours ahead of the US East Coast. When New York is at 9 AM EST, it is already 3 PM in Paris and Frankfurt. When the NYSE closes at 4 PM EST, European exchanges have been shut for three hours (4 PM CET / 10 AM EST). The transatlantic overlap window for both sides to be within business hours is 3–6 PM CET (9 AM–12 PM EST) at the most generous reading.

In summer, EST becomes EDT (UTC−4) and CET becomes CEST (UTC+2). The gap remains 6 hours. However, because the US and EU transition clocks on different dates (US: second Sunday in March; EU: last Sunday in March), there is a 2–3 week window each spring when EST is still in effect but CET has become CEST, narrowing the gap to 5 hours. A similar window occurs in autumn.

Quick Conversion Reference

To convert EST to CET, add 6 hours. To convert CET to EST, subtract 6 hours.

The DST Transition Gap

The most common source of EST/CET scheduling errors is the brief window when the US and Europe have transitioned on different dates. In spring, the US typically springs forward in early-to-mid March while the EU transitions on the last Sunday of March. During this 2-3 week gap, New York has already moved to EDT (UTC−4) but Europe is still on CET (UTC+1). The gap is 5 hours, not 6.

The reverse happens in autumn: the EU falls back in late October, but the US does not fall back until the first Sunday of November. For that roughly one-week window, New York is still on EDT (UTC−4) while Europe has returned to CET (UTC+1). The gap again narrows to 5 hours.

Which Countries Use CET?

CET (UTC+1) is used by France, Germany, Italy, Spain, Portugal (no, Portugal uses WET/WEST, same as UK — it is one hour behind CET), the Netherlands, Belgium, Luxembourg, Austria, Switzerland, Liechtenstein, Monaco, San Marino, Vatican City, Poland, Czech Republic, Slovakia, Hungary, Slovenia, Croatia, Bosnia, Serbia, North Macedonia, Albania, and Kosovo. Sweden, Norway, and Denmark also use CET.

Notably, Spain and France are geographically aligned with Greenwich but use CET for historical and political reasons. This means Spanish and French solar noon is often at 1:30–2:30 PM local time, later than it would be in a zone matching their geography.