Current Time in UTC-4 Zone
About UTC-4
Discover all countries and IANA time zones in the UTC-4 offset. View the current local time for all locations with this UTC offset.
UTC Offset: UTC-4
What is UTC-4?
UTC-4 is a fixed offset from Coordinated Universal Time: clocks on this offset are always 4 hours behind UTC. Unlike a named time zone, a UTC offset never shifts for daylight saving time. Regions that observe DST alternate between two different UTC offsets across the year, which is why the countries listed below can change with the seasons.
In aviation, shipping, and military usage, UTC-4 corresponds to the Quebec time zone (Q), written with the letter suffix Q in Zulu notation. Pilots and NATO forces use these letter zones so an order like "0800Q" is unambiguous worldwide.
UTC-4 vs GMT-4
On a wall clock, UTC-4 and GMT-4 show the same time. The difference is in what they refer to: UTC is the modern standard kept by atomic clocks and used in computing, aviation, and science, while GMT is the older convention based on mean solar time at Greenwich. Technical systems, logs, and APIs should reference UTC-4.
Time & Daylight in UTC-4
Time Difference Between UTC-4 and Major Cities
Live local time and the difference from UTC-4 right now.
Current time shown is based on the representative IANA zone: America/Anguilla
UTC-4: The Atlantic Standard Time Offset
UTC-4 is a fixed time offset that places clocks four hours behind Coordinated Universal Time. Unlike named time zones, which may shift for daylight saving time (DST), UTC-4 itself never changes. However, regions that observe DST move onto this offset during their summer months and off it in winter, meaning the list of countries and territories at UTC-4 is not static throughout the year. This article explores the geography, practical scheduling, and common questions about UTC-4.
Fixed Offset vs. Named Time Zone
A fixed UTC offset, such as UTC-4, is a constant number of hours behind UTC. It does not observe DST. In contrast, a named time zone like Atlantic Standard Time (AST) is defined by its standard offset (UTC-4) but may include DST rules that shift the offset to UTC-3 during summer. When a region observes DST, its clocks are set to UTC-4 only during the standard time portion of the year. Thus, the set of places at UTC-4 changes seasonally.
Regions and Cities Permanently at UTC-4
Several territories in the Caribbean and South America use UTC-4 year-round, with no DST. These include: Anguilla, Antigua and Barbuda, Aruba, Barbados, Bolivia, Bonaire, Curaçao, Dominica, Grenada, Guadeloupe, Guyana, Martinique, Montserrat, Puerto Rico, Saba, St. Barthélemy, St. Eustatius, St. Kitts and Nevis, St. Lucia, St. Maarten (Dutch), St. Martin (French), St. Vincent and the Grenadines, Trinidad and Tobago, the U.S. Virgin Islands, and Venezuela. Key cities in this group are Caracas (Venezuela), La Paz (Bolivia), San Juan (Puerto Rico), and Georgetown (Guyana).
Regions That Move onto UTC-4 Seasonally
Many places in Canada and the Caribbean observe DST and are at UTC-4 only during their standard time (winter) months. These include: Bermuda, Greenland (some areas), and most of the Atlantic Canada provinces: New Brunswick, Nova Scotia, Prince Edward Island, and parts of Newfoundland and Labrador (the Labrador region south of the Strait of Belle Isle uses UTC-4). In the Caribbean, the Bahamas, Cuba, Haiti, the Dominican Republic, and the Turks and Caicos Islands also use UTC-4 during standard time. During DST, these regions shift to UTC-3. Representative cities at UTC-4 during winter are Halifax (Nova Scotia), Hamilton (Bermuda), and Santo Domingo (Dominican Republic).
Brazilian States at UTC-4
Several states in Brazil use UTC-4 year-round: Amazonas (except its westernmost areas), Rondônia, Roraima, Mato Grosso, Mato Grosso do Sul, and parts of Pará (western). Key cities include Manaus, Cuiabá, Campo Grande, and Boa Vista. Note that Brazil no longer observes DST, so these offsets are constant.
Military and Aviation Designation
In military and aviation timekeeping, UTC-4 is designated by the letter Q (Quebec). This is part of the NATO phonetic alphabet used for time zone identification. For example, 14:00 UTC is 10:00 Q. While UTC and GMT are technically different (GMT is a time zone, UTC is a standard), they read the same on clocks. For practical purposes, UTC-4 is equivalent to GMT-4.
Practical Scheduling Notes
When scheduling across UTC-4, be aware of DST transitions in regions that observe it. For example, a meeting with someone in Halifax (Canada) will be at UTC-4 in winter but UTC-3 in summer. Meanwhile, a contact in Puerto Rico remains at UTC-4 year-round. The offset is commonly used for financial markets in the Caribbean and for coordinating with Eastern Time (UTC-5 standard, UTC-4 DST) during summer. Always confirm the local DST rules for the specific city.
Frequently Asked Questions
What does UTC-4 mean in simple terms?
UTC-4 means the local time is four hours behind Coordinated Universal Time (UTC). For example, when it is 12:00 UTC, it is 08:00 in a UTC-4 region.
Is UTC-4 the same as Atlantic Standard Time (AST)?
Yes, during standard time, Atlantic Standard Time is UTC-4. However, AST may also refer to a time zone that observes DST, shifting to UTC-3 in summer. So UTC-4 is the fixed offset, while AST can have seasonal variation.
Which major cities are always at UTC-4?
Major cities permanently at UTC-4 include Caracas (Venezuela), San Juan (Puerto Rico), Manaus (Brazil), La Paz (Bolivia), and Georgetown (Guyana).
Does any part of the United States use UTC-4?
Yes, Puerto Rico and the U.S. Virgin Islands are permanently at UTC-4. Additionally, the easternmost parts of the U.S. (like parts of Maine) are geographically near UTC-4 but use Eastern Time (UTC-5 standard, UTC-4 DST).
How does UTC-4 relate to Eastern Time?
Eastern Standard Time (EST) is UTC-5, so UTC-4 is one hour ahead of EST. During Eastern Daylight Time (EDT), Eastern Time is also UTC-4, so they align. This means when New York is on EDT, it shares the same offset as Puerto Rico.
What is the military letter for UTC-4?
The military letter for UTC-4 is Q (Quebec). It is used in aviation and military operations to denote this offset.