Amazon Time (AMT)

Amazon Time (AMT) operates at UTC−4 hours and is used across much of Brazil's North and Central-West regions, including most of Amazonas state (such as Manaus), as well as Mato Grosso, Mato Grosso do Sul, Rondônia, and Roraima. Sometimes called "Amazon Standard Time," AMT does not observe daylight saving time and stays consistent year-round.

Importance and Global Use of AMT

AMT is crucial for supporting daily life and economic activities across a vast portion of the Brazilian Amazon and agricultural regions. Its stable UTC−4 offset helps coordinate transportation, education, public services, and business operations in these areas, which often have limited infrastructure and rely on consistent scheduling.

Internationally, AMT connects Brazil's interior regions with global trade routes, aviation networks, and environmental research programs. Its predictable timekeeping is important for cross-border cooperation, scientific studies, and sustainable development efforts in the Amazon basin and surrounding areas.

Where and When AMT is used worldwide

South America

Brazil states using AMT all year:

• Amazonas - most of the state, including Manaus, the capital (southwestern region observe ACT instead)
• Mato Grosso
• Mato Grosso do Sul
• Rondônia
• Roraima

Other Time Zones in UTC -4

Other time zones share the same offset as Amazon Time (AMT), but are known by different names. While their clocks align, they may represent different regions or countries based on local time zone definitions.

• Atlantic Standard Time – AST
• Bolivia Time – BOT
• Cuba Daylight Time – CDT
• Chile Standard Time – CLT
• Eastern Daylight Time – EDT
• Guyana Time – GYT
• Venezuelan Standard Time – VET