Technical Specifications & Standards
Official chronometric properties, ISO standards, and international database registry identifiers for Paraguay Time:
Daylight Saving Time (DST) Transitions
⬆️ Spring Forward (Clocks Advance)
First Sunday in October at 24:00 / midnight (Clocks advance to PYST)
⬇️ Fall Back (Clocks Return)
Fourth Sunday in March at 24:00 / midnight (Clocks return to PYT)
Observing Jurisdictions & Subdivisions
1 Sovereign NationsSovereign nations, administrative subdivisions, and regional territories officially operating under PYT:
Regional Subdivisions & Territory Details
Financial Markets & Trading Hours
Asunción financial operations interface closely with agribusiness clearing systems in Buenos Aires, São Paulo, and global soybean import terminals.
Local Hours: 09:00 - 15:00 PYT
UTC Window: 13:00 - 19:00 UTC
Major Cities in PYT
Primary metropolitan centers and financial hubs observing this time zone:
Adoption History & Astronomical Facts
Year Established: 1931
First introduced in 1931 and codified into law under multiple presidential decrees to maximize solar light for agriculture. In 2023, the National Congress enacted Law No. 7111 to establish stable, predictable transition dates on the fourth Sunday of March and first Sunday of October.
At the Triple Frontier where Paraguay, Brazil, and Argentina meet at the confluence of the Iguazu and Paraná rivers, walking across the Friendship Bridge between Ciudad del Este and Foz do Iguaçu can require changing your watch by an hour during Paraguay's winter standard time.
Frequently Asked Questions about PYT
What is the difference between PYT and PYST?
PYT (Paraguay Time, UTC-4) is the winter standard time observed between March and October. PYST (Paraguay Summer Time, UTC-3) is the daylight saving offset used during the Southern Hemisphere summer between October and March.
On which days does Paraguay change its clocks?
Under Law No. 7111, Paraguay sets clocks forward by one hour on the first Sunday of October at midnight, and sets clocks back by one hour on the fourth Sunday of March at midnight.
Does Paraguay have the same time as Argentina and Brazil?
During summer (PYST, UTC-3), Paraguay has the same time as Argentina and São Paulo, Brazil. During winter (PYT, UTC-4), Paraguay is one hour behind Argentina and southeastern Brazil.