Reykjavik to San Juan Time
GMT to AST Converter — 9 AM GMT is 5:00 AM AST
Reykjavik is 4 hours ahead of San Juan. Convert any time between Reykjavik (GMT) and San Juan (AST) instantly.
Reykjavik
Iceland
San Juan
Puerto Rico
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Time Zone Comparison
Reykjavik to San Juan Time Conversion Table
| Reykjavik (GMT) | San Juan (AST) |
|---|---|
| 12:00 AM | 8:00 PM |
| 2:00 AM | 10:00 PM |
| 4:00 AM | 12:00 AM |
| 6:00 AM | 2:00 AM |
| 8:00 AM | 4:00 AM |
| 10:00 AM | 6:00 AM |
| 12:00 PM | 8:00 AM |
| 2:00 PM | 10:00 AM |
| 4:00 PM | 12:00 PM |
| 6:00 PM | 2:00 PM |
| 8:00 PM | 4:00 PM |
| 10:00 PM | 6:00 PM |
Reykjavik & San Juan — Business & Scheduling Guide
Reykjavik (Iceland) is a small but highly connected Nordic island economy, with key industries in fishing, geothermal energy, tourism, and aluminum smelting. San Juan (Puerto Rico) is a US territory with pharmaceutical and tech manufacturing, known for pharmaceuticals, medical devices, electronics, and tourism. With a 4-hour time difference, professionals frequently schedule cross-border calls between these two cities for international trade, remote team collaboration, and client meetings.
Scheduling Meetings Between Reykjavik and San Juan
The 4-hour difference between Reykjavik and San Juan requires careful scheduling. The best overlap window is typically 2–4 hours when both cities are within working hours. Icelandic business hours are typically 9 AM–5 PM, with one of the world's highest internet penetration rates. Puerto Rican business hours are typically 8 AM–5 PM, with a bilingual (English/Spanish) workforce. Teams often designate specific "overlap hours" for real-time collaboration and use asynchronous communication (Slack, email, recorded video) for the rest of the day.
Daylight Saving Time Considerations
Neither Reykjavik nor San Juan observes Daylight Saving Time — Reykjavik stays on GMT and San Juan stays on AST year-round. This makes scheduling between these two cities simpler, as the 4-hour time difference remains constant throughout the year with no DST surprises.
Collaboration Tools & Workflow
The 4-hour gap between Reykjavik and San Juan means teams get roughly half a day of overlapping work hours. Successful cross-timezone teams typically batch synchronous activities (standups, reviews, planning) into the overlap window and reserve solo deep work for non-overlapping hours. Tools like Loom for async video updates, Slack with status indicators showing each team's local time, and shared Notion docs help bridge the gap. Many teams adopt a "follow-the-sun" workflow where handoffs happen at the edges of each team's workday.
Remote Work Between Reykjavik & San Juan
Reykjavik, a key city in Iceland, and San Juan, a key city in Puerto Rico, are well-connected for remote work. With a manageable 4-hour time difference, distributed teams can maintain a near-synchronous workflow. Both cities have strong internet infrastructure, coworking spaces, and established remote work cultures. For freelancers and remote workers, this time zone pairing is ideal — you can serve clients in San Juan from Reykjavik (or vice versa) without disrupting your standard workday.
GMT to AST — Quick Reference
GMT (GMT) stands for the timezone used in Reykjavik, Iceland (UTC+0). AST (AST) is the timezone used in San Juan, Puerto Rico (UTC-4). Reykjavik is 4 hours ahead of San Juan.
To convert GMT to AST, subtract 4 hours from GMT time. For example, GMT 9:00 AM = AST 5:00 AM.
Key Facts
- •Time difference: Reykjavik (UTC+0) is 4 hours ahead of San Juan (UTC-4).
- •Daylight Saving Time: Reykjavik does not observe DST (GMT). San Juan does not observe DST (AST).
- •Regions: Reykjavik is located in Iceland and uses the GMT time zone. San Juan is located in Puerto Rico and uses the AST time zone.
- •Best time to call: The best time to call between Reykjavik and San Juan is 1:00 PM to 4:00 PM in Reykjavik time, when both cities have overlapping standard working hours.
Frequently Asked Questions
What is the time difference between Reykjavik and San Juan?
Reykjavik is 4 hours ahead of San Juan.
What time is it in San Juan when it's 9 AM in Reykjavik?
When it's 9:00 AM in Reykjavik, it is 5:00 AM in San Juan.
What time is 9 PM GMT in AST?
9 PM GMT (Reykjavik time) is 5:00 PM AST (San Juan time). This is a common time people check when scheduling evening calls across these two time zones.
When is the best time to schedule a meeting between Reykjavik and San Juan?
The best time to schedule a meeting is between 1:00 PM to 4:00 PM in Reykjavik time, when both cities are within standard working hours (9 AM – 5 PM). This gives you the maximum overlap window for real-time collaboration.
How do I convert GMT to AST?
GMT (GMT) is the timezone for Reykjavik, Iceland (UTC+0). AST (AST) is the timezone for San Juan, Puerto Rico (UTC-4). Reykjavik is 4 hours ahead of San Juan. Quick examples: 9 AM GMT = 5:00 AM AST, 12 PM GMT = 8:00 AM AST, 3 PM GMT = 11:00 AM AST, 6 PM GMT = 2:00 PM AST.
Is Reykjavik ahead of or behind San Juan?
Reykjavik is 4 hours ahead of San Juan. When it's noon in Reykjavik, it's 8:00 AM in San Juan.
Does Reykjavik or San Juan change clocks for Daylight Saving Time?
No, Reykjavik does not observe DST — it stays on GMT year-round. San Juan does not observe DST — it stays on AST year-round.
What time is noon in Reykjavik in San Juan time?
When it is 12:00 PM (noon) in Reykjavik (GMT), it is 8:00 AM in San Juan (AST). This is often a popular time for scheduling lunch-hour calls across the Reykjavik–San Juan corridor.
What are the overlapping work hours between Reykjavik and San Juan?
The overlapping work hours between Reykjavik and San Juan are approximately 1:00 PM to 4:00 PM in Reykjavik time, when both cities are within the standard 9 AM–5 PM workday. This is the ideal window for meetings, pair programming, and real-time collaboration.
What timezone is Reykjavik in?
Reykjavik is in the GMT time zone (UTC+0). It is located in Iceland. Reykjavik does not observe Daylight Saving Time.
What timezone is San Juan in?
San Juan is in the AST time zone (UTC-4). It is located in Puerto Rico. San Juan does not observe Daylight Saving Time.
How do I schedule a call between Reykjavik and San Juan?
To schedule a call between Reykjavik and San Juan, aim for the overlapping window of 1:00 PM to 4:00 PM in Reykjavik time. Use Google Calendar or Calendly with both time zones visible, share the meeting invite with the AST time clearly noted, and always double-check the time difference — especially during DST transitions. Pro tip: include both local times in the calendar invite title (e.g., "Sync — 10 AM GMT / 6:00 AM AST").
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