Istanbul PortsmouthTime Converter
Istanbul (GMT+3, UTC+3) is currently 7 hours ahead of Portsmouth (AST, UTC−4). Compare live clocks, convert any hour, and find times to meet.
Quick answer
When it's in Istanbul, it's the same day in Portsmouth.
Istanbul (GMT+3) runs 7 hours ahead of Portsmouth (AST). Both sides keep standard office hours with a real 9–6 overlap — the highlighted window below works for everyone.
- Time difference
- −7h 00m
- Istanbul
- UTC+3
- Portsmouth
- UTC−4
- Best call window
- 4:00 PM GMT+3
Istanbul to Portsmouth conversion table
The next 12 hours in Istanbul and the matching local time in Portsmouth. The current hour is highlighted; drag the converter's slider and the table follows.
| Istanbul · GMT+3 | Portsmouth · AST |
|---|---|
| NOW Mon, Jul 27 |
Mon, Jul 27 |
Tue, Jul 28 |
Mon, Jul 27 |
Tue, Jul 28 |
Mon, Jul 27 |
Tue, Jul 28 |
Mon, Jul 27 |
Tue, Jul 28 |
Mon, Jul 27 |
Tue, Jul 28 |
Mon, Jul 27 |
Tue, Jul 28 |
Mon, Jul 27 |
Tue, Jul 28 |
Mon, Jul 27 |
Tue, Jul 28 |
Tue, Jul 28 |
Tue, Jul 28 |
Tue, Jul 28 |
Tue, Jul 28 |
Tue, Jul 28 |
Tue, Jul 28 |
Tue, Jul 28 |
Best time to meet between Istanbul & Portsmouth
Working hours are 9am–6pm in each city. The bright band is where they overlap: both sides at their desks.
This time difference never changes
Neither side observes daylight saving against the other, so the gap stays constant all year. Istanbul does not observe daylight saving time. Portsmouth does not observe daylight saving time. This page always shows the live, DST-aware difference.
Related time zone conversions
Jump straight to another pair: every combination is a live tool, not an article.
From Istanbul
To Portsmouth
One source of truth, for you and your AI
This page exposes the same answer as structured data, so when you ask an assistant "what's 9am Istanbul time in Portsmouth?", it can cite the exact, DST-aware result, not a stale blog post.
- Schema.org JSON-LD on every converter page
- A machine-readable facts island with time zone identifiers and every possible offset
- Live times in <time datetime> elements with explicit UTC offsets
{
"pair": "Istanbul → Portsmouth",
"url": "https://worldclock.pro/en/convert/istanbul-to-portsmouth-dm",
"from": {
"name": "Istanbul",
"type": "city",
"abbreviation": "GMT+3",
"daylightAbbreviation": null,
"iana": "Europe/Istanbul",
"standardUtcOffset": "+03:00",
"daylightUtcOffset": null,
"referenceCity": "Istanbul"
},
"to": {
"name": "Portsmouth",
"type": "city",
"abbreviation": "AST",
"daylightAbbreviation": null,
"iana": "America/Dominica",
"standardUtcOffset": "-04:00",
"daylightUtcOffset": null,
"referenceCity": "Portsmouth"
},
"currentDifferenceMinutes": -420,
"possibleDifferencesMinutes": [
-420
],
"note": "The difference is constant year-round."
}
Frequently asked questions
What is the time difference between Istanbul and Portsmouth?
Istanbul is currently 7 hours ahead of Portsmouth. Istanbul is on GMT+3 (UTC+3) and Portsmouth is on AST (UTC−4). The difference can change when either side starts or ends daylight saving time.
Is Portsmouth ahead of or behind Istanbul?
Portsmouth is currently 7 hours behind Istanbul.
When it is 9:00 AM in Istanbul, what time is it in Portsmouth?
When it is 9:00 AM on a Monday in Istanbul, it is 2:00 AM in Portsmouth.
Do Istanbul and Portsmouth observe daylight saving time?
Istanbul does not observe daylight saving time. Portsmouth does not observe daylight saving time.
How do I convert Istanbul time to Portsmouth time?
Subtract 7 hours from any time in Istanbul to get the time in Portsmouth. This page's converter and 24-hour table do it automatically and stay correct through daylight-saving changes.
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