Mumbai PortsmouthTime Converter
Mumbai (IST, UTC+5:30) is currently 9 hours 30 minutes ahead of Portsmouth (AST, UTC−4). Compare live clocks, convert any hour, and find times to meet.
Quick answer
When it's in Mumbai, it's the previous day in Portsmouth.
Mumbai (IST) runs 9 hours 30 minutes ahead of Portsmouth (AST). A 9-to-5 workday on one side lands in the other side's evening or night, so the two cities share almost no normal working hours — edge-of-day calls are the trick.
- Time difference
- −9h 30m
- Mumbai
- UTC+5:30
- Portsmouth
- UTC−4
- Best call window
- Outside 9–6
Mumbai to Portsmouth conversion table
The next 12 hours in Mumbai and the matching local time in Portsmouth. The current hour is highlighted; drag the converter's slider and the table follows.
| Mumbai · IST | Portsmouth · AST |
|---|---|
| NOW 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 |
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 |
Best time to meet between Mumbai & 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. Mumbai 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 Mumbai
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 Mumbai 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": "Mumbai → Portsmouth",
"url": "https://worldclock.pro/en/convert/mumbai-to-portsmouth-dm",
"from": {
"name": "Mumbai",
"type": "city",
"abbreviation": "IST",
"daylightAbbreviation": null,
"iana": "Asia/Kolkata",
"standardUtcOffset": "+05:30",
"daylightUtcOffset": null,
"referenceCity": "Mumbai"
},
"to": {
"name": "Portsmouth",
"type": "city",
"abbreviation": "AST",
"daylightAbbreviation": null,
"iana": "America/Dominica",
"standardUtcOffset": "-04:00",
"daylightUtcOffset": null,
"referenceCity": "Portsmouth"
},
"currentDifferenceMinutes": -570,
"possibleDifferencesMinutes": [
-570
],
"note": "The difference is constant year-round."
}
Frequently asked questions
What is the time difference between Mumbai and Portsmouth?
Mumbai is currently 9 hours 30 minutes ahead of Portsmouth. Mumbai is on IST (UTC+5:30) 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 Mumbai?
Portsmouth is currently 9 hours 30 minutes behind Mumbai.
When it is 9:00 AM in Mumbai, what time is it in Portsmouth?
When it is 9:00 AM on a Tuesday in Mumbai, it is 11:30 PM the previous day in Portsmouth.
Do Mumbai and Portsmouth observe daylight saving time?
Mumbai does not observe daylight saving time. Portsmouth does not observe daylight saving time.
How do I convert Mumbai time to Portsmouth time?
Subtract 9 hours 30 minutes from any time in Mumbai 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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