United Kingdom to Iran
+2h 30mUnited Kingdom
BSTSOURCEIran
IRSTGreen rows indicate typical business hours (9 AM - 5 PM)
BST and IRST on the World Map
The map below highlights the BST (Greenwich Mean Time) and IRST (Iran Standard Time) timezone regions across the globe.
GMT – Greenwich Mean Time
UTC+00:00Greenwich Mean Time (GMT) is the mean solar time at the Royal Observatory in Greenwich, London. It is the same as UTC+00:00.
- •GMT is based on the Prime Meridian (0° longitude) passing through Greenwich, London.
- •The Royal Observatory in Greenwich has been the reference point for GMT since 1884.
- •GMT and UTC are often used interchangeably, but UTC is based on atomic clocks.
- •Iceland uses GMT year-round and never observes daylight saving time.
- •The UK switches from GMT to BST (British Summer Time) in late March each year.
IRST – Iran Standard Time
UTC+03:30Iran Standard Time (IRST) is the time zone for Iran, 3 hours and 30 minutes ahead of UTC.
- •IRST is one of only a few time zones with a 30-minute offset.
- •Iran observes daylight saving time, switching to IRDT (UTC+04:30).
- •Tehran has a metropolitan population of over 16 million.
Time Conversion Guide: United Kingdom to Iran
United Kingdom runs on British Summer Time (BST) at UTC+01:00, currently observing daylight saving time. Iran runs on Iran Standard Time (IRST) at UTC+03:30. That puts United Kingdom 2 hours 30 minutes ahead of Iran — a difference of +2h 30m at the current offsets.
In practice, when it is 9:00 AM in United Kingdom it is 11:30 AM in Iran. Midnight in United Kingdom is 2:30 AM in Iran.United Kingdom observes daylight saving time while Iran does not, so the gap narrows or widens by an hour part of the year.
United Kingdom to Iran time conversion table
| United Kingdom (BST) | Iran (IRST) | Day |
|---|---|---|
| 12:00 AM | 2:30 AM | same day |
| 6:00 AM | 8:30 AM | same day |
| 7:00 AM | 9:30 AM | same day |
| 8:00 AM | 10:30 AM | same day |
| 9:00 AM | 11:30 AM | same day |
| 12:00 PM | 2:30 PM | same day |
| 3:00 PM | 5:30 PM | same day |
| 5:00 PM | 7:30 PM | same day |
| 6:00 PM | 8:30 PM | same day |
| 9:00 PM | 11:30 PM | same day |
Why people convert United Kingdom to Iran time
- Scheduling a call from United Kingdom to Iran: a 10:00 AM start in United Kingdom lands at 12:30 PM in Iran, so you can confirm the slot without doing the arithmetic yourself.
- Finding shared working hours: both United Kingdom and Iran are inside the 9-to-5 working day between 9:00 AM and 2:30 PM BST time (11:30 AM–5:00 PM IRST). That is roughly 5 hours 30 minutes of usable overlap.
- Booking travel or deliveries: tracking Iran local time against United Kingdom keeps pickup windows and arrival estimates honest across the +2h 30m offset.
- Always state the zone abbreviation, not just the hour. "3:00 PM BST" is unambiguous; "3 PM" across a +2h 30m gap is not.
- Block 9:00 AM–2:30 PM BST as the recurring meeting window if you work primarily from United Kingdom and need Iran colleagues present.
- United Kingdom: Clocks fall back on Sun, Oct 25, 2026. Re-check this page after that date because the offset changes and so does the +2h 30m gap.
About GMT (Greenwich Mean Time)
Greenwich Mean Time (GMT) is the clock time at the Royal Observatory in Greenwich, London, which sits on the Prime Meridian (0° longitude). GMT serves as the reference point from which all other time zones are calculated. The United Kingdom uses GMT during winter months and switches to British Summer Time (BST, UTC+01:00) from late March to late October. Several West African nations use GMT year-round. GMT is often used interchangeably with UTC (Coordinated Universal Time), although technically they are different – UTC is based on atomic clocks while GMT is based on Earth's rotation.
About IRST (Iran Standard Time)
Iran Standard Time (IRST) is one of the few time zones with a 30-minute offset. Iran observes daylight saving time (IRDT, UTC+04:30) from late March to late September. Tehran, the capital, is one of the largest cities in the Middle East.
Best time to call between United Kingdom and Iran
Both United Kingdom and Iran sit inside the 9 AM – 5 PM working day between 9:00 AM–2:30 PM BST, which is 11:30 AM–5:00 PM IRST. That gives roughly 5 hours and 30 minutes of shared time — the safest window for a live call or meeting.
Business hours overlap
United Kingdom and Iran share 5 hours of working-hours overlap (9:00 AM–2:30 PM BST), so scheduling a live meeting is straightforward.
United Kingdom is 2 hours 30 minutes ahead of Iran (BST UTC+01:00 → IRST UTC+03:30). The shared working window is 9:00 AM–2:30 PM BST. Remember to re-check around daylight-saving transitions.
🕐 Daylight Saving Time Info
United Kingdom
☀ Currently in DST
Standard: UTC+00:00 · DST: UTC+01:00
Clocks fall back on Sun, Oct 25, 2026
Iran
Does not observe DST
Learn More About Time
Dive deeper into the fascinating world of timekeeping, time zones, and how they shape our global society:
Frequently Asked Questions
What is the time difference between United Kingdom and Iran?
United Kingdom (BST, UTC+01:00) is 2 hours 30 minutes ahead of Iran (IRST, UTC+03:30). The gap is currently +2h 30m.
How do I convert United Kingdom time to Iran time?
Add +2h 30m to United Kingdom local time. For example, 9:00 AM in United Kingdom is 11:30 AM in Iran.
What time is it in Iran right now?
Iran uses IRST at UTC+03:30. Use the live converter at the top of this page — it updates in real time and already accounts for the +2h 30m offset from United Kingdom.
What is the best time to call Iran from United Kingdom?
Call between 9:00 AM and 2:30 PM BST — that maps to 11:30 AM–5:00 PM IRST and keeps both parties inside the working day.
Which is ahead, United Kingdom or Iran?
United Kingdom is 2 hours 30 minutes ahead of Iran. When it is 12:00 PM in United Kingdom it is 2:30 PM in Iran.
Do United Kingdom and Iran use different time zones?
United Kingdom (United Kingdom) uses BST at UTC+01:00, while Iran (Iran) uses IRST at UTC+03:30. The IANA identifiers are Europe/London and Asia/Tehran.
Does daylight saving time affect the United Kingdom–Iran difference?
Yes at the moment: United Kingdom is on daylight saving time and Iran is not, so the +2h 30m gap shifts by an hour when exactly one of them changes clocks.
Which other cities share United Kingdom's time zone?
BST also covers London, Dublin, Lisbon, Accra, Reykjavik, Edinburgh, Casablanca, Dakar and 5 more.
Which countries use BST, United Kingdom's zone?
BST is used in United Kingdom, Ireland, Iceland, Portugal (mainland), Ghana, Senegal, Mali, Mauritania and 7 more.
Is there a day difference between United Kingdom and Iran?
Not normally. The +2h 30m gap only pushes the date over for late-evening times.
What is the time difference between United Kingdom and Iran?
Iran is +2h 30m from United Kingdom.
What timezone is United Kingdom in?
United Kingdom operates on its local timezone.
What timezone is Iran in?
Iran operates on its local timezone.
Which countries use GMT (Greenwich Mean Time)?
GMT is used in United Kingdom, Ireland, Iceland, Portugal (mainland), Ghana, Senegal, and 9 more countries.
Does GMT observe daylight saving time?
Yes, GMT switches to BST during summer months.
What are some interesting facts about GMT?
GMT is based on the Prime Meridian (0° longitude) passing through Greenwich, London. The Royal Observatory in Greenwich has been the reference point for GMT since 1884.
Which cities are in the IRST timezone?
Major cities in the IRST timezone include Tehran, Isfahan, Mashhad, Tabriz, Shiraz, Karaj.
What is the UTC offset for IRST?
Iran Standard Time (IRST) is at UTC+03:30. During daylight saving time, it shifts to IRDT.
What should I know about the IRST timezone?
IRST is one of only a few time zones with a 30-minute offset. Iran observes daylight saving time, switching to IRDT (UTC+04:30).
When is it midnight in United Kingdom, what time is it in Iran?
When it is 12:00 AM (midnight) in United Kingdom (GMT), it is +2h 30m later in Iran (IRST).
Related Developer Tools
Explore more tools that work great with timezone conversions for international teams:
Related Timezone Conversions
More United Kingdom time conversions
- uk to london
- uk to gmt
- uk to bst
- uk to new york
- uk to dubai
- uk to tokyo
- uk to singapore
- uk to sydney
- uk to los angeles
- uk to paris
- uk to delhi
- uk to mumbai
- uk to berlin
- uk to hong kong
- uk to toronto
- uk to kathmandu
- new york to uk
- london to uk
- dubai to uk
- tokyo to uk
- singapore to uk
- sydney to uk
- los angeles to uk
- paris to uk
- delhi to uk
- mumbai to uk
- berlin to uk
- hong kong to uk
- toronto to uk
- kathmandu to uk
See every conversion from United Kingdom →·See every conversion from Iran →