IRST to BST converter

Iran Time (Tehran) to UK Time (London, Dublin, Lisbon).

IRST3:37 AMSat 31 Oct 2026

→

BST12:07 AMSat 31 Oct 2026

BST is 3 h 30 min behind IRST.

Pick a time in IRST

⇄ BST to IRST

9:00 AM IRST = 5:30 AM BST same day

Best time to meet

The best time to meet is between 1:00 PM and 5:00 PM IRST, which is 9:30 AM to 1:30 PM BST. Both sides are then inside 9 AM to 5 PM.

IRST to BST time table

For 31 Oct 2026. Green rows: both sides between 9 AM and 5 PM.

IRST	BST
12:00 AM IRST	8:30 PM BST previous day
1:00 AM IRST	9:30 PM BST previous day
2:00 AM IRST	10:30 PM BST previous day
3:00 AM IRST	11:30 PM BST previous day
4:00 AM IRST	12:30 AM BST
5:00 AM IRST	1:30 AM BST
6:00 AM IRST	2:30 AM BST
7:00 AM IRST	3:30 AM BST
8:00 AM IRST	4:30 AM BST
9:00 AM IRST	5:30 AM BST
10:00 AM IRST	6:30 AM BST
11:00 AM IRST	7:30 AM BST
12:00 PM IRST	8:30 AM BST
1:00 PM IRST	9:30 AM BST
2:00 PM IRST	10:30 AM BST
3:00 PM IRST	11:30 AM BST
4:00 PM IRST	12:30 PM BST
5:00 PM IRST	1:30 PM BST
6:00 PM IRST	2:30 PM BST
7:00 PM IRST	3:30 PM BST
8:00 PM IRST	4:30 PM BST
9:00 PM IRST	5:30 PM BST
10:00 PM IRST	6:30 PM BST
11:00 PM IRST	7:30 PM BST

Quick answers

9:00 AM IRST = 5:30 AM BST
12:00 PM IRST = 8:30 AM BST
3:00 PM IRST = 11:30 AM BST
5:00 PM IRST = 1:30 PM BST
9:00 AM BST = 12:30 PM IRST
12:00 PM BST = 3:30 PM IRST
5:00 PM BST = 8:30 PM IRST

Does the gap change during the year?

Yes, because of daylight saving. Until 28 Mar 2027: BST is 3 h 30 min behind IRST. From 28 Mar 2027 to 31 Oct 2027: BST is 2 h 30 min behind IRST. From 31 Oct 2027 to 26 Mar 2028: BST is 3 h 30 min behind IRST.

IRST does not change its clocks. BST next changes its clocks on 28 Mar 2027 (forward 1 h, to UTC+1), then on 31 Oct 2027 (back 1 h, to UTC+0).

About IRST and BST

IRST here means Iran Time, the clock in Tehran. Right now it is UTC+3:30. It has no daylight saving.

BST here means UK Time, the clock in London, Dublin, Lisbon. Right now it is UTC+0. In winter the same clock is called GMT. This page follows the real clock all year.

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