Convert time from IRST to BST. Enter any time to see the equivalent BST time, compare current IRST and BST times side by side, and find overlapping business hours for calls and meetings.
Use this IRST to BST converter to compare Iran and United Kingdom time, check the 2 hours and 30 minutes gap, and confirm the right slot for calls, handoffs, and deadlines. Good overlap starts around 12:00 PM IRST / 9:30 AM BST.
Converting between Iran Standard Time and British Summer Time means accounting for a 2 hours and 30 minutes gap — here's how to do it in under 10 seconds with no sign-up.
Pick the date and time in Iran Standard Time (UTC +3:30) that you want to convert. Hit "Now" to load the current irst time instantly, or use "+1h" to step forward and compare.
The equivalent British Summer Time (UTC +1) time appears immediately. Since bst is 2 hours and 30 minutes behind of irst, most daytime conversions stay on the same calendar day.
Click "Copy Time" to grab the bst result for your calendar or message. Use "+1d" to check how the conversion shifts across dates — useful when Daylight Saving Time changes the gap.
When someone in Iran suggests 12:00 PM irst, that's 9:30 AM bst. This converter shows the overlap so both sides agree on one slot — no back-and-forth.
Late-night irst times can land on a different date in bst because of the 2 hours and 30 minutes offset. The converter labels "next day" or "previous day" next to the result so you never send a message a day early or miss a deadline.
The half-hour offset between irst (UTC +3:30) and bst (UTC +1) already makes mental math tricky — add Daylight Saving Time and the gap can shift further. This converter uses live UTC offsets, so you're always accurate.
Product launches, sports matches, and webinars are often announced in irst. Convert the event time to bst so you know exactly when to tune in — with a 2 hours and 30 minutes difference, a morning event in Iran falls during work hours in United Kingdom.
Quick-reference conversion table covering every hour of the day at a glance.
Iran Standard Time to British Summer Time full day schedule
| Iran Standard Time | British Summer Time |
|---|---|
| 12:00 AM |
9:30 PM
(previous day)
|
| 1:00 AM |
10:30 PM
(previous day)
|
| 2:00 AM |
11:30 PM
(previous day)
|
| 3:00 AM |
12:30 AM
|
| 4:00 AM |
1:30 AM
|
| 5:00 AM |
2:30 AM
|
| 6:00 AM |
3:30 AM
|
| 7:00 AM |
4:30 AM
|
| 8:00 AM |
5:30 AM
|
| 9:00 AM |
6:30 AM
|
| 10:00 AM |
7:30 AM
|
| 11:00 AM |
8:30 AM
|
| 12:00 PM |
9:30 AM
|
| 1:00 PM |
10:30 AM
|
| 2:00 PM |
11:30 AM
|
| 3:00 PM |
12:30 PM
|
| 4:00 PM |
1:30 PM
|
| 5:00 PM |
2:30 PM
|
| 6:00 PM |
3:30 PM
|
| 7:00 PM |
4:30 PM
|
| 8:00 PM |
5:30 PM
|
| 9:00 PM |
6:30 PM
|
| 10:00 PM |
7:30 PM
|
| 11:00 PM |
8:30 PM
|
UK / Ireland summer offset (last Sunday of March to last Sunday of October) — UTC+1, same as CET. During BST, London aligns with continental European working hours rather than the standard 1-hour gap. Winter reverts to GMT (UTC+0).
Explore more irst conversions for major business and travel corridors. Each page includes a 24-hour chart, time difference summary, and meeting overlap guidance.
Find the time difference from any major zone into British Summer Time. Use these pages when scheduling with United Kingdom from a different region.
