Time Zone Converter

The UK uses Greenwich Mean Time (GMT, UTC+0) in winter and British Summer Time (BST, UTC+1) from the last Sunday in March to the last Sunday in October. This calculator automatically accounts for the current DST status when converting between UK time and other zones.

Many countries change their clocks on different dates or do not observe daylight saving at all. The calculator uses the IANA time zone database to handle these differences accurately. It shows you the current time in both locations and highlights any date-line crossings.

For business scheduling, the tool can show overlapping working hours between two time zones — useful for arranging calls with colleagues or clients in different regions without anyone having to work unsociable hours.

UK timezone — GMT vs BST. UK uses GMT (UTC+0) in winter, BST (UTC+1) in summer. Clocks forward 1 hour on last Sunday March at 1am; back on last Sunday October at 2am. 2026 dates: BST starts 29 March 2026; ends 25 October 2026. Term: Daylight Saving Time = BST in UK; never Eastern/Pacific (US terms). Northern Ireland same as rest of UK. Republic of Ireland: Irish Summer Time = BST equivalent.

Business timezone offsets from UK. From UK winter (GMT): New York UTC−5; LA UTC−8; Dubai UTC+4; Mumbai UTC+5:30; Singapore/HK UTC+8; Tokyo UTC+9; Sydney UTC+10 (or UTC+11 Australia summer). Summer (BST): UK shifts +1 — but other zones may also DST-shift. Best trading overlap: London/NY 13:00-16:30 UK time (most liquid forex hours); London/Asia 08:00-09:00 UK morning. Stock exchange overlap windows have ripple effects on volatility.

UK-Australia time gap — extreme working hours. Sydney 9-11 hours ahead of UK (varies with both countries' DST). Maximum gap: November to April when UK on GMT, Australia on AEDT. 'Same workday' overlap UK 6-9am = Sydney 5-8pm: small window for meetings. Most UK/Aus business async via Slack/email. Timezone abbreviations: AEST UTC+10, AEDT UTC+11, JST UTC+9, IST UTC+5:30, EST UTC−5.

Future of UK DST. EU voted 2019 to abolish DST changes from 2021 — implementation delayed indefinitely (no consensus on which time to keep). UK left EU 2020 — independent decision. UK government 2023 consultation: 64% prefer keeping DST changes. Northern Ireland complication: keeping DST while Ireland abolishes would create border issue. UK clocks will continue to change in 2026 and beyond — no Parliament bill on table.

Time zone trivia. Greenwich Meridian (0° longitude) defined at Royal Observatory Greenwich 1884. Russia: 11 time zones (largest country). China: 1 official time zone (Beijing time) despite 5,000km width. India: UTC+5:30 (half-hour offset). Nepal: UTC+5:45 (quarter-hour offset). Antarctica: many bases use New Zealand or Chile time. Dateline: UTC+12 vs UTC−12 (1 day apart — Pacific islands east of dateline are 'tomorrow' compared to islands west).