GMT to PST Time Zone Converter
This converts London time (GMT in winter, BST in summer) to US Pacific Time — Los Angeles, San Francisco, Seattle. Pacific runs 8 hours behind London for most of the year. Both sides observe daylight saving but switch on different dates, so the gap is briefly off by an hour each spring and fall. The tool applies the right offset for your date.
Enter a date and time to convert.
Daylight saving is applied automatically for the date you pick. Labels like PST/EST name the zone (Pacific/Eastern); the real abbreviation shifts to PDT/EDT during daylight saving, and gmt here means London (GMT in winter, BST in summer) while utc stays fixed.
The time difference
US Pacific Time usually sits 8 hours behind London — subtract 8 from the London clock. Both regions observe daylight saving, so for most of the year they move together and the 8-hour gap holds. They just don't switch on the same day: the US changes a few weeks apart from the UK, so during two short windows the difference shrinks to 7 hours before returning to 8. This is the widest gap between London and the mainland US.
A worked example
Take 9:00 AM in London. On January 15, 2026 (winter), that is 1:00 AM PST in Los Angeles. On July 15, 2026 (summer), it's still 1:00 AM PDT — the usual 8-hour gap holds at both anchor dates. That's the small hours on the West Coast, and still the same calendar day.
Daylight saving & the abbreviation caveat
"GMT" here means London's clock — GMT in winter, BST in summer. "PST" is really Pacific Time all year: PST in winter, PDT (Pacific Daylight Time) in summer, and locals just say PT. The US switches on March 8 and November 1, 2026, while London switches on March 29 and October 25. Because those dates differ, the gap is briefly off by an hour in late March and late October. The converter uses the correct offset for the date you enter, so a 7-hour result during one of those windows is expected, not a glitch.
When you'll use it
Great for scheduling with tech teams in San Francisco or Seattle, timing a US product launch or Hollywood live stream, or catching a West Coast sports event. With eight hours between them, London afternoons meet Pacific mornings — often the only sensible window for a live call.
Frequently asked questions
How many hours behind London is US Pacific Time?
Eight hours for most of the year. When it's 12:00 noon in London it's 4:00 AM in Los Angeles. The gap only shifts by an hour during the short windows when the US and UK clocks are out of step.
What's the difference between PST and PDT?
PST is the winter name; from mid-March to early November the US West Coast moves to Pacific Daylight Time (PDT). Locals just call it Pacific Time, or PT, in either season.
When is the gap not exactly 8 hours?
During March 8–29 and October 25–November 1, 2026. The US and UK change clocks on different dates, so for those short stretches Pacific is 7 hours behind London instead of 8.