Standard year-round offset: London is 8 hours ahead of Seattle in both winter (PST UTC-8 → GMT UTC+0) and summer (PDT UTC-7 → BST UTC+1). When it is 9:00 AM in Seattle, it is 5:00 PM GMT/BST in London. Best meeting window: 8:30 AM – 11:30 AM PST/PDT in Seattle (4:30 PM – 7:30 PM GMT/BST in London — Morning/Evening Shoulder Bridge).
The standard baseline difference between Seattle (United States) and London (United Kingdom) is 8 hours (London ahead of Seattle) in both winter (PST UTC-8 vs. GMT UTC+0) and summer (PDT UTC-7 vs. BST UTC+1). Because United States and United Kingdom change Daylight Saving clocks on different Sundays, the offset temporarily shifts to 7 hours during a 14-day spring gap (Mar 14, 2027 – Mar 28, 2027) and 2-day autumn gap (Oct 31, 2027 – Nov 2, 2027).
| Date Window | Duration | Active Zones | Time Difference | Regime |
|---|---|---|---|---|
| Since Nov 1, 2026 | 133 days | PST (UTC-8) → GMT (UTC+0) | 8 hours | Standard Alignment (Active Now) |
| Mar 14, 2027 – Mar 28, 2027 | 14 days | PDT (UTC-7) → GMT (UTC+0) | 7 hours | ⚠️ DST Desync Window |
| Mar 28, 2027 – Oct 31, 2027 | 217 days | PDT (UTC-7) → BST (UTC+1) | 8 hours | Standard Alignment |
| Oct 31, 2027 – Nov 2, 2027 | 2 days | PDT (UTC-7) → GMT (UTC+0) | 7 hours | ⚠️ DST Desync Window |
At the 8 hours offset between Seattle (PST/PDT) and London (GMT/BST), there are 0 hours of simultaneous 9:00 AM – 5:00 PM working overlap. Live calls use morning and early-evening shoulder hours (ending strictly by 9:00 PM local time).
Connects Seattle (PST/PDT) and London (GMT/BST) during waking shoulder hours, finishing by 9:00 PM local time.
Covers 18 hours/day when either Seattle (PST/PDT) or London (GMT/BST) is outside 7:00 AM – 9:00 PM local time.
Because London is 8 hours ahead of Seattle, London crosses midnight into the next calendar day (+1 day) at 4:00 PM PST/PDT in Seattle. From 12:00 AM to 4:00 PM PST/PDT in Seattle, both locations are on the same weekday; from 4:00 PM PST/PDT to 11:59 PM in Seattle, Mon–Fri in Seattle maps to Tue–Sat in London.
Weekend & Workday Alignment: Friday afternoon/evening in Seattle (any slot at or after 4:00 PM PST/PDT) lands on Saturday morning/afternoon in London—which is London's weekend (Sat–Sun). Conversely, Monday morning in London (before 8:00 AM GMT) is still Sunday in Seattle (Seattle's Sat–Sun weekend). For late-day Seattle / morning London syncs, book Monday–Thursday in Seattle (Tuesday–Friday in London).
Geographically, Seattle (United States, 47.61°N, 122.33°W, IATA: SEA) and London (United Kingdom, 51.51°N, 0.13°W, IATA: LHR/LGW/STN) are separated by a great-circle distance of 7,700 km (4,785 miles, approximately 9.5h non-stop flight). By longitude, true solar time in London is 8 hours and 9 minutes ahead of Seattle (a 9-minute divergence from the 8 hours standard civil clock offset): Seattle (47.61°N, 122.33°W) sits 2.33° west of the 120.0°W PST reference meridian, so mean solar noon occurs at 12:09 PM PST in winter and 1:09 PM PDT in summer, while London (51.51°N, 0.13°W) sits 0.13° west of the 0.0°E GMT reference meridian, so mean solar noon occurs at 12:01 PM GMT in winter and 1:01 PM BST in summer.
For Seattle → London: Literal BST (British Summer Time) is UTC+1, active in the UK from the last Sunday of March to the last Sunday of October. In winter, the UK returns to GMT (UTC+0).
| Abbreviation Meaning | UTC Offset | IANA Zone | Major Cities & Regions |
|---|---|---|---|
| British Summer Time Primary Here | UTC+1 (late March – late October) | Europe/London | Active on Seattle → London: London, Manchester, Edinburgh, Belfast |
| Bangladesh Standard Time | UTC+6 (year-round) | Asia/Dhaka | Not used for Seattle → London: Dhaka, Chittagong (Bangladesh) |
| Seattle Time | London (Standard (PST/PDT → GMT/BST)) | Day Shift | Call Status |
|---|---|---|---|
| 9:00 AM PST/PDT (Morning Start) | 5:00 PM GMT/BST | Same day | Shoulder Hours |
| 12:00 PM PST/PDT (Midday / Noon) | 8:00 PM GMT/BST | Same day | Shoulder Hours |
| 3:00 PM PST/PDT (Afternoon) | 11:00 PM GMT/BST | Same day | Late evening / night |
| 6:00 PM PST/PDT (Evening Wrap-up) | 2:00 AM GMT/BST (+1 day) | +1 day | Overnight / Rest |
| Seattle (PST) | London (Standard (PST/PDT → GMT/BST)) | Day (London) | Availability (Seattle ↔ London) |
|---|---|---|---|
| 12:00 AM PST/PDT in Seattle | 8:00 AM GMT/BST in London | Same day | Seattle–London Overnight |
| 1:00 AM PST/PDT in Seattle | 9:00 AM GMT/BST in London | Same day | Seattle–London Overnight |
| 2:00 AM PST/PDT in Seattle | 10:00 AM GMT/BST in London | Same day | Seattle–London Overnight |
| 3:00 AM PST/PDT in Seattle | 11:00 AM GMT/BST in London | Same day | Seattle–London Overnight |
| 4:00 AM PST/PDT in Seattle | 12:00 PM GMT/BST in London | Same day | Seattle–London Overnight |
| 5:00 AM PST/PDT in Seattle | 1:00 PM GMT/BST in London | Same day | Seattle–London Overnight |
| 6:00 AM PST/PDT in Seattle | 2:00 PM GMT/BST in London | Same day | Seattle–London Overnight |
| 7:00 AM PST/PDT in Seattle | 3:00 PM GMT/BST in London | Same day | Seattle–London Shoulder |
| 8:00 AM PST/PDT in Seattle | 4:00 PM GMT/BST in London | Same day | Seattle–London Shoulder |
| 9:00 AM PST/PDT in Seattle | 5:00 PM GMT/BST in London | Same day | Seattle–London Shoulder |
| 10:00 AM PST/PDT in Seattle | 6:00 PM GMT/BST in London | Same day | Seattle–London Shoulder |
| 11:00 AM PST/PDT in Seattle | 7:00 PM GMT/BST in London | Same day | Seattle–London Shoulder |
| 12:00 PM PST/PDT in Seattle | 8:00 PM GMT/BST in London | Same day | Seattle–London Shoulder |
| 1:00 PM PST/PDT in Seattle | 9:00 PM GMT/BST in London | Same day | Seattle–London Late evening / night |
| 2:00 PM PST/PDT in Seattle | 10:00 PM GMT/BST in London | Same day | Seattle–London Late evening / night |
| 3:00 PM PST/PDT in Seattle | 11:00 PM GMT/BST in London | Same day | Seattle–London Late evening / night |
| 4:00 PM PST/PDT in Seattle | 12:00 AM GMT/BST in London | +1 day | Seattle–London Overnight |
| 5:00 PM PST/PDT in Seattle | 1:00 AM GMT/BST in London | +1 day | Seattle–London Overnight |
| 6:00 PM PST/PDT in Seattle | 2:00 AM GMT/BST in London | +1 day | Seattle–London Overnight |
| 7:00 PM PST/PDT in Seattle | 3:00 AM GMT/BST in London | +1 day | Seattle–London Overnight |
| 8:00 PM PST/PDT in Seattle | 4:00 AM GMT/BST in London | +1 day | Seattle–London Overnight |
| 9:00 PM PST/PDT in Seattle | 5:00 AM GMT/BST in London | +1 day | Seattle–London Overnight |
| 10:00 PM PST/PDT in Seattle | 6:00 AM GMT/BST in London | +1 day | Seattle–London Overnight |
| 11:00 PM PST/PDT in Seattle | 7:00 AM GMT/BST in London | +1 day | Seattle–London Late evening / night |
The standard time difference is 8 hours (London ahead of Seattle) in both winter (PST → GMT) and summer (PDT → BST). It temporarily shifts to 7 hours during the 14-day spring gap (Mar 14, 2027 – Mar 28, 2027) and 2-day autumn gap (Oct 31, 2027 – Nov 2, 2027).
No — at 4:00 PM PST/PDT in Seattle, it is 12:00 AM GMT/BST (+1 day) in London, which is after the 9:00 PM evening cutoff. Schedule earlier during 8:30 AM – 11:30 AM PST/PDT (4:30 PM – 7:30 PM GMT/BST in London).
Aim for 8:30 AM – 11:30 AM PST/PDT in Seattle, which is 4:30 PM – 7:30 PM GMT/BST in London (0h/day of 9–5 overlap). Avoid calling between 1:00 PM – 7:00 AM PST/PDT (+1 day) in Seattle (9:00 PM – 3:00 PM GMT/BST (+1 day) in London), when at least one city is outside 7:00 AM – 9:00 PM.
Seattle: Sun, Mar 14, 2027 (PST → PDT, new gap: 7 hours (PDT UTC-7 vs GMT UTC+0)). London: Sun, Mar 28, 2027 (GMT → BST, new gap: 8 hours (BST UTC+1 vs PDT UTC-7)).
Year-round under standard alignment, 9:00 AM in Seattle is 5:00 PM GMT/BST in London, and 12:00 PM (noon) in Seattle is 8:00 PM GMT/BST in London.