Kathmandu Time Zone: Nepal Time (NPT) and the Unusual UTC+5:45
Kathmandu runs on Nepal Time (NPT) at UTC+5:45 — five hours and forty-five minutes ahead of Coordinated Universal Time. The IANA timezone identifier is Asia/Kathmandu, covering the whole of Nepal. NPT is genuinely rare: it is one of only three time zones in the world that use a 45-minute offset, alongside the Chatham Islands of New Zealand (UTC+12:45) and the small Eucla region of Australia (UTC+8:45). Every other country on Earth settles for whole-hour or half-hour offsets.
Why is Nepal UTC+5:45? The offset is anchored to solar time. Nepal aligned its clocks to the mean solar time of the 86°15′E meridian, which passes near Gauri Shankar mountain east of Kathmandu — and 86.25 degrees of longitude converts to exactly 5 hours 45 minutes ahead of Greenwich. The choice keeps clock time very close to the actual position of the sun over the Kathmandu Valley (at 85.32°E, the capital's solar time is only a few minutes off). Just as importantly, it stakes out a distinct national identity between two giant neighbours: 15 minutes ahead of India's UTC+5:30 and 2 hours 15 minutes behind China's UTC+8. A sovereign time zone, even one just a quarter-hour apart from India's, is a statement of independence that Nepal has maintained ever since adopting the offset.
Nepal does not observe daylight saving time. NPT stays at UTC+5:45 every day of the year. Combined with the unusual base offset, that produces time differences that never land on round numbers: Kathmandu is 5 hours 45 minutes ahead of London in winter (GMT) and 4 hours 45 minutes ahead during British Summer Time; 10 hours 45 minutes ahead of New York during EST and 9 hours 45 minutes during EDT; and always exactly 15 minutes ahead of Delhi, Mumbai and Kolkata.
The quarter-hour offset has real consequences for scheduling. Calendar tools handle Asia/Kathmandu correctly, but humans often don't: a "9 o'clock" call arranged loosely with a partner in India or Bangladesh can silently drift by 15 or 45 minutes if someone rounds the offset. The safest habit when working with Kathmandu is to state the city explicitly in invitations and let the software convert, rather than adding offsets in your head. Trekkers and travellers notice it too — flights from Delhi land in Kathmandu at times that look oddly misaligned until you remember the 15-minute shift, and Bangladesh next door sits another 15 minutes ahead of Nepal at UTC+6.
Kathmandu sits at about 27.72°N, 85.32°E in a Himalayan valley at roughly 1,400 metres. One more scheduling quirk worth knowing: the Nepali weekend is Saturday — offices and government work Sunday through Friday — so a Friday deadline in New York or London corresponds to an ordinary working day in Kathmandu, while Saturday emails will wait until Sunday morning, Nepal time.