San Francisco to Singapore Flights (SFO to SIN): Nonstops, Flight Time and Arrival Tips

One of the longest nonstops anywhere, on two airlines

San Francisco to Singapore is an ultra-long-haul route with nonstop service. As of recent schedules, Singapore Airlines flies it nonstop, typically with more than one departure a day, and United flies it nonstop as well. Both leave San Francisco in the late morning or evening and land in Singapore in the early morning or late evening two calendar days later, depending on the departure.

One-stop alternatives are plentiful and often significantly cheaper. The common connections are Tokyo on ANA, Japan Airlines or Singapore Airlines, Taipei on EVA Air or STARLUX, Hong Kong on Cathay Pacific, and Seoul on Korean Air. A connection adds three to six hours but breaks the journey, which some travellers prefer on a flight of this length.

Singapore is also the natural gateway to the rest of Southeast Asia. Changi has frequent connections to Bali, Bangkok, Kuala Lumpur, Phuket, Ho Chi Minh City and dozens of other cities, often within two or three hours of landing.

Flight time and distance

The great-circle distance from SFO to SIN is roughly 8,450 miles (about 13,600 km). Westbound, San Francisco to Singapore typically takes 16.5 to 17.5 hours in the air. Eastbound, Singapore to San Francisco is shorter at around 15 to 16 hours with the prevailing winds behind you.

You cross the International Date Line going west. A Monday evening departure from San Francisco lands in Singapore early on Wednesday morning, local time. Coming home, you leave Singapore in the morning or evening and arrive in San Francisco later the same calendar day. Count your hotel nights from the arrival date, not the departure date.

Leaving from SFO

Singapore Airlines and United both depart from the International Terminal's Boarding Area G, the Star Alliance side of the building. Security at Boarding Area G is busiest in the late morning and again in the evening, exactly when the Asia departures leave, so three hours ahead with checked bags is a reasonable target.

BART runs directly into the International Terminal from downtown San Francisco in around 30 minutes and from the East Bay with at most one change; from the South Bay, Caltrain to Millbrae and a BART transfer is simplest. If you are connecting from a domestic United flight in Terminal 3, you can walk airside to Boarding Area G without re-clearing security.

For a flight of this length, what you carry on matters more than usual: a refillable water bottle, layers for a cold cabin, and anything you need to sleep. Economy on both airlines has seatback entertainment, but download what you want in case the system is slow.

Arriving at Changi and getting into the city

Changi has four terminals, and the ones you use depend on the airline. Singapore Airlines uses Terminals 2 and 3; United typically uses Terminal 3. Terminals 1, 2 and 3 are linked by the free Skytrain and by walkways, and Terminal 4 by shuttle bus. Immigration uses automated lanes that most visitors can use once their arrival card is filed, and the whole process from gate to taxi queue is usually quick.

The airport is at the eastern tip of the island, about 20 km from the centre. Getting in:

• MRT: the Changi Airport station is between Terminals 2 and 3, and the East-West Line reaches the city centre in 30 to 40 minutes with one change at Tanah Merah. Use a contactless bank card or buy a stored-value card at the station.
• Taxi or ride-hailing: 20 to 30 minutes to the city centre outside rush hour, with surcharges at night and in peak periods. Taxi queues move quickly and ride-hailing pickups are from signed points at each terminal.
• Airport shuttle: shared vans to city hotels, useful if you are travelling with heavy bags and arrive early in the morning.

Jewel, the garden and shopping complex attached to Terminal 1, is worth an hour if you have a long layover or arrive early for your flight home.

Entry requirements, the arrival card and local rules

As of recent rules, US passport holders can visit Singapore for short stays without a visa, but everyone must submit the SG Arrival Card online within the three days before arrival. It is free on the Immigration and Checkpoints Authority website and app, and you cannot use the automated immigration lanes without it. Your passport should be valid for at least six months. Check the ICA website for the current rules.

Singapore enforces some laws that surprise visitors. Chewing gum is restricted, vaping devices and e-cigarettes are banned and confiscated on arrival, and penalties for drugs are severe. Medications that are controlled in Singapore, including some common prescription drugs, may need prior approval, so check the Health Sciences Authority guidance for anything you take regularly.

When to fly and when to book

Singapore sits almost on the equator, so the temperature barely changes through the year: hot and humid every day. The northeast monsoon from November to January brings more rain and slightly cooler afternoons; the period from February to April is usually the driest. Flights are not disrupted by weather in the way they are in Tokyo or Hong Kong.

Demand, not weather, drives fares. Chinese New Year in late January or February, the Formula One night race in September or October, the June school holidays and the US summer and Christmas periods all push prices up from San Francisco. Hotel rates in the city spike sharply during the race weekend and major conferences even when flights do not.

The quietest periods are usually late February through April outside Easter, and late October through early December. Book three to five months ahead for peak dates; for the rest of the year, six to ten weeks ahead usually shows the full range of nonstop and one-stop fares.

Time difference and jet lag

Singapore is 15 hours ahead of San Francisco during Pacific Daylight Time and 16 hours ahead in winter, because Singapore does not observe daylight saving. Day and night are nearly reversed. Westbound arrivals in the early morning are the hardest: you have a full day ahead after a short night. Get outside, eat at local mealtimes and resist a nap longer than half an hour. Eastbound you land in San Francisco in the morning or afternoon and most people need three or four days to feel normal.

What travellers on this route get wrong

The most common mistake is miscounting the hotel nights across the date line and arriving a day later than the booking. The second is forgetting the SG Arrival Card and filing it in the immigration queue on a phone with no signal. The third is packing a vape, which is confiscated at the border with a fine. The fourth is underestimating the humidity and planning a full day of walking at midday; locals move between air-conditioned spaces for good reason.