Many people have asked about the best way to get from Whistler through the border to the USA.  There are basically four route options for driving between Metro Vancouver and the U.S.A.

One is to follow Hwy 99 right through Vancouver to Douglas B.C. more commonly known as the Peace Arch Crossing near Blaine, WA to Interstate 5 in Washington State. 

The second is to follow Hwy 1 east to 176th St (Exit 53) in Surrey which is Hwy 15 (Pacific Highway) to the Pacific Highway Crossing commonly known as the Truck Crossing. The highway continues as U.S. Hwy 543 and on to Interstate 5.

The third is to follow Hwy 1 farther east to 264th St and turn south on Hwy 13 (Exit 73) (Aldergrove-Bellingham Hwy) to the Aldergrove Crossing, called the Lynden Crossing in the U.S., where the U.S. highway 539 is called Guide Meridian Road and eventually joins Interstate 5 at Bellingham.  You should note The Aldergrove-Lynden crossing is open from 8AM - 12Midnight.  

The fourth option is to follow Hwy 1 even farther east to Sumas Road at Abbotsford and turn south on Hwy 11 (Exit 92) to the Huntingdon-Sumas border crossing which becomes US Hwy 9, then 544, then 539 to join I-5 near Bellis Fair just north of Bellingham.

The latter three look farther, but traffic tends to move along most of the day. Peace Arch can be backed up with traffic for several hours.  On weekends and in the summer when people are travelling, the easterly three crossings have an advantage.

Between Bellingham and Whistler, the Peace Arch route comes in at 2.5 hours, 207 km. The Pac Hwy one comes in at 2.5 hours, 205 km. The Aldergrove route comes in at ~3 hours, 213 km.  The Sumas/Huntingdon comes in at ~3 hours, 235km, all according to Google maps. Plus any border wait or traffic congestion anywhere. If Peace Arch has a 3 hour wait at the border the other three routes have an advantage. They don't get the same waits.

If you use the border more frequently and you are a resident of Canada or the US, applying for a NEXUS card (US/CDN $ 50 for five years) enables you to cross the border in much less time.  For example - a holiday weekend wait at Peace Arch could be between 2 or 3 hours while the NEXUS lane(s) it is unlikely you will wait more than 30-45 minutes.   NEXUS lanes are available for all the border crossings going into Canada with the exception of Lynden - Aldgergrove.  NEXUS lanes are available for travel into the US. 

See a full article on Nexus here.

For more information about the NEXUS program:

Canada Border Services Agency 

 Radio stations AM 730 and AM News1130 broadcast traffic, border and bridges, congestion and weather.

For more information for crossing the border:

EZborder crossing

The following border web cams, during daylight hours here, show what live traffic conditions are like at the three crossings.

http://www.borderlineups.com/cam.php?...

http://www.th.gov.bc.ca/ATIS/

 A good border app showing wait times is "Border Check".

For border wait times:

CBSA - U.S to Canada border wait times (Northbound to Canada)

US CBP Border Wait Times (Southbound to the US)