The five-day sale starts now and ends 8:59 p.m. (Pacific) Monday. It applies to reserved coach seats and Acela business class seats for travel between March 25 and July 29. Children ages 2 to 12 can come along for half the price of an adult fare.
There are no blackout dates either, so you can reserve a spot for Memorial Day or the Fourth of July as long as you reserve before the sale ends.
During the sale, two adults and two children could travel by train from L.A. to Portland, Ore., for $242 (adult tickets cost $121, plus free companion ticket).
Travelers can snag savings on East Coast routes, such as $96 between New York City and Washington, D.C., and $83 between Boston and New York City.
The companion fare sale applies to most routes nationwide, except the Pacific Surfliner and Capitol Corridor in California.