The Sienna’s Back Seat Is Still Failing Its Hardest Test

A Marginal IIHS score for back-seat protection keeps the 2026 Toyota Sienna off the institute’s award list despite Good ratings almost everywhere else.

The trouble in the updated moderate overlap test is all in the second row. The Sienna’s structure and its driver protection rated well. Its rear passenger’s restraints and dummy kinematics rated Poor, however, and the rear passenger’s chest measure rated Acceptable. Both IIHS awards require a Good rating in that test, and the Sienna’s other scores would otherwise be good enough for a Top Safety Pick.

The IIHS ratings come from a test of a 2023 Sienna LE and apply to 2023 through 2026 models. The rest of the scorecard is solid, with Good ratings in the small overlap front test on both sides, the updated side test, headlights on every trim, seat belt reminders and LATCH ease of use, plus an Acceptable rating for pedestrian front crash prevention.

Test	Rating
Small overlap front	Good
Moderate overlap front (updated)	Marginal
Rear passenger restraints and kinematics	Poor
Side (updated)	Good
Headlights	Good
Pedestrian front crash prevention	Acceptable

The result dates back to the IIHS’s first round of minivan tests under the tougher rear-seat criteria in September 2023. The Sienna was equipped with rear belt pretensioners and force limiters, which are meant to manage belt forces, but the rear dummy still submarined beneath the lap belt. That raises the risk of abdominal injuries, and the shoulder belt also slid off the shoulder toward the dummy’s neck. "That’s concerning because those injuries can be life-threatening," said Jessica Jermakian, IIHS vice president of vehicle research, at the time.

Its rivals do no better, as the IIHS’s current minivan class ratings list the Chrysler Pacifica and Kia Carnival as Marginal in the updated moderate overlap test and the Honda Odyssey as Poor, so no minivan currently qualifies for either award.

The Toyota Report Take

Matching the Pacifica and Carnival isn’t much comfort, because the second row is where minivan buyers put their kids. Toyota gave the Sienna the right hardware in the form of pretensioners and force limiters, so the remaining fix is whatever lets the dummy slide under the lap belt, whether that is the belt anchors or the seat cushion. This rating has stood for four model years now, and Toyota should make the Sienna the first minivan to earn a Good score in this test before the next one rolls around.