What is the Swedish Plus Test?

The Swedish Plus Test is conducted by Swedish widely recognised as the most rigorous crash test in the world for child car seats - and the only one that specifically measures the forces exerted on a child’s neck during a collision.

It goes far beyond the legal requirements of R44 or R129, and only a small number of rear-facing seats have ever passed it.

What makes it different?

Most car seat regulations focus on general crash protection, including head movement and chest forces during frontal or side impacts. The Swedish Plus Test includes all that - and adds a layer of intensity no other test does:

• It uses a higher speed (34.8mph / 56 kmh) than R44 or R129 and, crucially, is conducted with a very short braking distance into a solid barrier, creating much more extreme crash forces.

• It directly measures neck forces using sensors to ensure they remain below a strict safety threshold.

• As a result, no forward-facing seat has ever passed, and only rear-facing toddler seats are eligible.

Why does this matter?

Children’s necks are especially vulnerable: their relatively large heads and developing spine can’t absorb crash forces like an adult’s. By measuring and limiting neck loads, the Plus Test addresses the primary risk in frontal collisions - something R44 and R129 don’t directly measure.

This focus on neck safety and high-energy testing makes it the gold standard of car seat performance.

What does it mean if a seat is Plus Tested?

If a seat has passed the Swedish Plus Test, it offers a level of protection that exceeds standard legal requirements. It’s a pass/fail test - there are no scores - so any seat that passes can keep neck forces within safe, survivable limits.

Most of these seats are belt-installed rear-facing models, often offering long-term rear-facing up to 36kg and 125 cm.

FAQ

Is the Plus Test mandatory?

No - it’s entirely voluntary. Manufacturers choose to submit their seats, and only a few meet the strict criteria.

Why don’t infant carriers or boosters go through the Plus Test?

The test focuses on neck forces in high-energy frontal impacts, relevant for toddlers transitioning out of infant carriers. Infant carriers are already rear-facing, and high‑back boosters are used with the vehicle seatbelt and are designed for use after the most vulnerable developmental stages.

Does my child need a Plus Tested seat?

Not necessarily - many R129 seats from trusted brands offer strong protection. But if maximum neck safety and protection in the most severe crashes are priorities, a Plus Tested seat offers reassurance beyond legal minimums.