What is Extended Rear Facing?

Extended Rear Facing (ERF) refers to keeping children in a rear-facing car seat beyond the legal minimum requirement, typically up to 125cm or 36kg, depending on the seat’s limit. In the UK, the law requires babies to be rear-facing until at least 15 months old under R129 regulations. However, safety experts, including the NHS and British Medical Journal, strongly recommend keeping children rear-facing for as long as possible, ideally to at least age 4-6+.

Why rear-facing matters

Rear-facing seats protect a child’s most vulnerable areas: the head, neck, and spine. In a forward-facing seat, a child’s body is held in place by the harness or seatbelt, but their head is thrown forward with great force during a crash - especially in a frontal collision, which accounts for 72% of serious accidents.

In contrast, a rear-facing seat spreads the crash forces evenly across the child’s back and head, acting as a cradle. This drastically reduces the pressure on the neck. In fact, crash testing shows that forward-facing seats can expose a child’s neck to up to 300kg of force, compared to just 60kg when rear-facing.

The science behind ERF

Young children are not just small adults. Their spines are made largely of soft cartilage, which undergoes a process called ossification, gradually turning to bone, over many years. This isn’t fully complete until late adolescence. Before this, a child’s spinal column can stretch up to 2 inches, but even ¼ inch of stretch can cause catastrophic damage to the spinal cord.

Children also have larger heads in proportion to their bodies, about 25% of their body weight at birth, compared to just 6% in adults. This top-heavy anatomy puts enormous strain on the neck in a crash.

Myths vs. facts

It’s a common misconception that children will be uncomfortable or break their legs if kept rear-facing for longer. In reality, there are no recorded cases of leg breaks from rear-facing crashes, while forward-facing injuries to the legs and spine are far more common. Children are also naturally flexible and often prefer to sit cross-legged.

Global evidence

Countries like Sweden, where children routinely rear-face until 4-6 years old, have some of the lowest child road death rates in the world. Studies show that rear-facing reduces the risk of serious injury in a crash by 92% (European Transport Safety Council, 2018) and children under 2 are 75% less likely to die or be seriously injured when rear-facing (American Academy of Pediatrics, 2011).

FAQ

“My car seat says it’s suitable from 0-4 years, so that will be fine, right?”

Not necessarily. The age range on a car seat is just a rough guide. What really matters is your child’s height and weight - not their age. Many 4-year-olds haven’t finished ossifying (hardening) their bones and still benefit hugely from rear-facing. If your seat only rear-faces to 18kg or 105cm, your child may reach that limit well before age 4, especially if they’re on a higher centile. Look for a seat that allows rear-facing up to 125cm or 36kg for maximum protection.

“But they’re getting too big and their legs are bent!”

That’s totally normal-and not a safety concern. Children are flexible and often prefer to sit with bent or crossed legs.

Leg discomfort is not dangerous, but spinal injury from forward-facing too soon can be. There’s no evidence that children are at greater risk of leg injuries in rear-facing seats, in fact, the opposite is true.

“Won’t they be uncomfortable rear-facing at that age?”

Many children are happier rear-facing because they’re well supported, can nap comfortably, and see more through side and rear windows as ERF seats typically sit higher up in the vehicle. If your seat is correctly installed and well-fitted, most children remain content well into toddlerhood and beyond.