How do I know my car seat is fitted correctly?

The ISOFIX checklist

• Both connector indicators green — half-clicked connectors show red or half-red on every major brand.
• Support leg firm to the floor, indicator green, and not resting on an underfloor storage lid (check your car's handbook — some need a floor insert).
• Or top tether tight to the marked anchor point, not to a luggage hook.
• Seat checked against the compatibility list for your exact car — ISOFIX standardises the connection, not the fit.

The belt-fit checklist

Follow the routing diagram exactly (blue guides for rear-facing, red for forward), then push your full body weight into the seat while pulling the belt tight. Test at the belt path: the seat shouldn't move more than about 2–3cm side to side or forward.

The harness, every single trip

Height at or just below the shoulders rear-facing (at or just above, forward-facing). Pinch test: with the harness done up, you shouldn't be able to pinch a horizontal fold of strap at the collarbone. Thick coats off before strapping in — compression in a crash turns a snug harness into a loose one.

Free expert checks

Many nursery retailers, some fire services and local road safety teams run free fitting checks — one appointment catches the errors you can't see yourself. Our car seat guide covers choosing the right R129 seat in the first place.