what age for booster seats

In Australia, kids typically move to a booster seat from about age 4 and must use one until they’re under 7 (or a forward‑facing seat with an inbuilt harness).

After 7, keep them in a booster until an adult belt fits properly—the “five‑step test” or roughly 145 cm tall is the usual yardstick.

Lap‑sash across the shoulder, not the neck; no puffy jackets; and secure it like your pride and joy depends on it—because it does.

Rules vary slightly by state and territory, so check local road laws and AS/NZS 1754 guidance if you want the chapter and verse.