I just went to the police department to have my car seats checked and asked the same question. They said it was not a matter of height, it was more about weight. Her recommendation was to keep them rear facing until at least 30 lbs. She said that 33lbs was the best, but if I could get to 30 that would be great.

Hope that helps!

I've heard that it's 1 year old and 20 lbs.  Regarding the previous poster's 30lbs note, I think it might depend on the child as to how feasible this is.  My son is still only 25 lbs approaching 2yrs old but he is so long that rear-facing has his legs all squished up so we turned him forward.

Legally the previous poster is correct - California law states that a child must be in a rear facing car seat until the age on one and the child has reached either 20 or 21lbs (I can't remeber which).  As with all laws like this you cannot take this as 'when these requirements are reached it is suddenly safe to turn your child around' where it wasn't the day before!  The way I see it is that this is the absolute earliest that you should do it, but I intend to keep my son rear facing as long as possible.  The logistics of this are never-the-less hard as most carrier style infant car seats only carry infants up to 21lbs (actually height is a bigger factor for out growing these seats) so usually you must buy a convertable car seat to cover the interim.  As to when it is safe to turn around - the 30/33lb answer seems to make the most sense but if you have a child screaming blue murder in the back because the car seat is uncomfortable or he just wants to see Mommy then that is hardly safe either.  No good answer I'm afraid but that is my two-pennys worth!

The laws have said (for many years) that they must be at least one year of age and 35 lbs.  This means they must meet both requirements to be turned around.  The one year ensures that their spinal cord and neck can sustain a blow/whiplash in a crash when forward facing, and the 35 lbs ensures that they are large enough to not be thrown around dangerously.  My daughter is only 23 lbs at 16 months and she is still rear facing even though her legs are getting a little long- it has nothing to do w/ has short or tall they are!  Also, make sure that if your daughter meets both these requirements u have the proper type of car seat- some rear facing cannot be turned forward, and not all have the same weight limits!  Trust me there's NO way the law says 20 lbs- that is the limit most INFANT seats have to stop being used; if this was the limit you'd never have a rear facing toddler seat, you'd just have to go straight to forward facing.  Plus, I worked in law enforcement for years, if u want to be absolutely sure, go to your police or fire station, or even the transportation offices have people trained to check your seat for you.

"The laws have said (for many years) that they must be at least one year of age and 35 lbs"

Sorry - that is not true.  Most state laws allow for children to be forward facing at age 1 and 20 lbs.  There are many resources available on the topic online - http://www.statehighwaysafety.org/html/stateinfo/laws/childsafety_laws.html and http://www.carseat.org/

 That said, research has shown that keeping a child rear-facing as long as possible is the safest way to go.  As someone else mentioned, having your kids legs scrunched up may not be super-comfortable, but it is still safer.  From what I've read on other list-servs, in Sweden - makers of the uber-safe Volvo :-) - many people keep kids rear facing until age 5!

Did u even bother to check MY state before u decided to quote me?  SORRY, but that IS true. I don't need to check some other internet site since I actually worked as a juvenile officer...I was stating what the ideal standard is, which is the maximum weight that states use.  So, if u want to know when the best time to do it IF you're planning on turning your kid around at the earliest time, the safest (and by law in a lot of states, hence weight limits on pumpkin seats) is 35.

 Sorry I thought we were on a San Francisco message board - I was referring to CA law!

Thanks, I will plan to keep her facing backwards as long as possible.