At what age is it okay to take your child out of the car seat and put them in a booster seat?

Why does it matter how big and heavy the car seat is? Install it and leave it there. If you have more than one car then buy a second seat. You can get a convertible from Cosco for under $50. Boosters are for age 4+. The longer your kid is in a 5 point harness the safer they will be. Plus, your son is only 31 lbs. I wouldn't even think of moving him to a booster till he is 40+ lbs. Ideally 50+ lbs.

Minimum of age 4 and 40 pounds under the law in most states. A car seat is much safer even when he is over 4 if he still is within the weight and height requirements.

Check the laws in your state or province. Where I am, they absolutely must be in a 5-point harness car seat until they have reached 40lbs. 40lbs is the law for many states, although many still recommend keeping them in as long as you can. You need to look up the specific requirements for your area (for example NY says must be 40lbs to be in a booster seat as well). Some states do make the age of 4 also a requirement, but most seem to have it limited based on weight - and your son is no where near the 40lbs he needs to be to be safe in just a booster seat. You shouldn't be moving the car seat regularly. Install it in one car and leave it. The more you move it the more likely you are to make a mistake and not have it installed correctly. If you have multiple cars, buy multiple car seats and don't move either. The weight of the seat should never be a factor.

Not until my son turned 4. You should really go by the weight that is recommended for the booster seat.

If he fits in his car seat, leave him there. For his weight and age, for the safest you really need to look into a high-weight harnessed booster (with top slots of over 17 inches). The next step is a high-back booster, not too good for a lil one htis age but not bulky. If you go budget, DO NOT buy a backless booster, these offer no side impact protection. I have know two kids killed in car accidents while seated in a backless booster, both kids were about 40 pounds in weight. I have mine in a Evenflo Meastro harnessed booster, he is 5 years old but weighs only 35 pounds. It seems though you don't want any car seat but the minimum, and with the minimum you get the minimum level of safety at this age.

When they outgrow it. Most toddler seats hold until around age 3 or 4 but that's going by average weight and height. If he still fits, keep him in it. If not either make the switch or get a toddler seat that holds a bigger child. (Not saying your child is fat, every child is different in height and weight)

No, not if you can safely keep your child in a harnessed seat for a while longer. Most 3-year-olds are not ready to ride in a booster seat in the car. I suggest that you keep your baby in a harnessed car seat to at least 40 pounds and 4 years, but preferably longer. Booster car seats can be used up to 40 to 53 inches or 40 to 80 pounds, depending on the seat.

There really is no magic age, it depends on how big your son is. Most booster seats are for children over 40 pounds. Your car seat should say on the side tag what the weight restrictions for the 5 point harness is. Once he is too big for that 5 point harness (usually 40 lbs.) he can be moved to a booster seat.

id say when he turns 4