What's the difference between size 24 months and 2T?

24m and 2T are both made for diaper wearers. 4T is made for diapers, 4 is not. But with disposable diapers being so thin it doesn't make much difference really.

The difference is whether it is part of their infant line, or toddler line.

For instance something that is 24m will also be available in 18m, 12m etc. Something in 2T will likely also be made in 3T and 4T.

Therefore, 24m is more likely to have "baby" characters on it, and 2T is more likely to have "big boy / big girl" characters on it. The general make of a 24m is going to be targeted more for babies, since it is part of the baby line. Onsies and footed sleepers made for 2 year olds are more often going to be called 24m then 2T, because more babies wear those then toddlers. Therefore the design team in charge of infant apparel makes them, so they are labelled "m" as part of that clothing line.

2T and a 24m are both made to fit 2 year olds, and can both be used interchangably.

The actual sizing of them is going to depend on brand. One brands 24m may be longer then its 2T. There are no real set rules on that, although usually the 2T, being part of the toddler line, will be made for longer slimmer kids (toddler builds).

This gets asked a lot. Consensus:

-- 2Ts tend to be taller than 24M sizes

-- 24M is wider and has snaps on the legs for diapers; 2T usually doesn't

Mostly it's just a clothing industry convention -- infant designs are made from 0-24mo, toddler from 2T to 5T or whatever, and then older kids' sizing takes over.

Further confusing it is the occasional existence of an "XXS" size which corresponds to "2-3"...

Length only. 2T shirts are longer in the waist. Same thing between 4T and 4. Its just longer.

I can never tell, either. Since one company's 2T is bigger than some other companies' 4T, it's hard to know what the differences are.

24 months is made to fit over a diaper.

2T is made to fit over regular underwear.