I was thinking of buying a new neck for my strat, but the neck Iwant to buy has 21 frets, and my strat originally came w/ 21 frets.

Is it possible to put a 22 fret neck on a 21 fret guitar?
Gibson Les Paul Traditional
Crate V33 212 Combo
DigiTech Whammy IV
Dunlop Crybaby
MXR Classic Distortion
Ibanez DE-7 Delay
Boss GE-7 Equalizer

If the neck's are the same scale length, it could work. The 22 fret neck would likely extend onto to the body. You could do some body work to better accommodate the 22 fret neck
" When the power of love overcomes the love of power, the world will know peace."-Jimi Hendrix
I don't see why not. It might mess up the sound a little bit, because the neck pickup on a strat is placed at the position where the 24th fret would be, making it more harmonically good or something like that.

to answer your question though, there's no reason why you wouldn't be able to put the 22 fret neck on, as long as it fits in the slot.