older home 2x4 wall window replacement

[swanhaven]

Apologies in advance if this has been asked.
We have an older home that we will one day completely retrofit.
In the mean time there are several windows that are completely inadequate and need replacing asap - we live in a very cold climate.
Is it possible to install new high efficiency windows in a 2x4 wall that can then be carried over to our future retrofit to 6 or 8" walls?
We are not at the stage of gas filled/panes etc yet - we just want to know if it is possible to do.
Any suggestions or links to information are welcome
TIA

[Randy]

You can use any window you like. Later, you would just add jamb extensions to cover the new depth.

[Windows on Washington]

Yep. If the opening sizes aren't changing, you can always put it in or out. If you are thinking about adding wall depth, you want to make sure you get a window that is going to somewhat keep up with the performance of that wall.

[TheWindowNerd]

I agree with Eric,
So yes.

theWindowNerd.com

[swanhaven]

The dimensions would be the same yes.
Thank you all for your help!
Have a super weekend everyone