Can I just file my federal taxes and mail my state tax return?

[taxmanfries]

I want to file my federal taxes online, but mail in my state taxes.

[BobSimThinker]

Yes, you can. You are not required to eFile both. 

[AnnetteB6]

Yes, you can choose to electronically file your Federal return and mail your state return (unless your state required electronic filing).

As you go through the filing options you can choose how to file each return.  

@taxmanfries