My accountant wants to e-file my federal and state 2016 tax returns. How do I get my wife's and my federal and state e-file license numbers?

[xmasbaby0]

There is no such thing as an e-file license number for the taxpayer.

[SteamTrain]

....Maybe the Driver's Lisc some states require????

You have that in your wallet...or talk to the accountant again to clear up what he/she is asking for.

[SweetieJean]

Your accountant should know that!
And please note that TT is not licensed for use by paid tax preparers.

[VolvoGirl]

I don't remember when it started but maybe he needs your 2015 AGI or PIN number to efile?

[Critter]

A paid tax preparer using a professional tax program does NOT need your 2017 AGI or PIN to efile a 2018 return...never has. 

[Critter]

And not all paid preparers can efile prior year returns ...so paper file instead.

[Anonymous]

if your tax preparer will be efiling 2016 then he won't be using Turbotax because the software doesn't allow it.  many professional programs do allow efiling of prior year returns even amended returns.