Amending tax filing status from MFS to MFJ

[maximgt]

Thank you for your response. This is still unclear.

As we know, 2 Forms 1040 were originally filed as MFS.

Here's my question - Which Form1040 should we use to amend the filing status (from MFS to MFJ)? Do we use the Taxpayer's Form 1040 or the Spouse's Form 1040, or do we file 2 Forms 1040-X to amend each of the previously filed Forms 1040? It is just logical that we cannot amend one Form 1040 and not the other. 

Can you please be specific when responding? Much appreciated.

[DMarkM1]

You only need to amend one.  I recommend using the more complicated one and adding in the other spouse's information.  The IRS will disregard the other MFS return once the amendment is processed.