How do I fix inadvertent claiming of my son on my taxes so that his filing won't be rejected again? I assume I'll have to file an amended return to fix my mistake.

[dc9driver]

I inadvertently claimed my son as a dependent. I electronically filed my taxes. Accepted. When my son tried to file his taxes, they were rejected because he was already "claimed" on my taxes. It's now the 14th of April. 

I assume I need to amend my taxes, (via mail), and resubmit son's taxes. What is the soonest he can resubmit and not have his taxes rejected again? Did I mention it's April 14th? 

Does the rejection count as a "postmark" as far the the filing deadline? 

Does/do he/we need to file an extension?

Thanks.

[DavidK · Accepted solution]

You'll need to file an amended return.  You can do this electronically.  Your son will need to print and mail his taxes on the 15th.  The rejection does not count as a postmark, and if he attempts to file electronically again his return will be rejected again.  If your son files via mail on the 15th he does not need to file an extension.