Can the irs tell me if someone other than myself has claimed my children on their tax return?

[DoninGA]

No.  The IRS will not tell you if someone else filed a tax return with either yours, your spouse's or a dependent's name and Social Security number.

[Bsch4477]

No one will tell you before you file. If someone else claimed them and then you file claiming them, your return will be rejected. 

[DianeW777]

They will only  tell you if you have claimed a dependent that was already included in another tax return.  They scrutinize the last name, social security number (SSN) and the date of birth for that reason.

This is the only way you will know and at that time they will require documentation to prove it is your child.  The form below will help you figure out what you might need should some else try to claim your child,

Supporting Documents (Form 14815)

@037f95e66a3b 

[xmasbaby0]

No.  The IRS will not tell you.    If your e-file is being rejected with a message that the SSN (s) have already been used, it is likely that someone else did claim the children or used the SSN even by mistake.  You cannot fix that problem yourself.   The only way for you to file and claim your child(ren) is to print, sign and mail your tax return.  The IRS will sort out the duplicate use of the SSN.   If someone (other parent?   old GF?  old BF?)  claimed them and they should not/could not claim them, they will face penalties and repayment of any child-related refund they received.

When you mail a tax return, you need to attach any documents showing tax withheld, such as your W-2’s or any 1099’s.  Use a mailing service that will track it, such as UPS or certified mail so you will know the IRS/state received the return.

Federal and state returns must be in separate envelopes and they are mailed to different addresses.  Read the mailing instructions that print with your tax return carefully so you mail them to the right addresses.

[AmyC]

Sometimes the child files their first return and forgets to mark that they can be claimed. It could be the other parent claiming the child, it can be a mistake - those still happen. You will have to mail your return and write a letter explaining that you tried to e-file but could not. Explain your position with any relevant information. Do use tracking to ensure the safe arrival of your information.

References:

When Both Parents Claim a Child

Dependent Dilemmas