This is the note I'll be writing. Please let me know if I need to add anything else.
I tried calling IRS CS, but they kept passing me to the next person or hanging up on me even before I could get through my explanation.
To Whom It May Concern,
I am writing this letter to explain why I am filing my tax return by mail. My e-file was rejected because one of the dependent's Social Security number has already been used as a dependent on my mom's return. I have confirmed with my mother that she has claimed my brother as a dependent in her previous year's tax return, but this year I am the head of household and have provided more than half of my brother's support, including paying a larger share of the household rent.
My mother will be filing her 1040x to remove my brother as a dependent from her return, and I will be claiming him as a dependent on my tax return. I am providing all three Social Security numbers below to assist with the processing of my return:
My Brother's Social Security Number:...
My Mother's Social Security Number:...
I have included my W2s with my tax return, and I apologize for any inconvenience this may cause. If you require any further information or documentation, please do not hesitate to contact me.
Thank you for your attention to this matter.
Sincerely...
