What should I do about my mother claming me as an adult dependent on her taxes returns for multiple years and I Do not live with her haven't lived with her for 20 years?

[DianeW777]

File your return accurately and it may have to be mailed.  Only one return can be e-filed with the same social security number and name. If you file before she does, that prevents her from being able to e-file.  However if she files first it will likely be accepted.  

You have no control over what your mother may be doing on her return except to report her to the IRS and/or State Department of Revenue. You could file your return as early as possible, even if you are not required to file.

[VolvoGirl]

Have you been filing your own returns?   If you file and she claims you eventually the IRS will send you both letters to determine if she can claim you.   If you file and it rejects you can print and mail your return.  

[xmasbaby0]

And....get a six-digit IP pin----that will block anyone else from filing a return using your SSN.

6-digit IP NUMBER FROM IRS

https://content.govdelivery.com/accounts/USIRS/bulletins/2af48f0?reqfrom=share

to get your new PIN from the IRS

- https://www.irs.gov/identity-theft-fraud-scams/retrieve-your-ip-pin

[xmasbaby0]

Better one to use:

https://www.irs.gov/identity-theft-fraud-scams/get-an-identity-protection-pin