I got a letter from the IRS saying I need to pay more taxes for 2017 due to a mistake I made. I have paid what I owed which was less. Do I just pay the difference?

[mesquitebean]

"I have paid what I owed which was less."

Paid when???  Does that mean originally when you filed the 2017 return, or recently?    When you originally filed did you have taxes due, which you paid at the time, but it was not enough due to a preparation mistake?

What does the letter ask you to do?  Is it a bill wanting you to send in a certain amount?  Do they want anything else?

Do you agree with their determination and what they are asking for?

If you purchased Audit Defense, we can tell you how to contact the third-party company for help with an IRS letter.

Otherwise, you can phone TurboTax free Audit Support Center during business hours, and they can advise you on how to respond to an IRS letter.   To get the phone number go to the page linked below click, the blue "Get Help" button, and follow the prompts.

https://support.turbotax.intuit.com/irs-notice/audit-support/

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