The IRS mails letters or notices to taxpayers for a variety of reasons including:
They have a balance due.
They are due a larger or smaller refund.
The IRS has a question about their tax return.
They need to verify identity.
The IRS needs additional information.
The IRS changed their tax return.
Here are some do's and don'ts if you receive a letter from the IRS:
DON'T ignore it. Most IRS letters and notices are about federal tax returns or tax accounts. The notice or letter will explain the reason for the contact and give instructions on what to do.
DON'T panic. The IRS and its authorized private collection agencies typically contact people by mail. Most of the time, all you need to do is read the letter carefully and take the appropriate action.
DO read the notice. If the IRS changed your tax return, you should compare the information provided in the notice or letter with the information in your original return. There is generally no need to contact the IRS if you agree with the notice.
DO respond timely. If the notice or letter requires a response by a specific date, you should reply in a timely manner to minimize additional interest and penalty charges and preserve your appeal rights if you don’t agree.
DO pay amount due. You should pay as much as you can, even if you can’t pay the full amount. You can pay online or apply for an Online Payment Agreement or Offer in Compromise. The IRS offers several payment options.
DO keep a copy of the notice or letter. It’s important to keep a copy of all notices or letters with your other tax records. You may need these documents later.
DO remember there is usually no need to call the IRS. If you must contact the IRS by phone, use the number in the upper right-hand corner of the notice. You should have a copy of your tax return and letter when calling. Typically, you only need to contact the IRS if you don’t agree with the information, if the IRS requests additional information, or if you have a balance due. You can also write to the IRS at the address on the notice or letter. If you write, allow at least 30 days for a response.
DO avoid scams. The IRS will never contact you using social media or by text message. The first contact from the IRS usually comes in the mail. If you're unsure if you owe money to the IRS, you can View Your Account Information on the IRS website.
Resources: Understanding Your IRS Notice or Letter Tax Topic 651, Notices – What to Do Tax Topic 653, IRS Notices and Bills, Penalties, and Interest Charges Tax Topic 654, Understanding Your CP75 or CP75A Notice Request for Supporting Documentation