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What We Handle

Not sure what notice you received? Start here.

You do not need to know the notice number or understand the letter before starting. We focus on common IRS tax notices that can usually be reviewed through the notice itself, supporting documents, and a clear written response plan.

Common notices we review

These often fit the Think Twice Tax review.

These are examples of notices and situations that often fit the Think Twice Tax review process. Final eligibility depends on what your notice says.

Some notices can be reviewed for explanation and next step clarity even when the underlying matter requires outside professional representation. Think Twice Tax does not provide levy representation, appeals representation, Tax Court representation, legal representation, or power of attorney services.

CP05 / Refund Hold for Review
The IRS is holding your refund while it reviews items on your return.
CP05A / Documentation Requested
A follow-up to a CP05 asking for specific documents to support your return.
CP11 / Return Changes
The IRS made changes to your return and says you owe additional tax.
CP12 / Refund or Overpayment Adjustment
The IRS corrected an error on your return, changing your expected refund amount.
CP13 / Changes, No Balance or Refund
The IRS corrected your return, and the adjustments offset, leaving no balance due or refund.
CP14 / Balance Due, First Notice
The IRS is notifying you that you have an unpaid balance on your account.
CP59 / Unfiled Return Notice
The IRS has no record of a return being filed for a prior year.
CP75 / CP75A — Documentation Requested
The IRS is asking for proof to support a credit, dependent, or filing status claimed.
CP90 / Final Notice of Intent to Levy
A formal notice giving you the right to a hearing before the IRS levies your property.
CP501 / Balance Due Reminder
A reminder that you still have an unpaid balance from a previous notice.
CP503 / Second Reminder
A more urgent reminder that a previous balance still hasn't been paid.
CP504 / Intent to Levy Warning
A serious notice warning that the IRS may levy your state refund if the balance isn't resolved.
CP523 / CP623 — Installment Agreement Default
The IRS says you've defaulted on a payment plan and may terminate it.
CP2000 / Underreported Income
Income, deductions, or credits reported to the IRS don't match your return.
CP2501 / Income Discrepancy Inquiry
Reported income doesn't match IRS records, and you're asked to respond before changes are proposed.
CP2566 / Proposed Assessment, No Return Filed
The IRS calculated a proposed tax based on third-party income since no return was filed.
CP3219A / Notice of Deficiency
A formal notice giving you 90 days to petition Tax Court over a proposed increase.
CP3219N / Notice of Deficiency, No Return Filed
A formal notice giving you 90 days to file or petition Tax Court when no return was filed.
4883C / Identity Verification
The IRS needs to verify your identity before continuing to process your return.
5071C / Identity Verification
The IRS needs to verify your identity, often through an online verification option.
LT11 / Letter 1058 — Final Notice of Intent to Levy
The letter version of a Final Notice of Intent to Levy, with the right to request a hearing.
Letter 12C / Information Requested
The IRS needs additional information or documents before it can finish processing your return.
Letter 4800C / Proposed Credit Adjustment
A proposed change to a refundable credit or withholding amount claimed on your return.
Documentation Request
The IRS may be asking for records before adjusting or releasing something.
Not Sure / Other
If you are unsure what you received, upload it and we will help identify what it appears to be.

Scope

What we do not handle in this review

Some situations require one-on-one professional representation or legal counsel beyond a flat notice review. If your notice is outside our scope, we will tell you clearly and explain what type of help may be needed.

If your matter is outside the paid review scope, your initial summary can still help identify what you received and what type of professional help may be appropriate. Clearly ineligible matters are not moved into the $45 review.

  • Audits or examination representation
  • Appeals, Tax Court, or legal disputes
  • Liens, levies, garnishments, or active collection enforcement
  • Offers in compromise or complex payment negotiations
  • Large or complex balances requiring professional representation
  • Cases requiring direct IRS contact or power of attorney

Not sure if your notice qualifies?

Start with your free notice summary and get clarity before you decide what to do next.