Why Did the IRS Send Me a Certified Letter?

An IRS-certified letter is a legal notice delivered through USPS Certified Mail, which means the IRS needs documented proof that you received

IRS Letter 4464C Explained: Meaning, Refund Delay & What To Do (2026 Guide)

IRS Letter 4464C is an official IRS notice that tells you your tax return is under review and your refund is on