How long do I have to respond to IRS Letter 1615?

Verify the exact identifier. Check the date and any response deadline printed on your notice, and follow the notice's instructions.

IRS Letter 1615: Verify the Letter Number

We could not verify this page's former description in current public IRS sources. Confirm the exact identifier and title on your document before acting.

Editorially reviewed by the Law Offices of Darrin T. Mish, P.A.Updated October 1, 2026

Notice: Letter 1615
Urgency: Attention
Deadline: Verify the exact identifier

Your first move

No current public IRS source confirms this page's former partnership-audit description. Use the exact title and instructions on your document.

Why this page is limited

We found no current public IRS source that reliably supports the description previously associated with Letter 1615. IRS letter numbers and suffixes matter, and a one-character difference can point to a completely different process.

What to do now

Check the upper-right corner of every page for the exact notice or letter number. Read the title, tax period, response date, and contact instructions printed on the document. Do not send records, call a number, or miss a deadline based only on an unverified web description.

Compare the document with the IRS notice-and-letter lookup linked below. If the number is not listed, call the verified IRS number for the issue or have a qualified tax professional review the actual letter.

Watch for close identifiers

Confirm every digit and suffix. For example, Letter 5071C is a documented identity-verification letter; that does not make Letter 507C the same document.

Want a second set of eyes on this letter?

Free consultation with Darrin T. Mish, a Tampa tax attorney licensed since 1993 and admitted to the U.S. Tax Court. Bring the letter.

Call (813) 229-7100

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