Updated August 7, 2026. Quick answer: New York’s most common personal-income-tax letter is a Request for Information — Form DTF-948 or DTF-948-O. 🔴 It is not an assessment and not a bill. It is New York holding your refund until you prove something you already claimed. Responding by the date on the letter is what restarts processing.
First, identify what you are holding
New York’s own instruction is mechanical and it is the most useful sentence on their site:
To identify the letter you received, locate the form number in its bottom-left corner.
Do not go by the wording of the first paragraph. The Tax Department sends many letters whose opening lines read similarly; the form number is what tells you which process you are in. DTF-948 and DTF-948-O are the Request for Information letters.
Why one arrives
The Department publishes the common reasons, and they are almost all verification rather than accusation: verifying wages and withholding for New York State, New York City or Yonkers; verifying that you lived or worked in one of those jurisdictions; a credit claimed without its form attached; eligibility for claimed credits or itemized deductions; a dependent’s Social Security number or date of birth; and information about rental real estate income or loss, or income from a partnership, S corporation or trust.
⚠️ “You claimed a credit and we did not receive a copy of the form” is a paperwork failure, not a dispute. A large share of these letters are asking for a document that simply did not travel with the return.
🔴 You can usually read it before it arrives
This is the practical edge almost nobody uses. New York states that a mailed RFI letter can be viewed in the Document Summary of an Individual Online Services account, “as well as any other documents we sent you within the last three years” — and explicitly, “this means you can access a copy of your letter before it arrives in the mail and respond sooner.”
If your refund status says a letter was sent, you do not have to wait for the post. And the three-year archive is worth knowing about independently: it is where a letter you have already lost still lives.
What a good response looks like
New York publishes checklists of acceptable proof rather than leaving it to guesswork — separate ones for wages and withholding, child and dependent care expenses, the child or dependent relationship, college tuition, itemized deductions, self-employment income, business loss, rental loss, and driver income and expenses.
Matching the checklist is the whole job. These letters are decided on whether the documents you send are the documents on the list, not on the persuasiveness of an explanation.
Where a letter includes a questionnaire and you need more space, the Department names the forms to download: AU-262.3 (Nonresident Audit Questionnaire) and AU-262.55 (Income Allocation Questionnaire).
The date on the letter is the deadline
There is no general statutory window quoted here because New York does not publish one for this letter class — the operative deadline is the date printed on your own letter, and the Department’s instruction is to respond by it “so we can continue processing your return.” ⚠️ We are not printing a number of days. Anything you read that quotes a fixed count for an RFI is generalising something the Department states per letter.
What this page does not cover
This decodes an information request. It does not cover collection instruments — warrants, levies, income executions — and it does not advise on paying or settling a balance. An unanswered RFI can lead to an adjustment and eventually a balance; that is a factual sequence, not this page’s subject.
Sources
Quotations from the New York State Department of Taxation and Finance, Respond to a letter requesting additional information, retrieved 7 August 2026. Form numbers and checklist names are the Department’s own.
Related: the state tax notices index · California’s equivalent quirk: the FTB code table.