Letter 1948-C: how to request a 972CG extension
Notice 972CG gives you 45 days from the notice date to respond. If you cannot assemble the response in time, the procedure provides one written extension — and the IRS answers it with Letter 1948-C. Here is how the request works, what it must contain, and where it goes.
1. What Letter 1948-C is
Letter 1948-C is the IRS's reply letter in the 972CG process. It confirms the extension of your response deadline — and it is also the letter the IRS uses to request additional information during review. Receiving a 1948-C about an extension means the IRS has acted on your request; read it for the new response date, which may differ from what you asked for.
The extension is not automatic and not assumed: it exists only once the IRS grants it in writing. Until then, the original 45-day response date controls. For the full response sequence, see how to answer Notice 972CG.
Source: IRM 4.19.25.
2. The extension you can get
The procedure provides one written extension. The standard grant is 30 additional days; if you specifically request a longer period, the extension can run up to 90 days from the notice date. Ask for the full period you need — the IRS answers with Letter 1948-C either way, and the letter states the date it granted.
Measure the ceiling from the notice date, not from when the notice arrived or from the original response date. Use our free 45-day deadline calculator to calendar the original date first, then layer the extension on top.
3. What the written request must include
Phone requests do not satisfy the procedure — the request must be in writing. A complete request contains:
- The notice number (972CG) and the notice date as printed on your notice.
- Your employer identification number (EIN) and the tax year the notice covers.
- The extension requested: the standard 30 days, or a specific longer period (up to 90 days from the notice date).
- A brief reason for the request — for example, gathering correction records or solicitation documentation.
- Your signature and contact information.
Keep the reason factual and short. The IRS is evaluating a procedural request, not the merits of your reasonable-cause position — save the substantive statement for the response itself (see 972CG reasonable cause, explained).
4. Where to send it — and when
Send the request to the IRS address printed on the notice — not a generic service center. If the notice lists a fax number, a faxed request with a retained transmission receipt satisfies the written requirement and gives you same-day proof of sending.
Timing: send it well before the response date. A request faxed on the deadline itself may not be acted on in time — and an ungranted request leaves the original date in force. Tracked delivery (certified mail or equivalent) with a retained receipt is the fallback if you mail it.
Sources: IRM 4.19.25; What is Letter 972CG?
5. After the extension is granted
Letter 1948-C states your new response date. Calendar it immediately — the extension is a one-time procedure, and the extended date is firm. Use the extra time for the two things that consume the most preparation:
- Correction records. Correction timing sets the penalty tier, so file corrections before the response date where possible — the corrected 1095-Cs (X in the CORRECTED box, 1094-C transmittal not marked corrected, employee copies furnished) and their dates feed the tier math.
- Reasonable-cause documentation. The written statement under Reg. §301.6724-1(m) needs facts, dates, and the declaration under penalties of perjury — gather the solicitation records and supporting documents while the clock is extended.
The 972CG Response Pack ($129) recomputes your penalty tier-by-tier, tracks corrections and their timing, and assembles the written statement and response packet.
Common questions
The IRS answers with Letter 1948-C — a standard 30-day extension (up to 90 days from the notice date if specifically requested).
No. The response date printed on your notice keeps running until the IRS grants the extension in writing. Request the extension early enough for the IRS to act on it before the deadline.
The request must be in writing. Include the notice number, the notice date, your EIN, the tax year, the extension you are requesting (30 days, or a specific longer period up to 90 days from the notice date), a brief reason, your signature, and contact information.
To the IRS address on the notice — not a generic service center. Keep proof of mailing (tracked delivery) or the fax transmission receipt.
The procedure provides one written extension. If the granted extension is not enough, contact the IRS before the extended date expires — any further relief is discretionary.
This guide is general information, not legal or tax advice. Statutes and IRS pages change — verify against the sources linked above.