Form 4868 is the IRS application for an automatic 6-month extension to file your federal individual income tax return (like Form 1040). California residents mailing it without payment typically send it to Department of the Treasury, Internal Revenue Service, Fresno, CA 93888-0014 ; with payment, use Internal Revenue Service, P.O. Box 802501, Cincinnati, OH 45280-2501 (confirm via IRS site as addresses can update yearly).

Note : Always double-check the official IRS "Where to File" page for Form 4868 (irs.gov) or instructions PDF, as state-based addresses vary by payment status and processing center. E-filing via IRS Free File or software is often faster and recommended over mail.

Mailing Addresses for California

Use this table for Form 4868 (federal extension only; California auto-extends with federal but may need FTB Form 3519 if payment due).

Scenario| Mailing Address
---|---
No Payment| Department of the Treasury
Internal Revenue Service
Fresno, CA 93888-0014 5
With Payment| Internal Revenue Service
P.O. Box 802501
Cincinnati, OH 45280-2501 5

California State Extension (FTB 3519)

  • California Franchise Tax Board (FTB) automatically grants extension if federal is filed, but mail Form 3519 payments to: Franchise Tax Board, P.O. Box 942867, Sacramento, CA 94267-0001.
  • No form needed without payment; just file by Oct 15.

Quick Tips from Forums & Trends

  • Reddit users note : Cut along the dotted line on Form 4868 and mail only the bottom stub—full pages unnecessary.
  • 2026 Deadline : Postmark by April 15 (or next business day); extensions don't extend payment due date—pay estimates to avoid penalties.
  • Trending advice: Go digital! IRS e-file confirmations are instant vs. mail delays.

Why Mail vs. E-File?

Mailing works if no access to software, but forums buzz about lost mail issues—track with certified mail. For 2025 taxes (filed 2026), IRS emphasizes electronic for speed.

TL;DR : Fresno, CA without payment; Cincinnati, OH with. Verify IRS.gov; consider e-file. Information gathered from public forums or data available on the internet and portrayed here.