Tax Extension Help for Individuals and Businesses
If you filed an extension in the spring, the clock is now short. We prepare extended individual returns due October 15 and extended S-corp and partnership returns due September 15, take over from a previous preparer where needed, and request penalty relief where the facts support it.
Extended filing deadlines
An extension is six months for individuals and C-corporations, and six months for S-corps and partnerships from their earlier original deadline. That produces the following schedule for calendar-year filers.
| Return | Original deadline | Extended deadline | Extension form |
|---|---|---|---|
| Individual (1040) | April 15 | October 15 | Federal Form 4868 |
| S-corporation (1120-S) | March 15 | September 15 | Federal Form 7004 |
| Partnership / multi-member LLC (1065) | March 15 | September 15 | Federal Form 7004 |
| C-corporation (1120) | April 15 | October 15 | Federal Form 7004 |
This season: extended S-corp and partnership returns are due September 15, 2026, and extended individual returns are due October 15, 2026. If you own an S-corp or partnership, your business return comes first, because your personal return cannot be completed until your K-1 exists.
An extension buys time to file, not time to pay
This is the part that costs people money. An extension moves your filing deadline and nothing else. Any tax you owed was still due on the original date, and interest accrues from that date regardless of the extension.
The penalty structure explains why filing on time matters so much even when you cannot pay:
- Failure to file: 5% of the unpaid tax per month, capped at 25%
- Failure to pay: 0.5% of the unpaid tax per month, also capped at 25%
The filing penalty is ten times the payment penalty. Filing a return you cannot fully pay is almost always cheaper than not filing, and a payment plan is usually available afterward. Late S-corp and partnership returns work differently again: they are penalized per owner per month, so a multi-owner company can accumulate a real bill even in a year with no taxable income.
When we file an extension, we estimate what you owe first and get that paid, which limits the interest and keeps the failure-to-pay penalty small.
How we handle an extended return
1. Establish what is actually missing
Usually a return is still open in September for one of three reasons: the books are not closed, a K-1 has not arrived, or nobody has chased the missing documents. We identify which it is on the first call so the remaining time goes to the real bottleneck.
2. Fix the underlying records
If self-employment or entity books need work before the return can be prepared, we quote that cleanup separately rather than burying the hours in the return fee.
3. File and address the penalties
We prepare and file the federal and California returns, then request first-time abatement or reasonable-cause relief where the circumstances support it, and set up a payment plan if one is needed.
If you never filed an extension
File anyway, and file soon. The failure-to-file penalty keeps accruing every month the return is outstanding, so the cost of waiting compounds. Coming forward voluntarily also puts you in a far stronger position to request relief than being contacted first by the IRS or the Franchise Tax Board.
We regularly bring clients current on several years at once, reconstruct the bookkeeping behind those years, and negotiate the penalties afterward. If the notices have already started arriving, that becomes an IRS notice resolution engagement alongside the filings.
Related services
Individual Tax Preparation
Form 1040 preparation and published per-return pricing, whether you are on extension or filing on time.
Business Tax Returns
1120-S, 1065, and 1120 filings with K-1s for owners, including the September extended deadline.
Pricing
Published fees for every return type, so you know the number before the deadline pressure starts.