Summer’s Over: Your Final Tax Deadlines Are Here

Labor Day may mark the unofficial end of summer, but for taxpayers it kicks off something else entirely: crunch time. If you’ve been putting off your returns, the last stretch is here—and so are the penalties if you don’t act fast. Two critical deadlines are closing in: September 15 and October 15. These are the final deadlines. No more extensions, no second chances.

What Extensions Really Mean

Extensions only give you more time to file, not more time to pay. Any balance due has been accruing interest and penalties since the original due date. That means the longer you wait, the more expensive it gets.

September 15th: S-Corps and Partnerships

S-Corporations and Partnerships are pass-through entities, which usually means they don’t owe federal income tax at the business level. But that doesn’t protect them from brutal penalties:

• $245 per month, per shareholder or partner (capped at 12 months).
• Example: Two partners missing the deadline for a year = $5,880 in penalties.

And here’s the kicker: interest keeps compounding on those penalties until the return is filed. It’s a bleed that won’t stop until you act. Even if your business owes no tax, the penalties stack up just the same.

October 15th: Individual and C-Corp Returns

For individuals and C-Corporations, the IRS looks at unpaid taxes:

• Failure to File: 5% per month
• Failure to Pay: 0.5% per month

The smart move? File even if you can’t pay in full. The “failure to file” penalty is far steeper than the “failure to pay.”

Why Waiting Costs More

• Pass-throughs: Penalties apply whether or not you owe tax.
• Individuals & C-Corps: The bigger the balance, the bigger the penalty.
• Interest: Compounds daily (around 8% annually) on top of penalties.

Every day you wait, the IRS digs deeper into your pocket.

If You’re Not Ready

• Filed an extension? Get the return in now and pay what you can.
• Didn’t file one? Penalties are already running—filing stops the clock.
• Too overwhelmed? A tax professional can get you filed quickly and may even secure penalty relief.

Your Action Plan

• This Week: Gather your records and estimate what you owe.
• By Sept. 15: File all S-Corp and Partnership returns.
• By Oct. 15: File individual and C-Corp returns.
• After Filing: Put systems in place—estimated payments, clean bookkeeping—so you’re not here again next year.

This isn’t just about paperwork—it’s about stopping a financial bleed that grows every single day you wait.

Behind on filings? Facing mounting penalties? Contact Downie Business Solutions now at downiesolutions.com or email hello@downiesolutions.com. As an Enrolled Agent practice based in Brooklyn, NY, we help business owners nationwide stop penalties, cut interest, and get back on track.

Stop the penalties. Stop the interest. File today—before it costs you even more.