Business Tax Strategy & Preparation

Filing once a year is a requirement. Planning once a year is a missed opportunity. The decisions you make throughout the year (timing purchases, structuring compensation, reinvesting profits) move your tax bill far more than anything that can be done after December 31st.

Deadlines vary by entity type, but here are the key dates for calendar-year businesses:

• January 31: W-2s and 1099s due to recipients and the IRS
• March 15: Federal return due for S-corps and partnerships (extended to Sept. 15)
• April 15: Federal return due for C-corps and sole proprietors (extended to Oct. 15)
• April 15, June 15, September 15, January 15: Quarterly estimated federal tax payment due dates for sole proprietors and owners of S-corps and partnerships (certain state passthrough tax deadlines may vary slightly)
• April 15, June 15, September 15, December 15: Quarterly estimated federal tax payment due dates for C-corps
• Quarterly: In general, Missouri state withholding and applicable sales tax filings are due quarterly, though deadlines may vary by filing type depending on your business.

For most businesses (S-corps, partnerships, LLCs, and sole proprietorships), income passes through to the owner's personal return and gets taxed at individual rates. That means the two returns are tightly linked, and a decision on one affects the other. Coordinating both with our team means those decisions get made on purpose, not reconciled after the fact.

Both. Whether you're launching something new or wondering if your current structure still fits, entity selection is one of the highest-leverage tax decisions you can make. The right answer depends on your income, growth plans, and ownership structure, and it often shifts over time. A periodic review is worth doing even for a well-established business.

Whether you're a pass-through entity or a C-corporation, the IRS generally expects tax to be paid as income is earned, not just settled up at year-end. Falling short of the required threshold can trigger underpayment penalties even if you pay in full by April. Because the right amount depends on how your year is trending, it's worth revisiting each quarter rather than setting a number in January and letting it ride.

No, and this is one of the most common misconceptions in business taxes. An extension buys you more time to file, not more time to pay. Any tax owed is still due on the original deadline. Underpay and settle later, and interest and penalties accrue on the difference. Extensions are a useful tool, but only when they're paired with a solid payment up front.

Don't ignore it, but don't panic either. Most notices aren't audits. Many are routine requests for clarification or minor corrections. What matters is understanding exactly what's being asked before you respond, since a misstep can turn a simple issue into a complicated one. Bring the notice to your Whitlock advisor before you act. That's always the right first step.

If your organization is selected for examination, you have the right to be represented by a licensed CPA, and you don't have to talk directly with auditors. Representation means reviewing the scope of the exam, organizing requested documentation, and advocating for your position throughout the process. We can step in at the start of an audit or at any point along the way, though the earlier we're involved, the better positioned you'll be.