Startup Financial Calendar Builder

At minimum, every startup should track quarterly estimated tax payments (April 15, June 15, September 15, January 15), annual tax return filing, state annual report filing, business license renewals, and monthly financial close. If you have employees, add W-2 distribution, quarterly 941 payroll filings, and FUTA. Use the cash flow forecast calculator to ensure you have funds available for each deadline.

Your fiscal year end determines when your annual tax return is due (typically 3-4 months after FYE), when you need to prepare annual budgets, and when audit or financial review periods occur. Most startups use a December fiscal year end, but some choose differently to avoid tax season congestion or align with business cycles. The calendar builder adjusts all recurring deadlines based on your chosen fiscal year end.

Key payroll deadlines include: W-2s to employees by January 31, W-2s filed with SSA by February 28, quarterly Form 941 payroll tax returns (January 31, April 30, July 31, October 31), annual Form 940 FUTA by January 31, and 1099-NEC forms to contractors by January 31. If you use a payroll service, most of these are handled automatically, but you still need to ensure they are filed correctly.

Startups should close their books monthly (within 10 days of month-end), conduct quarterly financial reviews comparing actuals to budget, and do a comprehensive mid-year review to adjust forecasts. Companies with investors should add monthly investor updates and quarterly board deck preparation. Track your burn rate monthly to catch cash flow issues early. Read our guide on building board-ready financial reports.

Missing tax deadlines can result in penalties and interest. The IRS failure-to-file penalty is 5% of unpaid taxes per month (up to 25%), and the failure-to-pay penalty is 0.5% per month. Underpayment of estimated taxes incurs roughly 8% annual interest. Filing extensions avoid the filing penalty but not payment penalties. Use the budget accuracy scorecard to ensure your tax reserves match your obligations.

Most early-stage startups under $1M revenue do not legally require an audit, but investors or lenders may request one. Companies above $250K revenue should consider an annual financial review (less rigorous than a full audit). Series A+ companies typically need audited financials. A financial review or compilation from a CPA can cost $5K-$15K, while a full audit ranges from $15K-$50K+ depending on complexity.