The Common Ledger library · 10 guides · Updated October 2026
Useful answers. Clear advice.
Straight answers to the tax and bookkeeping questions small businesses actually ask, written and checked by our CPAs. When you need more than an answer, we’re here.
Browse the stacks
All guides- TX Small business taxes Estimated taxes, deductions and the forms that come with running a business. 4 guides
- EN Business structure LLCs, S corps and when changing your structure saves money. 1 guides
- BK Bookkeeping Keeping clean books and reading the reports they produce. 3 guides
- PY Payroll and people Hiring, paying and classifying the people who work with you. 2 guides
What’s due next?
Pick what describes you. We count down to your next federal deadline.
The full calendar–days
Next deadline
- Extended individual and C corp returnsForm 1040, Form 1120
- Third-quarter payroll reportForm 941 (October 31 is a Saturday)
- C corp fourth-quarter estimated tax2026 estimates
- Fourth-quarter estimated tax for 2026Form 1040-ES
- W-2s, 1099-NECs and annual payroll formsW-2, 1099-NEC, Forms 940 and 941 (January 31 is a Sunday)
- S corp and partnership returns, and S corp elections for 2027Form 1120-S, Form 1065, Form 2553
- Individual and C corp returns, and first-quarter estimatesForm 1040, Form 1120, 2027 estimates
- First-quarter payroll reportForm 941
- Second-quarter estimated tax2027 estimates
- Second-quarter payroll reportForm 941 (July 31 is a Saturday)
- Third-quarter estimates and extended S corp and partnership returns2027 estimates, Form 1120-S, Form 1065
- Extended individual and C corp returnsForm 1040, Form 1120
Federal deadlines for calendar-year filers, already moved for weekends. Disaster relief can extend them and state dates differ, so confirm with your CPA.
Would an S corp save you money?
Move the sliders to compare self-employment tax with payroll tax on a reasonable salary.
Simplified estimate: 15.3% self-employment tax on 92.35% of profit, compared with 15.3% payroll tax on salary. It leaves out income tax effects such as the qualified business income deduction and the deductible half of self-employment tax. Not tax advice.
Most read this month
- TX 04Small business taxes5 min Form 1099-NEC: who gets one and the new $2,000 threshold Starting with payments made in 2026, the reporting threshold jumped from $600 to $2,000. Here’s who you still need to send forms to.
- TX 01Small business taxes5 min Quarterly estimated taxes: who pays and when If you’re self-employed or have income without withholding, the IRS expects tax four times a year. Here’s how to know if that’s you and how much to send.
- EN 01Business structure7 min S corp or LLC: when the switch actually saves money An S corp election can cut self-employment tax, but it adds payroll and paperwork. Here’s how to tell whether the math works for you.
- BK 02Bookkeeping6 min The month-end close checklist for small businesses Ten steps that turn a messy month into numbers you can trust, in about two hours.
Written by the people who’d do your taxes
Every guide is written or reviewed by a CPA on our team, and rechecked whenever the rules change.
About the firm- Grace Whitfield, CPAManaging partnerWrites most of the tax guides, and answers the hard questions.
- Omar Haddad, CPASmall business taxS corps, multi-state filings and anything with a K-1.
- Lena RuizBookkeeping leadRuns month-end close for 60 clients and keeps the checklists honest.
Didn’t find your answer?
Ask a CPA. Most questions get a reply within one business day.