S Corp Tax Deduction Checklist 2026: What to Write Off

Table of Contents

• Your S Corp Tax Deduction Checklist for 2026

• S Corp Business Expenses Checklist: What You Can Write Off

• S Corp Tax Preparation Checklist: Records to Keep

• Frequently Asked Questions

Last Updated: October 17, 2026

Your S Corp Tax Deduction Checklist for 2026

If you just elected S Corp status and you're staring down your first filing season, here's the short version: your S Corp tax deduction checklist in 2026 starts with ordinary and necessary business expenses, then moves through officer compensation, retirement contributions, and a paper trail that can survive an audit. At McCrary Tax Prep, we walk S Corp shareholders through this exact sequence every year.

An S Corp doesn't pay federal income tax at the entity level. Deductions flow through to your personal return on IRS guidance on S corporation filing requirements, so every write-off you miss hits your own pocketbook.

S Corp Business Expenses Checklist: What You Can Write Off

The S Corp business expenses checklist is the working core of your return: rent, utilities, office supplies, professional fees, business insurance, vehicle costs, travel, and meals, each deductible when it's ordinary and necessary for your trade, per the publication on deductible business expenses.

Work through these categories and note your documentation for each:

1. Startup and organizational costs. Legal and accounting setup fees incurred before you opened your doors.

2. Vehicle expenses. Standard mileage rate or actual costs, pick one and stick with it.

3. Home office. Only for space used regularly and exclusively for business.

4. Business meals and travel. Meals need a business purpose; travel must be away from your tax home and primarily for business.

5. Employee wages and officer compensation. Covered below.

6. Health insurance premiums and benefits. Special treatment for shareholder-employees.

7. Retirement plan contributions. Employer contributions to a qualified plan.

8. Depreciation and equipment. Section 179 and bonus depreciation let you write off qualifying equipment faster.

Your salary is a deduction to the corporation, and it must be reasonable for the work you do. Set officer compensation too low and the IRS can recharacterize distributions as wages, triggering payroll tax you didn't plan for.

Watch Out Paying yourself nothing in wages while taking large distributions is the fastest way to invite scrutiny. Payroll taxes follow reasonable compensation, and the IRS has challenged this arrangement repeatedly.

For a shareholder-employee owning more than 2% of the company, health premiums are generally included in W-2 wages and then deducted on your personal return, following the IRS rules for S corporation shareholder health insurance. Get the W-2 reporting wrong and you lose the deduction.

An accountable plan reimburses shareholder-employees for business costs tax-free when there's a business connection, substantiation, and return of excess advances, keeping reimbursements off the W-2.

Expense Category	Who Claims It	Key Record
Officer wages	Corporation	Payroll reports and W-2
Vehicle costs	Corporation	Mileage log or receipts
Home office	Shareholder-employee	Square footage and utility records
Health premiums	Shareholder-employee	Policy statements and W-2 entry
Accountable plan reimbursements	Corporation	Expense reports and receipts

S Corp Tax Preparation Checklist: Records to Keep

The S Corp tax preparation checklist comes down to documentation: keep receipts, bank statements, mileage logs, payroll records, and a reconciled general ledger for every deduction you claim. Your return runs on Form 1120-S, and each shareholder receives a Schedule K-1 reporting their share of income, deductions, and credits.

Book now →

Gather these in one place as the year closes:

• Bank and credit card statements reconciled to your books

• Receipts for every expense over your recordkeeping threshold

• Mileage log with dates, destinations, and business purpose

• Payroll reports, W-2s, and quarterly filings

• Health insurance policy statements

• Retirement plan contribution records

• Prior-year return and K-1s

Store the supporting documentation for at least three years after filing, longer if you claim a loss or the IRS questions an item. A bank statement shows the money left, not why, the receipt and a note on business purpose are what hold up.

Pro Tip Snap a photo of every receipt the day you get it and drop it into a folder named for the tax year. Come filing season, you're sorting photos, not hunting through a shoebox.

This is also where a good preparer earns their keep, someone who reads your K-1, checks your reasonable compensation against your distributions, and asks about the accountable plan you never set up. That's the kind of work our S-Corp taxes service covers, and if you're still weighing entity choices or setting up payroll for the first time, a Small Business Consultation can get you pointed in the right direction before the year gets away from you.

---

Filing an S Corp return for the first time is where small oversights turn into real money. If you'd rather not sort through officer compensation, accountable plans, and health insurance reporting on your own, McCrary Tax Prep handles S Corp filings year-round with transparent pricing and fast turnaround, backed by a Certified Small Business Consultant on staff. Book your consultation with McCrary Tax Prep and get your 2026 filing done right the first time.

Frequently Asked Questions

What expenses can I write off for my S Corp?

Ordinary and necessary business expenses are the baseline: rent, utilities, office supplies, professional fees, business insurance, vehicle costs, and home office expenses if you qualify. Add employee wages and officer compensation, payroll taxes, retirement plan contributions, and health insurance premiums for shareholder-employees under an accountable plan. Keep supporting documentation for every line. A written S Corp tax deduction checklist helps you catch the big items and the small ones, and it keeps your records audit-ready.

Can an S Corp deduct health insurance for shareholder-employees?

Yes, if the S Corp sets up a written accountable plan and pays the premiums or reimburses the shareholder-employee. The premiums are then deducted by the S Corp and excluded from the shareholder's wages. The 2% shareholder rule applies: more-than-2% shareholders must include the premiums in their W-2 wages, then claim the self-employed health insurance deduction on their personal return. Work with a tax professional to document the plan and get the W-2 reporting right.

What records should a new S Corp owner keep for tax deductions?

Keep receipts, bank and credit card statements, mileage logs, home office measurements, payroll reports, W-2s, Form 1120-S drafts, Schedule K-1s, and any accountable plan reimbursements. Store them for at least three years after the return is filed, longer if you have unresolved issues. A simple folder system by expense category works fine. Good records are the difference between a deduction you can defend and one you have to give back.

Book now