The Money Pocket · Checklist + calendar
Self-Employed Tax Kit
The estimated-tax calendar, the safe-harbor rule that kills penalties, and a 30-item deduction checklist for 1099 workers and side hustlers.
Updated October 9, 2026 · themoneypocket.com
Quarterly estimated tax calendar
| Income earned | Due date (tax year 2026) | Due date (tax year 2027) |
|---|---|---|
| January 1 – March 31 | April 15, 2026 | April 15, 2027 |
| April 1 – May 31 | June 15, 2026 | June 15, 2027 |
| June 1 – August 31 | September 15, 2026 | September 15, 2027 |
| September 1 – December 31 | January 15, 2027 | January 18, 2028 |
Pay through IRS Direct Pay or EFTPS (choose “1040-ES”). If a date falls on a weekend or legal holiday, the deadline moves to the next business day. States with an income tax usually follow the same calendar.
The safe-harbor rule (how to owe zero penalty)
You avoid the underpayment penalty if your withholding plus timely estimated payments cover the smaller of:
- 90% of this year’s tax, or
- 100% of last year’s tax — 110% if last year’s AGI was over $150,000 ($75,000 married filing separately).
There’s also no penalty if you owe less than $1,000 after withholding and credits. Easiest system: take last year’s total tax (Form 1040, line 24), multiply by 100% or 110%, divide by four, and pay that each quarter.
Self-employment tax, step by step
- Net profit from Schedule C (income minus deductions). Example: $60,000.
- Multiply by 92.35% → $55,410.
- Multiply by 15.3% → $8,477.73 self-employment tax (12.4% Social Security up to the $184,500 wage base, minus any W-2 wages, plus 2.9% Medicare on everything).
- Deduct half — $4,238.87 — on Schedule 1 when you compute income tax.
- Add income tax on top. Budget rule of thumb: set aside 25–30% of profit until you’ve run your real numbers.
Run it: 1099 tax calculator · side-hustle calculator · S-corp payroll calculator.
Retirement plans for the self-employed (2026)
| Solo 401(k) | $24,500 employee deferral (+$8,000 age 50+, or +$11,250 age 60–63) plus employer contribution of 20% of net self-employment earnings; total cap $72,000 before catch-ups. |
| SEP IRA | Up to 20% of net self-employment earnings (25% of W-2 pay from your own S-corp), max $72,000. |
QBI deduction
Most sole proprietors, partners, and S-corp owners can deduct up to 20% of qualified business income. Below taxable income of $201,750 (single) / $403,500 (joint) the deduction is generally available in full, including for service businesses; above that, wage and service-business limits phase in. Check yours with the QBI calculator.
Information-return thresholds
- Form 1099-NEC / 1099-MISC: payments of $2,000+ (starting with 2026 payments; was $600).
- Form 1099-K from payment apps and marketplaces: over $20,000 and 200 transactions.
- All income is taxable even if you never receive a form.
The 30-deduction checklist
| ✓ | Deduction | Notes |
|---|---|---|
| ☐ | Home office | Regular, exclusive business use. Simplified method: $5 per sq ft, up to 300 sq ft. |
| ☐ | Business mileage | IRS standard mileage rate or actual costs × business-use %. Keep a log. |
| ☐ | Health insurance premiums | Self-employed health insurance deduction, if you’re not eligible for an employer plan. |
| ☐ | Half of self-employment tax | Deducted automatically on Schedule 1 — make sure your software does it. |
| ☐ | Retirement contributions | Solo 401(k) or SEP IRA — often the single biggest deduction available. |
| ☐ | Phone & internet | Business-use percentage of the bill. |
| ☐ | Software & subscriptions | Accounting, design, scheduling, cloud storage, AI tools used for work. |
| ☐ | Equipment & computers | Section 179 or 100% bonus depreciation (restored by OBBBA for property acquired after Jan 19, 2025). |
| ☐ | Office supplies | Paper, ink, postage, small tools. |
| ☐ | Professional services | Accountant, attorney, bookkeeper, tax-prep fees for the business part. |
| ☐ | Business insurance | Liability, E&O, equipment insurance. |
| ☐ | Advertising & marketing | Ads, website hosting, domain, business cards, promo samples. |
| ☐ | Education | Courses that maintain or improve skills in your current business. |
| ☐ | Travel | Airfare, lodging, and transport for business trips away from home. |
| ☐ | Meals | 50% of business meals with clients or while traveling. |
| ☐ | Payment & bank fees | Stripe/PayPal/Square fees, business account fees. |
| ☐ | Contract labor | Payments to freelancers (Form 1099-NEC required at $2,000+ from 2026). |
| ☐ | Licenses & permits | Business licenses, professional dues, certifications. |
| ☐ | Rent & coworking | Office or coworking membership. |
| ☐ | Shipping & packaging | Postage, boxes, fulfillment fees. |
| ☐ | Inventory & materials | Cost of goods sold for product businesses. |
| ☐ | Platform fees | Marketplace, app-store, and creator-platform cuts. |
| ☐ | Interest on business debt | Credit card or loan interest for business purchases. |
| ☐ | Startup costs | Up to $5,000 deductible in year one (phase-out above $50,000 of costs). |
| ☐ | Tools & uniforms | Items required for the work and not suitable for everyday wear. |
| ☐ | Utilities | Business share of electricity, heat, water (via home office). |
| ☐ | Repairs & maintenance | Of business equipment and vehicles (actual-cost method). |
| ☐ | HSA contributions | If you have a qualifying high-deductible health plan. |
| ☐ | Qualified business income (QBI) | Up to 20% of qualified business income — see below. |
| ☐ | Bad debts | Accrual-basis businesses only, for income already reported. |
Sources: IRS Form 1040-ES instructions, Publication 334, Publication 505; Rev. Proc. 2025-32; Notice 2025-67; One Big Beautiful Bill Act (Pub. L. 119-21). Informational only — confirm with the IRS or a tax professional.