You don’t file anything to create a sole proprietorship. The moment you start doing business as the sole owner, you are one. There’s no formation document, no Secretary of State filing, no state-issued certificate that brings the business into existence. What you may need to file depends on the specifics: whether you’ll use a business name, hire anyone, sell taxable goods, work in a licensed field, or operate from home. Learning how to open a sole proprietorship is really about identifying which of those triggers apply to you and handling each one.
If you plan to freelance under your own legal name, have no employees, and sell services rather than taxable goods, you may not need to file anything at the state or county level. You’ll still report the income on your federal tax return, but that’s a tax obligation, not a registration.
What Triggers a Filing
Paperwork comes in when any of these apply:
- You operate under a name other than your full legal name. That requires a fictitious name registration (a DBA).
- You hire employees. You’ll need an Employer Identification Number and must register for payroll taxes.
- You sell taxable goods. Most states require a sales tax permit.
- You work in a licensed profession. Contractors, cosmetologists, real estate agents, healthcare providers, and tax preparers all need state-issued credentials.
- You run the business from home. Many municipalities require a home occupation permit.
Work through each trigger that applies, in roughly this order.
Registering a Business Name
If your business will operate under any name that doesn’t include your legal last name, file a fictitious business name statement, usually called a DBA (“doing business as”). A dog-walking service called “Happy Paws” needs a DBA. “Jane Smith Dog Walking” probably doesn’t, assuming your name is Jane Smith.
In most states this is handled at the county level through the county clerk’s office, though some states process it through the Secretary of State. The form asks for your legal name, business address, and a description of what the business does. Fees vary by jurisdiction but are generally under $100. Some counties also require you to publish the name in a local newspaper for a set number of weeks, which adds to the cost. Processing can take a few days for online filings or several weeks for paper.
A DBA is not brand protection. It registers the name locally so the public can identify who owns the business. If someone in another county or state uses the same name, your DBA gives you no recourse. Nationwide brand protection requires a federal trademark registration through the U.S. Patent and Trademark Office, which is a separate process.1United States Patent and Trademark Office. How Trademarks and Trade Names Differ
DBAs expire. Renewal periods vary, but five years is common. If yours lapses, you lose the right to operate under the name and may have to refile from scratch.
Getting an EIN
An Employer Identification Number is a nine-digit number the IRS assigns for tax purposes. Sole proprietors aren’t always required to get one. You need an EIN if you hire employees, open a solo retirement plan, or file excise tax returns.2Internal Revenue Service. Get an Employer Identification Number Otherwise your Social Security number works for tax filings.
Many sole proprietors get one anyway. Every time you fill out a W-9 for a client, apply for a business bank account, or submit a vendor application, you’re asked for a tax ID. Using an EIN keeps your Social Security number off documents other people handle. The application is free on the IRS website, takes a few minutes, and the number is issued immediately.2Internal Revenue Service. Get an Employer Identification Number Avoid third-party websites that charge for this. There is never a fee for getting an EIN directly from the IRS.
Licenses, Permits, and Zoning
Whether you need a license depends on your industry and location. Certain professions require state-level licenses issued by regulatory boards: contractors, cosmetologists, real estate agents, healthcare providers, and tax preparers are common examples. These typically involve education requirements, an exam, and continuing education to maintain the credential. Your state licensing board website will list what applies to your trade.
Beyond professional licensing, many cities and counties require a general business license or business tax certificate to operate within their jurisdiction. Fees and renewal schedules vary, so check with your city or county clerk’s office before you start taking on customers.
If you’ll work from home, look into local zoning rules first. Many municipalities require a home occupation permit that limits customer foot traffic, exterior signage, noise, the number of business-related vehicles at the property, and the percentage of your home used for business. Some businesses are prohibited from residential zones outright. The application usually has a fee and sometimes an on-site inspection.
Food preparation, childcare, and anything involving public health face additional permitting from health departments, with separate inspections and fees.
Registering for Sales Tax
If you sell physical goods, most states require you to register for a sales tax permit through the state’s department of revenue or equivalent agency. The permit authorizes you to collect sales tax from customers and obligates you to remit it on a regular schedule, usually monthly or quarterly. Registration is typically free and handled online. Operating without a permit when you should have one exposes you to back taxes, interest, and penalties.
Opening a Business Bank Account
Once you have your DBA certificate (if applicable) and your EIN or Social Security number, open a dedicated business bank account. Most banks ask for your EIN or SSN, your DBA certificate, any relevant business licenses, and a valid photo ID.3U.S. Small Business Administration. Open a Business Bank Account Separating business and personal funds isn’t legally required for a sole proprietorship, but it makes tax time dramatically easier and gives you a clean paper trail if you’re ever audited. Trying to untangle personal and business transactions from a single checking account at the end of the year is a headache worth avoiding.
Taxes You’ll Owe
Nobody withholds anything from your earnings. You’re responsible for calculating and paying both income tax and self-employment tax, and the IRS expects payments throughout the year.
Self-Employment Tax
Self-employment tax covers Social Security and Medicare. The combined rate is 15.3% of your net self-employment earnings: 12.4% for Social Security on earnings up to $184,500 in 2026, and 2.9% for Medicare with no cap.4Social Security Administration. 2026 Cost-of-Living Adjustment (COLA) Fact Sheet If your net earnings exceed $200,000 ($250,000 for married couples filing jointly), you’ll pay an additional 0.9% Medicare surcharge on the amount above that threshold. You can deduct half of your self-employment tax when calculating adjusted gross income, which lowers your income tax bill. That deduction is calculated on Schedule SE and claimed on Schedule 1 of Form 1040.5Internal Revenue Service. Schedule SE (Form 1040), Self-Employment Tax
Quarterly Estimated Payments
The IRS expects quarterly estimated payments if you’ll owe $1,000 or more for the year. For 2026, the deadlines are:
- First quarter: April 15, 2026
- Second quarter: June 15, 2026
- Third quarter: September 15, 2026
- Fourth quarter: January 15, 2027
You can skip the January payment if you file your 2026 return and pay the full balance by February 1, 2027.6Internal Revenue Service. 2026 Form 1040-ES – Estimated Tax for Individuals Missing a deadline triggers an underpayment penalty based on the shortfall, how long it went unpaid, and the quarterly interest rate the IRS publishes. You can avoid the penalty by paying at least 90% of the current year’s tax or 100% of last year’s tax. If your prior-year adjusted gross income exceeded $150,000, the safe harbor rises to 110% of last year’s tax.7Internal Revenue Service. Underpayment of Estimated Tax by Individuals Penalty
Reporting Income and Expenses
All business income and expenses go on Schedule C (Form 1040), which reports your net profit or loss from the business.8Internal Revenue Service. About Schedule C (Form 1040), Profit or Loss from Business (Sole Proprietorship) Deductible expenses include office supplies, software subscriptions, business insurance premiums, vehicle mileage, and a home office deduction if you use part of your home exclusively for business. Your net profit from Schedule C flows into your Form 1040 and is also the starting point for calculating self-employment tax.
Unlimited Personal Liability
The trade-off for the simplicity of a sole proprietorship is unlimited personal liability. Because there’s no legal wall between you and the business, a lawsuit or unpaid business debt can reach your personal bank accounts, your home, and your other assets. A customer who slips in your shop, a vendor you can’t pay, a contract dispute that goes sideways: all of these can reach your personal finances. This is the fundamental difference between a sole proprietorship and an LLC or corporation, where the entity absorbs most of that exposure.
You can’t eliminate the risk without changing structures, but you can manage it. General liability insurance covers third-party claims for bodily injury, property damage, and advertising-related harm. If you provide professional services such as consulting, accounting, or design, professional liability coverage (sometimes called errors and omissions insurance) covers claims that your work was negligent or caused a client financial loss. Neither is legally required in most situations, but the bet gets riskier as your revenue and client list grow.
If You Hire Someone
Bringing on an employee triggers several obligations at once. You’ll need an EIN if you don’t already have one, and you become responsible for:
- Federal payroll withholding: federal income tax, Social Security (6.2%), and Medicare (1.45%) from each employee’s wages, plus the matching employer share of Social Security and Medicare.
- Federal unemployment tax (FUTA): statutory rate of 6.0% on the first $7,000 of each employee’s wages, with a credit of up to 5.4% for employers who pay state unemployment taxes on time, bringing the effective rate to 0.6% and the maximum annual cost to $42 per employee.9U.S. Department of Labor. Unemployment Insurance Tax Topic
- State unemployment insurance: registration with your state’s workforce agency and payments into the state fund. Rates vary by state and claims history.
- Workers’ compensation insurance: required in nearly every state as soon as you hire your first employee. A handful of states require coverage through a state fund; most allow private insurers.
Federal workplace safety standards apply too. With 10 or fewer workers you’re exempt from most OSHA recordkeeping requirements, but you still must report any work-related fatality, in-patient hospitalization, amputation, or loss of an eye.10Occupational Safety and Health Administration. Small Business Safety and Health Handbook The general duty clause applies regardless of size: you’re expected to provide a workplace free from recognized hazards.