How to Set Up Payroll for a Small Business: Step-by-Step Guide
Why This Matters
Getting payroll right from the start is one of the most important financial decisions a small business owner can make. The IRS and state tax agencies have zero tolerance for errors: late payroll tax deposits carry penalties starting at 2% and escalating to 15% for deposits more than 10 days overdue. Misclassifying an employee as an independent contractor can trigger back taxes, interest, and penalties reaching tens of thousands of dollars per worker. Beyond compliance, employees expect to be paid accurately and on time — payroll errors erode trust and can cost you your best people.
Payroll also involves more than just writing checks. You are responsible for withholding federal and state income taxes, Social Security and Medicare taxes (FICA), filing quarterly and annual tax returns, providing W-2s and 1099s, and complying with state-specific requirements like paid family leave or state disability insurance. Each of these obligations has its own deadline, its own form, and its own penalty structure.
The good news is that modern payroll software has made this dramatically simpler. Tools like Gusto, ADP Run, and QuickBooks Payroll automate most of the compliance work. But you still need to set everything up correctly before running your first payroll. This guide walks you through every step.
Prerequisites / What You'll Need
Before you begin, gather the following:
- Federal Employer Identification Number (EIN) — required to file payroll taxes
- State tax account numbers — for income tax withholding and unemployment insurance
- Employee onboarding documents — W-4, I-9, direct deposit authorization
- Business bank account — payroll is funded from a dedicated account
- Payroll software subscription — Gusto, ADP Run, QuickBooks Payroll, or Rippling
- Pay rate agreements — offer letters or employment contracts confirming compensation
- Benefits information — health insurance premiums, 401(k) elections, FSA contributions
- State-specific requirements — some states require additional forms or registrations
Step 1: Obtain Your EIN and Register with State Tax Agencies
Your Employer Identification Number is your business's tax ID, and you cannot run payroll without one. If you do not have an EIN, apply for one free at IRS.gov — the process takes about 15 minutes and you receive your EIN immediately online.
Next, register with your state's tax agencies. Most states require two separate registrations: one for state income tax withholding and one for state unemployment insurance (SUI). Some states combine these, and a handful have no state income tax (Texas, Florida, Nevada, Wyoming, South Dakota, Washington, Alaska). Visit your state's Department of Revenue and Department of Labor websites to complete registration. Processing times vary from a few days to several weeks, so do this well before you plan to run your first payroll.
If you have employees in multiple states, you need to register in each state where employees work — remote work has made this more complex for small businesses. Some states also require local tax registrations (Pennsylvania cities, New York City, Ohio municipalities). Your payroll software can often flag where you need to register based on employee addresses.
Keep a record of all your tax account numbers. You will need them when setting up payroll software and when filing tax returns.
Step 2: Classify Workers Correctly — W-2 vs. 1099
This is the step most small businesses get wrong, and the consequences are severe. An employee (W-2) is someone you direct and control — you tell them when, where, and how to work. An independent contractor (1099) operates independently, sets their own hours, and typically works for multiple clients.
The IRS uses a multi-factor test to determine worker classification. Relevant factors include: who controls how the work is done, whether the worker can profit or lose money from the engagement, whether the relationship is permanent, and whether the work is a core part of your business. The IRS Form SS-8 can be filed to request an official determination.
Misclassifying a W-2 employee as a 1099 contractor exposes you to back FICA taxes (both the employer and employee portions), back income tax withholding, interest, and steep penalties. Some states have their own tests — California's ABC test is among the strictest and presumes workers are employees unless you can prove otherwise.
For each person working with your business, document your classification decision and the factors supporting it. If there is any doubt, consult an employment attorney or CPA before proceeding.
Step 3: Gather Employee Onboarding Documents
For each new employee, you need three core documents:
Form W-4 (Employee's Withholding Certificate): This tells you how much federal income tax to withhold. The updated W-4 (post-2020) no longer uses allowances — employees simply provide their filing status and any additional withholding adjustments. Your payroll software will use W-4 data to calculate federal withholding automatically.
Form I-9 (Employment Eligibility Verification): Required by federal law to verify that every employee is authorized to work in the United States. You must inspect original documents (passport, driver's license + Social Security card, etc.) within three business days of the employee's start date. Keep completed I-9s on file for at least three years after hire or one year after termination, whichever is later.
Direct Deposit Authorization: Collect each employee's bank routing number and account number. Most employees strongly prefer direct deposit. Your payroll software will handle ACH transfers on payday.
Also collect state tax withholding forms if your state requires them (many states use the federal W-4; others have their own form), emergency contact information, and benefit enrollment elections.
Step 4: Choose Your Payroll Software
Modern payroll software handles tax calculations, filings, and deposits automatically. The right choice depends on your business size, complexity, and budget:
- Gusto — Best overall for small businesses. Full-service payroll with automated tax filings, benefits administration, and a clean interface. Starts around $46/month + $6/employee. Integrates seamlessly with QuickBooks, Xero, and most accounting software.
- ADP Run — Strong compliance support and a large HR library. Better for businesses anticipating rapid growth or needing robust HR features. Pricing is quote-based.
- QuickBooks Payroll — Best if you already use QuickBooks for accounting. Deep integration eliminates manual journal entries. Core plan starts around $50/month + $6/employee.
- Rippling — Best for tech-forward businesses wanting a single platform for payroll, HR, and IT. More expensive but powerful for automation.
- Homebase — Adds hourly employee scheduling and time tracking. Good for restaurants, retail, and service businesses.
When evaluating software, confirm it handles your states' requirements, supports your pay schedule, and offers automated tax deposits and filings (not just calculations).
Step 5: Set Up Pay Schedule and Run First Payroll
Choose a pay frequency: weekly, biweekly (every two weeks), semimonthly (twice a month), or monthly. Biweekly is most common in the US — 26 pay periods per year. Semimonthly (24 pay periods) is popular for salaried employees. Some states have minimum pay frequency requirements, so verify your state's rules.
In your payroll software, enter each employee's:
- Pay rate (hourly or salary)
- Pay schedule
- State and local tax information
- Benefits deductions (health insurance, 401k, HSA)
- Any garnishments or other deductions
Before running your first live payroll, run a test calculation and verify the numbers manually for at least one employee. Check that federal withholding, state withholding, Social Security (6.2%), and Medicare (1.45%) are calculating correctly. Confirm that your bank account has sufficient funds — payroll software typically debits your account 2-4 business days before payday.
Step 6: Set Up Payroll Tax Deposits and Filing Schedule
Federal payroll tax deposits (FICA + withheld income tax) must be deposited electronically via EFTPS (Electronic Federal Tax Payment System). Your deposit schedule depends on your lookback period liability:
- Monthly depositor: Less than $50,000 in taxes during the lookback period — deposit by the 15th of the following month
- Semiweekly depositor: $50,000 or more — deposit within 1-2 days of payroll
State deposit schedules vary by state and liability amount. Your payroll software will calculate deposit amounts and, if you choose full-service payroll, will handle deposits automatically.
Quarterly filings include Form 941 (federal payroll taxes, due April 30, July 31, October 31, January 31) and state equivalents. Annual filings include Form 940 (FUTA unemployment tax) and W-2s distributed to employees by January 31.
Most payroll software files these automatically — verify your software is enrolled in e-file and that your tax agency credentials are correctly configured.
Common Mistakes to Avoid
- Missing state or local registration: Running payroll before obtaining state tax account numbers creates filing gaps that are difficult to fix retroactively
- Misclassifying contractors as employees (or vice versa): Document every classification decision with supporting factors
- Wrong pay frequency: Changing pay schedule after employees have been paid creates prorating headaches and may require state notification
- Not depositing taxes on time: Even one day late triggers penalties. Automate deposits through your payroll software
- Ignoring state-specific requirements: Paid family leave (CA, NY, WA, NJ, MA), state disability insurance, and local taxes vary widely
- Not keeping I-9s on file: ICE audits can occur at any time; missing I-9s carry per-employee fines
- Failing to provide pay stubs: Most states require itemized pay stubs each pay period
Recommended Tools
- Gusto — Full-service payroll, benefits, and HR for small businesses; best-in-class integrations
- Rippling — Unified HR, payroll, and IT platform; ideal for fast-growing teams
- ADP Run — Robust compliance support and HR library for growing businesses
- QuickBooks Payroll — Best for businesses already using QuickBooks for accounting
- Homebase — Scheduling, time tracking, and payroll for hourly workforces
- EFTPS.gov — Free IRS portal for federal tax deposits; required for all employers
Final Tips / Next Steps
Set a recurring calendar reminder for every payroll tax deadline — even if your software automates deposits, you should verify each one completed successfully. Review your state's new hire reporting requirements (most states require reporting within 20 days of hire). As your business grows, revisit your payroll software annually to ensure it still meets your needs. Consider working with a CPA or payroll specialist during your first year to catch any setup issues before they become expensive compliance problems.