A payroll system tracks every employee’s hours, calculates what they’re owed, subtracts taxes and other deductions, and delivers the remaining pay to their bank account or paycheck. Whether a company uses spreadsheets or cloud-based software, the core cycle is the same: collect work data, calculate gross pay, withhold the right amounts, pay employees, and report everything to the government on time.
The Basic Payroll Cycle
Every pay period, whether weekly, biweekly, or monthly, follows a repeating sequence of steps. First, employees record the hours they worked, either through a time clock, an online system, or a timesheet approved by a manager. Salaried employees typically don’t track hours unless they earn overtime, but their pay still flows through the same process.
Next, the system calculates gross pay. For hourly workers, that means multiplying hours by their wage rate, including any overtime. For salaried employees, it’s their annual salary divided by the number of pay periods in the year. Bonuses, commissions, and other supplemental pay get added to gross pay during this step.
From that gross amount, the system subtracts mandatory taxes and any voluntary deductions the employee has signed up for. What’s left is net pay, sometimes called take-home pay, and that’s what gets deposited into the employee’s bank account, loaded onto a pay card, or printed as a paper check.
How Gross Pay Becomes Net Pay
The gap between what you earn and what you actually receive comes down to two categories: mandatory withholdings and voluntary deductions.
On the mandatory side, every employee has federal income tax withheld based on the information they provided on Form W-4 when they were hired. That form tells the employer how much to withhold based on filing status, dependents, and any additional withholding the employee requests. Many workers also have state and local income taxes withheld, depending on where they live and work.
Then there are FICA taxes, which fund Social Security and Medicare. The Social Security tax rate is 6.2% of your wages, and the Medicare tax rate is 1.45%. Both are matched dollar for dollar by your employer, so the total going to Social Security and Medicare is actually double what you see on your pay stub. There’s an annual cap on Social Security tax (once your earnings hit that threshold, no more Social Security tax is withheld for the rest of the year), but there’s no cap on Medicare.
Voluntary deductions come next. These include health insurance premiums, contributions to a 401(k) or other retirement plan, life insurance, health savings account contributions, and similar benefits. Many of these are pretax deductions, meaning they’re subtracted from your gross income before taxes are calculated. That lowers your taxable income, so you pay less in taxes. Court-ordered deductions like wage garnishments or child support payments may also be subtracted before the employee receives their pay.
What the Employer Pays Separately
Employees see their half of the equation on their pay stub, but employers carry additional payroll costs that never show up on a worker’s check. Employers pay their own matching 6.2% for Social Security and 1.45% for Medicare on every employee’s wages. That’s a cost on top of what the business pays in salary.
Employers also pay federal unemployment tax, known as FUTA, at a rate of 6.0% on the first $7,000 of each employee’s annual wages. This tax is entirely the employer’s responsibility and is never withheld from an employee’s pay. Most employers receive a credit against FUTA for paying state unemployment taxes, which significantly reduces the effective rate. State unemployment insurance is another employer-paid tax, with rates that vary based on the employer’s industry and claims history.
The IRS treats the taxes withheld from employee paychecks as “trust fund taxes.” The logic is straightforward: that money belongs to the employee and the government, and the employer is simply holding it in trust until it’s deposited with the Treasury. Failing to deposit these funds is one of the most serious payroll violations a business can commit.
Tax Deposits and Filing Deadlines
Employers don’t wait until the end of the year to send withheld taxes to the IRS. They make deposits on a regular schedule, and the frequency depends on the size of the employer’s payroll.
Monthly depositors must send in withheld federal income tax, Social Security, and Medicare taxes by the 15th of the following month. Semi-weekly depositors follow a tighter schedule: taxes on wages paid Wednesday through Friday are due the following Wednesday, and taxes on wages paid Saturday through Tuesday are due the following Friday. If an employer accumulates $100,000 or more in taxes on any single day, the deposit is due the next business day.
Beyond deposits, employers file quarterly and annual returns. Form 941, the quarterly federal tax return, is due by the end of the month after each quarter closes: April 30, July 31, October 31, and January 31. Form 940, the annual FUTA return, is due January 31. Employees must receive their W-2 forms, which summarize their annual wages and withholdings, by January 31 as well. Those same W-2s, along with a transmittal form (W-3), go to the Social Security Administration by the same date.
Missing these deadlines triggers penalties and interest. The IRS takes deposit violations especially seriously because the money was already withheld from workers’ paychecks.
Manual vs. Automated Payroll
Small businesses sometimes start by running payroll manually, using spreadsheets to track hours, look up tax rates, calculate withholdings, and cut checks. The upfront cost is minimal since there’s no software subscription, but the time and risk involved grow quickly. Every calculation depends on a person entering the right numbers, looking up current tax tables, and applying the correct rules. One transposed digit can mean an employee gets the wrong paycheck or a tax deposit comes up short.
Automated payroll software handles these calculations based on rules configured for the business and the jurisdictions where employees work. Tax tables update automatically, so the system applies the correct rates without anyone manually checking for changes. Built-in validation catches discrepancies before paychecks go out, and the software typically handles direct deposit, tax filings, and year-end W-2 generation in one platform. Many payroll tools are part of a broader human capital management suite that connects payroll to time tracking, benefits administration, and HR records.
The tradeoff is cost. Automated systems require a subscription fee, implementation time, and initial configuration. But for most businesses with more than a handful of employees, the reduction in errors, labor hours, and compliance risk makes the investment worthwhile. Manual payroll becomes especially risky when a business operates in multiple states, since each state has its own income tax rules, unemployment tax rates, and filing requirements.
How Employees Fit Into the System
From an employee’s perspective, the payroll system touches your life at a few key moments. When you’re hired, you fill out a W-4 telling your employer how much federal income tax to withhold. Getting this right matters: withhold too little and you’ll owe money at tax time, withhold too much and you’re giving the government an interest-free loan all year.
Each pay period, you should receive a pay stub (either printed or digital) showing your gross pay, each deduction line by line, and your net pay. Reviewing your stub regularly helps you catch errors early, whether it’s a missing hour of overtime or a deduction that doesn’t look right.
At year-end, your employer issues a W-2 by January 31. This form is your official record of what you earned and what was withheld, and you’ll need it to file your tax return. If the numbers on your W-2 don’t match the pay stubs you received throughout the year, that’s a problem worth raising with your employer’s payroll department before you file.
What Happens Behind Each Paycheck
A single payroll run involves more moving parts than most people realize. Before any checks are issued, the employer (or their payroll software) has to verify hours and pay rates, apply the correct federal and state tax withholding based on each employee’s W-4, calculate FICA contributions for both the employee and employer side, subtract pretax benefit deductions, handle any garnishments, compute net pay, initiate direct deposits or print checks, record the journal entries for accounting, and set aside the correct tax deposit amount for the government.
For a business with 50 employees across two states, that’s hundreds of individual calculations every pay period, each one subject to rules that change annually. This is why payroll consistently ranks as one of the most regulated and time-sensitive functions a business performs. Getting it right means employees are paid accurately and on time, tax authorities receive what they’re owed, and the business stays out of trouble.