How to Run Payroll Accurately: A Practical Guide for Small Businesses

Few things damage trust inside a small business faster than getting someone's pay wrong. Yet payroll mistakes are common — and they rarely come from the calculation itself. They come from the inputs: attendance that wasn't recorded, leave that was logged in the wrong place, or an advance someone forgot to deduct.

This guide lays out a simple payroll process you can repeat every period, walks through a worked example, and explains how bringing HR and payroll into one system — with employee self-service — removes most of the risk.

The inputs that cause most payroll mistakes

• Attendance and hours — missing days, late entries or unrecorded overtime.
• Shifts — people paid for the wrong shift pattern.
• Leave — paid and unpaid leave recorded inconsistently.
• Advances and loans — money paid out early that isn't deducted later.
• Expense claims — reimbursements forgotten or paid twice.
• Joiners and leavers — partial months calculated incorrectly.

When each of these lives in a different place — a register, a notebook, a spreadsheet and someone's memory — pulling them together before payday is where errors creep in.

Payroll basics: from gross pay to net pay

Gross pay is everything an employee earns for the period: basic salary plus allowances, overtime or bonuses. Deductions come off that: unpaid absence, advance repayments and any statutory deductions such as income tax withholding or social security contributions. What's left is net pay, the amount that actually reaches the employee.

Here's a worked example with simple numbers, in any currency. Statutory deductions are left out because they depend on your country:

• Basic salary: 50,000
• Housing allowance at 20% of basic: 10,000
• Transport allowance: 5,000
• Gross for a full month: 65,000
• The month has 26 working days and the employee had 2 days of unpaid absence, so they're paid for 24: 65,000 × 24 ÷ 26 = 60,000
• Less advance recovery (the second of three monthly instalments on a 15,000 advance): 5,000
• Net pay before statutory deductions: 55,000

Two things stand out. First, the rule for partial months — working days or calendar days, and which allowances are reduced — is a policy decision, and local labour law may make it for you, so write it down and apply it the same way to everyone. Second, every figure above comes from an input: the salary record, the attendance register, the advance agreement. Get the inputs right and the maths takes care of itself.

A payroll process you can repeat every month

1. Close the period. Agree a cut-off date after which changes roll into the next run.
2. Verify attendance and leave. Confirm the recorded days, shifts and leave for every employee.
3. Apply salary structures. Use consistent, pre-defined structures rather than calculating each salary by hand.
4. Account for advances and claims. Deduct outstanding advances and add approved expense claims.
5. Review before you finalise. Compare totals with last period and investigate anything unusual.
6. Generate payslips. Give every employee a clear record of what they were paid and why.
7. Record the payment. Post the payroll to your accounts so your books stay accurate.

A sample payroll calendar

Putting a date on each step stops payroll turning into a last-minute rush. For a team paid on the 1st of the month, a calendar might look like this:

• 25th: cut-off. Attendance, leave and salary changes after this date roll into next month.
• 26th–27th: managers confirm attendance and decide outstanding leave requests and expense claims.
• 28th: payroll is processed and compared with last month.
• 29th: the owner or finance lead approves it, and it's posted to the accounts.
• 1st: salaries are paid and payslips are available to staff.

Advances, loans and expense claims

Advances cause more payroll disputes than almost anything else, usually because the terms were never written down. Agree the amount and repayment schedule in writing — for example, a 15,000 advance recovered at 5,000 a month over three months — and deduct the instalment in each payroll run until the balance is cleared. Keep a running balance for each employee so either of you can check what's still owed.

Expense claims are different: they reimburse money the employee spent on the business, so they aren't earnings. Approve them against receipts and pay them as a separate line or a separate payment — never fold them into basic pay, or your salary costs will look higher than they are and nobody will know later what the money was for.

Joiners and leavers

Partial months are where calculations most often go wrong. Using the same working-days rule as above, someone who joins with 13 of 26 working days left in the month earns half the monthly gross. For a leaver, prepare a final settlement covering pay up to the last working day, any outstanding advance, and whatever the contract or local law says about unused leave and end-of-service benefits. If you're unsure, check with your accountant or a local adviser before the final payment, not after.

Keep records you can rely on

Every payroll run should leave a clear trail: who was paid, how much, and how each figure was reached. Good records make it easy to answer an employee's question, correct a mistake in the next run, and meet whatever reporting your local regulations require.

In practice that means keeping each employee's salary history, approved leave and attendance, signed advance agreements, a payslip for every run, and the record of when and how each salary was paid. Record salary changes with the date they take effect rather than overwriting the old figure, so you can always explain what someone was paid in any past month.

Employee self-service: let staff help themselves

A surprising amount of HR time goes on answering the same questions: Can I see my last payslip? How much leave do I have left? Employee self-service lets staff view their own payslips, attendance and leave balances whenever they need to, which frees HR for work that actually needs a person.

When you compare employee self-service software, look for these basics:

• Own data only. Each employee sees their own payslips, attendance and leave — never anyone else's.
• Leave requests with approval. Staff submit requests, a manager or HR approves them, and balances update automatically.
• Payslip history, not just the latest month.
• Nothing extra to install. A browser-based system means staff simply sign in with their own login.
• Built into HR and payroll, so staff see the same data payroll uses rather than a copy that drifts out of date.

In ERP Nexl, self-service is part of the HR and payroll software: staff sign in to see their own payslips, attendance and leave balances and to submit leave requests, which HR then approves.

Common payroll mistakes

• Paying from memory. If an adjustment isn't written down before the run, it will be forgotten or applied twice.
• Overwriting salaries. A salary change without an effective date makes past payslips impossible to explain.
• Unrecorded unpaid leave. If it isn't in the system by cut-off day, the employee is paid for days they didn't work, and recovering it later is awkward for everyone.
• Advances with no schedule. An advance without agreed instalments tends to become a gift.
• Paying before reviewing. A quick comparison with last month catches most big errors.
• Payroll that never reaches the books. If salaries are paid but not posted, your profit & loss and cash position are wrong.
• Sharing payslips in group chats. Pay is private; each person should see only their own payslip.

When to move payroll off spreadsheets

• Payroll takes more than a day to prepare each period.
• You've paid someone incorrectly more than once.
• You track attendance or shifts separately from payroll.
• Employees regularly ask HR for payslips or leave balances.
• You need payroll to post into your accounts automatically.

If several of these apply, the rest of your back office may be outgrowing spreadsheets too. Our article on cloud accounting vs spreadsheets covers the accounting side, ERP for small business explains how HR, payroll and accounting fit together, and ERP vs accounting software helps you decide which you need.

Monthly payroll checklist

• Cut-off date set and communicated to managers.
• Joiners, leavers and salary changes entered with effective dates.
• Attendance and leave confirmed for every employee.
• Advance recoveries and approved expense claims checked.
• Payroll processed and compared with last month.
• Payroll approved by someone other than the person who prepared it.
• Payroll posted to the accounts and salaries paid.
• Payslips available to every employee.

Frequently asked questions

What is employee self-service software?

Employee self-service (ESS) software lets staff look up their own HR information — payslips, attendance, leave balances — and submit requests such as leave applications without going through HR. It saves time on routine questions and gives each employee a clear, private record of their pay.

How do I calculate pay for a partial month?

Divide the monthly amount by the working (or calendar) days in the period, then multiply by the days the employee should be paid for. For example, 60,000 a month with 26 working days and 20 days worked gives 60,000 × 20 ÷ 26, or about 46,154. Whichever basis you use, apply it consistently and check it against local law.

Should salary advances go through payroll?

In most cases, yes. Paying the advance separately and recovering it through payroll keeps a clear record of what's been repaid and what's outstanding, and the deduction appears on the payslip, so there's no dispute later.

How long should I keep payroll records?

It depends on your country. Labour and tax laws usually set a minimum retention period, often several years. Keep payslips, salary history, attendance and payment records for at least that long, and ask your accountant what applies to you.

Do I need payroll software for a small team?

Not always. A team of three on fixed salaries can be run from a careful spreadsheet. Software starts to pay off when you track attendance and unpaid leave, give advances, have people joining and leaving, or want payroll posted to your accounts automatically. When comparing costs, check whether a system charges per user or per company — ours is set out on the pricing page.

Payroll tax, social security and statutory deductions vary widely between countries, so confirm the rules that apply to your business with a local adviser.