Running payroll for a single employee carries almost the same compliance load as running it for fifty. The employer must still register for PAYE before the first payday, file a Full Payment Submission to HMRC on or before that payday, and operate the same 15% employer National Insurance rate on earnings above the £5,000 Secondary Threshold that applies to any UK business in the 2026-27 tax year [1]. The rules do not scale down with headcount.
This catches out two groups in particular: the sole director of a limited company paying only themselves, and the small business taking on its first member of staff. Both assume that "just one person" means a lighter set of obligations. In practice, the single-employee payroll has its own traps, from director National Insurance calculated over an annual period to the Employment Allowance rule that specifically excludes one-director companies.
This guide sets out the full sequence: registering as an employer, collecting the right starter information, running the pay run under Real Time Information, handling the director and auto-enrolment questions, and paying HMRC. It is written for the employer running payroll for exactly one person, whether that person is a director, a first hire, or a single ongoing employee.
Key takeaways
- Every employer must register for PAYE before the first payday, even a company whose only employee is its sole director.
- Registration can be done up to two months ahead and the PAYE reference can take up to two to three weeks to arrive, so early action matters.
- A Full Payment Submission must reach HMRC on or before payday, regardless of how many employees are on the payroll.
- A company with a single paid director and no other employees cannot claim the Employment Allowance.
- A one-person company consisting only of a single director is never an employer for automatic enrolment, so no workplace pension scheme is required.
Step one: register as an employer
The first legal step is registering with HMRC as an employer, which produces the employer PAYE reference number needed to file. Registration is done through the GOV.UK register-as-an-employer service, and the business must register before the first payday [2]. This is not optional and it is not something a payroll provider can skip.
Timing is the common failure point. An employer can register up to two months before the first payment but no earlier, and HMRC posts the PAYE reference and Accounts Office reference, a process that typically takes up to five working days and sometimes up to two to three weeks [2]. A business that leaves registration until the day before payday risks being unable to file on time.
Directors must register too
A frequent misconception is that a one-person limited company paying only its director sits outside PAYE. It does not. HMRC treats company directors as employees for PAYE purposes, and where a director draws a salary above the National Insurance thresholds or receives taxable benefits, the company must operate PAYE [3]. The obligation applies even when the director is the sole person on the payroll.
The practical implication is that the single-director company has to run a compliant payroll for one person, file RTI, and produce payslips, exactly like any other employer. The convenience of "paying myself" does not remove the reporting duty [4].
Step two: collect the starter information
Before the first pay run, the employer needs a defined set of details for the new employee. GOV.UK requires the employee's full name, date of birth, address and National Insurance number, together with a P45 from a previous employer where one exists [5]. These details drive the tax code and National Insurance category used in the calculation.
Where the employee has no P45, they complete a starter checklist so the employer can work out the correct tax code and whether an emergency code applies [5]. Getting this right at the outset avoids a mid-year tax-code correction, which is one of the more common single-employee payroll headaches.
What the tax code and NI category determine
The tax code sets how much of the employee's pay is free of Income Tax. The standard code for the 2026-27 tax year reflects the £12,570 Personal Allowance, and the National Insurance category letter determines the rate and any relief [6]. For a single employee, confirming these two values correctly is most of the accuracy battle.
The table below summarises the starter information and what each item drives.
| Information needed | Source | What it determines |
|---|---|---|
| Full name, date of birth, address | Employee | Identity and RTI record |
| National Insurance number | Employee or P45 | NI category and record matching |
| P45 or starter checklist | Previous employer or new starter | Tax code, prior pay and tax |
| Bank details | Employee | Payment of net pay |
Step three: run the pay run under RTI
With registration and starter data in place, the recurring task is the pay run itself. Each time the employee is paid, the employer records the pay, calculates Income Tax and National Insurance deductions, works out the employer's National Insurance on earnings above £242 a week, and produces a payslip [7].
The reporting step is Real Time Information. The employer must send a Full Payment Submission reporting pay and deductions to HMRC on or before payday, and an Employer Payment Summary in any month where no one is paid or where statutory recoveries are claimed [8]. There is no small-employer exemption from RTI; a single-employee scheme files exactly like a large one.
Payslips are a legal requirement
Every employee must receive an itemised payslip on or before payday, showing gross pay, the deductions made and net pay [9]. This holds for a single employee just as for a workforce, and it holds for a director paying themselves. A business that needs to produce a one-off compliant document can use an instant payslip generator rather than standing up a full monthly scheme, and an online payslip generator covers the occasional payment.
For an ongoing single-person payroll, HMRC-recognised small business payroll software produces the payslip and files the FPS in the same step, which removes the manual reconciliation that trips up employers doing it by hand. The HMRC Recognised badge is what allows that automatic submission, and it is the baseline any credible tool holds.
Step four: the director and Employment Allowance questions
Two rules apply specifically to the single-employee scenario and both are easy to get wrong: how a director's National Insurance is calculated, and whether the company can claim the Employment Allowance.
Director National Insurance runs on an annual period
Directors do not have their National Insurance worked out pay period by pay period in the ordinary way. HMRC applies an annual earnings period, so a director can earn up to the annual Primary Threshold before employee National Insurance begins, and the liability is assessed across the whole tax year [10]. Two calculation methods exist, the standard annual method and an alternative that reconciles at year-end, but both produce the same total across the year [10].
This matters because a director paid a level salary can see National Insurance appear unevenly through the year under the annual method, which surprises owners expecting a flat monthly deduction. Payroll software configured for directors handles this automatically; a manual calculation is where errors creep in [11].
The single-director Employment Allowance exclusion
The Employment Allowance reduces an eligible employer's secondary Class 1 National Insurance bill each tax year. The catch for single-employee companies is explicit: a limited company cannot claim the allowance if it has just one director and that director is the only employee liable for secondary Class 1 National Insurance [12].
The distinction turns on who the single employee is. A company whose one employee is a non-director paid above the Secondary Threshold can generally claim, while a company whose one employee is the director cannot [13]. The table below sets out the common single-employee cases.
| Company setup | Employment Allowance claimable? |
|---|---|
| Sole director, only employee | No |
| One employee who is not a director, above Secondary Threshold | Yes |
| Director plus one other employee above Secondary Threshold | Yes |
| Self-employed sole trader (no company) | Not applicable |
A company that hires a second person above the threshold part way through the year can become eligible from that point, so the position is not fixed for the whole tax year [12].
Step five: auto-enrolment for a single employee
Workplace pension duties depend on who the single employee is. A one-person company consisting only of a single director is never treated as an employer for automatic enrolment, whether or not that director has a contract, so no pension scheme is required [14].
The exemption narrows once a contract of employment enters the picture. A director is only a worker for auto-enrolment if they have an employment contract and at least one other person in the company also has one, so a company with a director and a single genuine employee under contract does have duties to assess [15].
When the single employee is a first hire
Where the one employee is an ordinary member of staff rather than the director, standard auto-enrolment rules apply. The employer must assess the worker, and an employee who earns above the earnings trigger, is aged between 22 and State Pension age and works in the UK must be enrolled into a qualifying scheme [16]. Getting this assessment into the first pay run avoids a backdated correction later. A growing business often moves from a single hire to a small team quickly, and payroll for SMEs that automates the assessment each period keeps the pension position correct as headcount changes.
Step six: pay HMRC
The final recurring task is paying HMRC what the pay run has calculated: the Income Tax, employee National Insurance and employer National Insurance deducted or due. For most employers this is a monthly payment, due by the 22nd of the following tax month when paid electronically [17].
A single-employee payroll often qualifies for quarterly payment. Where the average monthly liability is expected to be under £1,500, HMRC can allow payment quarterly rather than monthly, with electronic deadlines of 22 July, 22 October, 22 January and 22 April [18]. The reporting duty does not relax: the Full Payment Submission must still be filed on or before each payday even where payments to HMRC are made quarterly [8].
For a sole trader or single-person business weighing whether to run this in-house, payroll for one-person businesses built on a per-payslip model avoids paying a monthly per-employee licence for a payroll that produces one payslip a month. Accountants handling many such micro-schemes typically run them through a multi-client payroll dashboard rather than a separate login per client.
Conclusion
Payroll for one employee is not a lighter version of payroll for many; it is the same compliance machine handling a single record. The employer registers for PAYE, files RTI on or before payday, produces a payslip, and pays HMRC, whether the payroll covers one person or one hundred. The single-employee scenario simply adds its own specific rules: the annual National Insurance period for directors, the Employment Allowance exclusion for one-director companies, and the auto-enrolment exemption that applies until a second contracted worker appears.
The businesses that find this straightforward are the ones that treat the single-employee payroll as a system to be automated rather than a task to be squeezed in manually each month. As more accounting and business tools embed compliant payroll directly, the one-employee pay run is moving from a monthly chore towards a background process, which is where a business owner with one member of staff wants it to sit.
Frequently asked questions
Do I need to register for PAYE if I only employ myself as a director?
Yes. HMRC treats company directors as employees for PAYE purposes, so a company paying its sole director a salary above the National Insurance thresholds, or providing taxable benefits, must register as an employer and operate PAYE. Registration should be completed before the first payday, and because the PAYE reference can take up to two to three weeks to arrive, it is worth registering early.
Can a single-employee company claim the Employment Allowance?
It depends on who the employee is. A limited company with just one director, where that director is the only employee liable for secondary Class 1 National Insurance, cannot claim the Employment Allowance. A company whose single employee is not a director and is paid above the Secondary Threshold can generally claim, and a company that takes on a second qualifying employee part way through the year can become eligible from that point.
Does a sole director need a workplace pension?
No. A one-person company consisting only of a single director is not treated as an employer for automatic enrolment, so it has no duty to set up a workplace pension scheme, whether or not the director has a contract. The position changes only if the company has at least two people who both hold contracts of employment, at which point auto-enrolment duties can apply.
Do I still have to file RTI every month for one employee?
Yes. A Full Payment Submission must be sent to HMRC on or before each payday regardless of headcount, so a single-employee scheme files exactly like a larger one. Even employers permitted to pay HMRC quarterly because their liability is under £1,500 a month must continue to report each pay run through RTI on or before payday.
Image prompt for Imagen (also in frontmatter)
Reportage shot, a UK independent business owner at the counter of a small shop holding a single printed payslip and a calculator, the back of the shop visible behind them with products on wooden shelves, soft natural daylight through a shopfront window, mid-morning, palette of warm white, terracotta, cream, asymmetric composition with the owner in the left two-thirds, shot on a Fujifilm X-T5 at 23mm f/2.8, photojournalism, gentle film grain, no AI artefacts, no warped hands, no warped text, landscape orientation 16:9.
