Payroll for the Self-Employed: What Actually Applies

Around 4.2 million people work for themselves in the UK, and almost none of them run payroll on their own earnings. A genuinely self-employed sole trader pays income tax and National Insurance through Self Assessment, with the bill due by 31 January each year, not through Pay As You Earn ^[1][2]. Payroll only enters the picture when the self-employed person becomes an employer, or incorporates and starts paying themselves a director's salary.

That distinction trips up a large number of small business owners. The phrase "payroll for the self-employed" usually hides one of three separate situations, and each carries very different obligations to HMRC. Getting them mixed up leads to late registrations, missed filings, and penalties that were entirely avoidable.

This article sets out how a self-employed person actually pays tax, the exact point at which payroll obligations begin, what running payroll involves once that point is reached, and the reliefs and exemptions that apply to the smallest employers. It is written for sole traders, freelancers, and one-person limited companies weighing up their first hire or their own remuneration.

Key takeaways

• A self-employed sole trader does not run payroll on their own income; they report profits and pay Class 2 and Class 4 National Insurance through Self Assessment ^[2][1].
• Payroll becomes mandatory the moment the business takes on an employee earning at or above the Lower Earnings Limit, currently £129 a week for the 2026-27 tax year ^[3].
• An employer must register for PAYE before the first payday, and registration can take up to 5 working days ^[4].
• A director of a one-person limited company is usually an employee of that company and must run PAYE once their salary reaches the Lower Earnings Limit ^[5].
• Employer National Insurance is charged at 15% on earnings above the Secondary Threshold of £96 a week, a cost sole traders never pay on their own drawings ^[3].

Why a sole trader does not run payroll

A sole trader and their business are, in law, the same person. There is no employer and no employee, so there is nothing to run through PAYE. The profit the business makes is the sole trader's income, and it is taxed once, through the annual Self Assessment return ^[1].

PAYE, by contrast, is a system for collecting tax and National Insurance from employees as they are paid, with the employer acting as collector on HMRC's behalf ^[6]. A person cannot be their own employer in an unincorporated business, so the machinery of payroll simply does not apply to their drawings.

How the self-employed actually pay tax and National Insurance

HMRC calculates the self-employed person's liability from the figures on their Self Assessment return, then collects income tax and National Insurance together in a single bill ^[2]. The main payment deadline is 31 January following the end of the tax year, and many sole traders also make payments on account towards the next year's bill ^[1].

Self-employed National Insurance is charged in different classes from employee National Insurance, and the rates differ too. Class 4 is the main charge on profits, while Class 2 protects entitlement to the State Pension and other benefits ^[2]. The table below sets the self-employed position against the employee position so the contrast is clear.

The practical point for a sole trader considering their first hire is that employer National Insurance at 15% is a real, additional cost that never touched their own income ^[3]. Budgeting for it is part of budgeting for the hire itself. For businesses that are outgrowing the sole-trader model and starting to think about staff, dedicated small business payroll is what turns those calculations into compliant payslips.

The three situations where payroll starts

Because the search for "payroll for the self-employed" hides several distinct scenarios, it helps to name them. Each one has a different trigger and a different set of duties.

Situation one: taking on a first employee

The most common route into payroll is hiring. As soon as a sole trader employs someone, the sole trader becomes an employer and inherits the full set of PAYE duties ^[6]. Registration is required before the first payday, and HMRC advises allowing up to 5 working days for the PAYE reference to come through ^[4].

Registration is not always automatic on the very first pound paid. The obligation is triggered by the circumstances of the employee, and the table below lists the main triggers. If any one of them applies, the business must register and operate PAYE ^[4][6].

A sole trader who pays a single casual worker below all of these thresholds may not need a PAYE scheme, but must still keep records of what was paid ^[6]. The safest approach is to check the triggers against each worker before the first payday, because registering late invites a late filing position from the first submission onwards ^[4].

Situation two: incorporating and paying a director's salary

The second route is incorporation. When a sole trader forms a limited company, the legal position changes completely: the company is a separate person, and the owner typically becomes a director and an employee of it ^[5][11]. A director who draws a salary is paid through PAYE like any other employee, so the company must run payroll once that salary reaches the Lower Earnings Limit ^[3].

This is where many newly incorporated owner-managers get caught. They still think of themselves as self-employed, but the company they now run is an employer with PAYE duties. A one-person company that pays its director a salary at or above the Lower Earnings Limit must register for PAYE and file in real time, exactly as a company with staff would ^[6][4].

Directors also have a special National Insurance rule. They are assessed on an annual earnings period even when paid monthly, which changes how contributions build across the year ^[3]. Owner-managers who pay themselves a low salary topped up with dividends need payroll that handles the directors' annual method correctly, or the National Insurance figures will be wrong. A sole-trader and single-person payroll setup that understands the director rule saves a good deal of year-end correction.

Situation three: deemed employment and off-payroll rules

The third situation is subtler. A contractor who works through their own limited company can be caught by the off-payroll working rules, where the client or an agency treats the engagement as deemed employment and deducts tax at source ^[8]. This is not the contractor running payroll on themselves; it is a third party operating PAYE on a deemed payment.

For contractors, the key point is that deemed employment changes who deducts the tax, not the underlying obligation to account for it ^[8]. Anyone working through a personal service company should confirm their status for each engagement, because the answer determines whether tax comes off before they are paid or is settled later through the company's own payroll and returns ^[8]. This area sits close to IR35 and off-payroll working, which deserves its own detailed treatment.

What running payroll actually involves

Once payroll is triggered, the mechanics are the same whether the employer is a former sole trader with one member of staff or a company paying a single director. Each time employees are paid, the employer has to work through a fixed set of tasks ^[5].

The tasks on every payday

Every pay run requires the employer to calculate deductions, produce a payslip, and report the figures to HMRC on or before the day the employee is paid ^[5][6]. The report is a Full Payment Submission, and it must reach HMRC on or before payday so the record stays current ^[6]. The table below lists the recurring steps.

Software that holds the HMRC Recognised badge submits the Full Payment Submission automatically and applies the current rates without manual reconfiguration, which is what keeps a small employer compliant from the first pay run ^[6]. For a business coming from a background of annual Self Assessment, the shift to filing every payday is the single biggest change, and it is where HMRC-recognised payroll software for SMEs does the heavy lifting.

Paying HMRC and meeting deadlines

The deductions collected through payroll are not the employer's money. They are held on HMRC's behalf and paid over by the 22nd of the following tax month for electronic payments, or quarterly where the average monthly liability is small enough to qualify ^[7]. Missing that deadline creates interest and possible penalties on top of the tax ^[7].

Late or missing Full Payment Submissions carry their own consequences. HMRC issues a late filing notice where an employer has paid staff but not filed on time, and can charge a penalty unless there is a valid reason ^[16]. For a first-time employer, building the FPS deadline into the pay-run routine from day one is the simplest way to avoid these notices entirely ^[6].

Reliefs and exemptions for the smallest employers

The tax system offers a few reliefs aimed squarely at small employers, and the newly-hiring sole trader should know which ones apply. The most valuable is Employment Allowance, but it comes with a rule that catches one-person companies.

Employment Allowance and the single-director trap

Employment Allowance lets eligible employers reduce their annual employer National Insurance bill by up to £10,500 for the 2026-27 tax year ^[9]. For a sole trader taking on a first employee, this can wipe out the employer National Insurance cost of that hire entirely, depending on the wage ^[9].

The trap is for companies rather than sole traders. A limited company whose only employee is also its sole director cannot claim Employment Allowance, because the relief is designed to encourage taking on staff, not to subsidise a single owner-director ^[10]. A company becomes eligible once it has a second employee, who is not a director, earning above the Secondary Threshold ^[10]. The table below summarises who can and cannot claim.

Auto-enrolment and the one-person company

Workplace pension duties also scale down for the smallest employers. A one-person limited company where the only worker is the director, with no employment contract, is not treated as an employer for automatic enrolment and does not need to enrol anyone or complete a declaration of compliance ^[13]. The Pensions Regulator sets out this director exemption clearly ^[13].

The moment a second worker is taken on, that exemption can fall away and auto-enrolment assessment begins for eligible staff ^[13]. A sole trader planning to grow beyond a single hire should factor pension contributions and assessment into the cost of the second employee, alongside the employer National Insurance already discussed ^[3]. Accountants managing several small clients typically handle this through a multi-client payroll dashboard that flags each employer's auto-enrolment position automatically.

Choosing how to run payroll once it applies

A sole trader who has become an employer has three broad options: run payroll manually, use payroll software, or outsource to a bureau. Manual payroll using HMRC's free tools is possible but capped and limited, producing no payslips and offering no auto-enrolment assessment, which makes it unsuitable for most growing businesses ^[6].

Payroll software that holds the HMRC Recognised badge is the usual middle path: it calculates deductions, files the Full Payment Submission, and produces compliant payslips without the employer needing to master the underlying tax tables ^[6]. For software platforms and accountants who want to build payroll into their own systems rather than log into a separate tool, an HMRC-recognised payroll API does the compliance calculation behind the scenes. The right choice depends on volume, on whether the business expects to keep growing, and on how much of the process the owner wants to keep in-house.

Work out the true cost of a first hire

Before taking on an employee, an employer can size the real cost with the Moonworkers UK salary calculator. It applies the 2026-27 PAYE and National Insurance rules to any gross salary and returns the employee's take-home pay alongside the employer National Insurance the wage attracts at 15%, the figure a former sole trader needs when budgeting for a first hire.

Conclusion

The label "payroll for the self-employed" is a contradiction for a genuine sole trader, whose income runs through Self Assessment and never through PAYE. Payroll only begins when the self-employed person crosses into being an employer, whether by hiring a first member of staff or by incorporating and drawing a director's salary. The trigger, the registration, and the ongoing filing duties all follow from that crossing, not from self-employment itself.

For a growing business, the shift from an annual tax return to filing on or before every payday is the real change, and it arrives with employer National Insurance, payslip duties, and pension assessment attached. Recognising which of the three situations applies, and setting up compliant payroll before the first payday, turns a source of penalties into a routine that runs itself.

Frequently asked questions

Do self-employed people need to run payroll?

No. A genuinely self-employed sole trader does not run payroll on their own income. They report their profits through Self Assessment and pay income tax and National Insurance in a single bill, usually due by 31 January ^[1][2]. Payroll only becomes necessary if they take on an employee or set up a limited company and pay themselves a director's salary ^[6].

When does a sole trader have to register as an employer?

A sole trader must register for PAYE before the first payday once they employ someone who earns at or above the Lower Earnings Limit, which is £129 a week for the 2026-27 tax year, or who already has another job, receives a pension, or gets taxable benefits ^[3][4]. Registration can take up to 5 working days, so it is worth starting well before the employee's first payday ^[4].

Does a single-director company have to run payroll?

If the director draws a salary at or above the Lower Earnings Limit, the company must register for PAYE and run payroll, because a director is usually an employee of their own company ^[5][4]. Directors are assessed for National Insurance on an annual basis even when paid monthly, so the payroll needs to apply the directors' method correctly ^[3].

Can a one-person company claim Employment Allowance?

No. A limited company whose only employee is also its sole director cannot claim Employment Allowance ^[10]. The relief is meant to support taking on staff, so a company only becomes eligible once it employs a second person, who is not a director, earning above the Secondary Threshold of £5,000 a year ^[9][10].