Where the systems diverge
Employed workers have most of their tax and NI deducted at source through PAYE. Self-employed workers file Self Assessment and pay directly. The mechanics are different but the tax rates are broadly comparable — the differences that actually matter are around expenses, NI, and when you pay. This guide covers those differences from a freelancer's practical perspective.
Where the systems diverge
Employed: tax + NI deducted from every payslip via PAYE. Personal allowance applied per pay period. Expenses paid by employer (or reimbursed via P11D). Filing rarely required unless multiple sources.
Self-employed: invoice full amount, receive full amount, then pay tax/NI in January (+ July payments on account). Expenses reduce your own tax. Filing always required.
Both pay income tax at the same rates (20/40/45%). The differences are in the mechanism and the ability to reduce taxable income through expenses.
NI differences worth understanding
Employed NI: Class 1. Employee pays 8% on earnings £242-£967/week; 2% above. Employer also pays 13.8% on top.
Self-employed NI: Class 4 at 6% on profits £12,570-£50,270; 2% above. Class 2 is voluntary from April 2024 for those under £6,725 profit.
Comparable earnings: an employee on £50k pays ~£3,700 Class 1; a self-employed with £50k profit pays ~£2,260 Class 4. Self-employed pays less NI on comparable income — but has fewer benefits (no employer pension, no sick pay, no employer NI contribution).
When you pay: cash-flow implications
Employed: tax + NI on this month's pay leaves your account this month. Zero admin.
Self-employed: collect gross income throughout the year, pay tax/NI months later (31 January following tax year end). Discipline required to hold aside 25-30% for tax.
Combined effect: self-employed effectively gets an interest-free loan from HMRC — the tax owed for April 2025 income sits in your account until January 2026. Provided you don't spend it.
Worked example
**Employed £45,000 gross salary:** Income tax: (£45k - £12,570) × 20% = £6,486. NI Class 1: (£45k - £12,570) × 8% (approx) = £2,594. Take-home: ~£35,920. **Self-employed £45,000 net profit:** Income tax: £6,486 (same as employed). Class 4 NI: (£45k - £12,570) × 6% = £1,946. Take-home: ~£36,568 (Class 4 saves ~£648 vs Class 1). BUT: employed person gets employer NI (~£4,435 paid by employer, not the employee); pension contributions via workplace scheme; sick pay; holiday pay; redundancy protection. The self-employed net is slightly higher on paper but the total 'cost of employment' comparison is more nuanced.
Reference table
| Aspect | Employed | Self-employed |
|---|---|---|
| Income tax rates | 20/40/45% | 20/40/45% (same) |
| NI type | Class 1 (8%/2%) | Class 4 (6%/2%) |
| Personal allowance | £12,570 | £12,570 |
| Payment timing | Monthly via PAYE | January + July |
| Expenses | Employer reimburses | Own claim on SA |
| Pension automatic | Auto-enrolment | Must set up yourself |
| Sick pay | SSP or contractual | None |
| Filing | Only if multiple sources | Every year |
Employment vs freelance decision checklist
- Compare gross-to-net figures using each system's rules
- Add employer NI + workplace pension to the employed total (to see true cost)
- Factor in sick pay / holiday pay value for employment (~10-15% loading)
- Consider expenses you can legitimately claim as freelance (~5-15% of turnover)
- Model tax-year cash-flow with January + July payments if freelance
- Ensure freelance income covers pension savings you'd otherwise get from employer
- Consider IR35 implications if same-client-multiple-year freelance
Slightly less on the same net income due to lower NI (6% Class 4 vs 8% Class 1). But you lose employer NI contributions to your NI record and employer pension contributions. Total picture depends on how much of the 'employer cost' translates back to your freelance rate.
Yes. You file Self Assessment covering both. Employed income uses PAYE tax code; freelance income taxed via SA. Total income determines final bands and payments on account.
No statutory sick pay entitlement. Universal Credit or new-style Employment and Support Allowance may apply. Consider income protection insurance as a self-funded alternative.
Class 2 NI (voluntary from April 2024 if profits below £6,725) is what counts toward state pension. If profits above £6,725, Class 2 is credited automatically. Check your NI record to confirm.
Depends on income variability, autonomy value, benefit needs, and job market. Freelance rate needs to be ~1.5-1.8× your equivalent PAYE salary to net the same after tax, NI, pension, sick-pay buffer, and holidays.
Sources & official references
Related on FreelanceToolkit UK
This guide is general information based on UK rules for the 2025/26 tax year. It is not personal tax or legal advice. For decisions affecting your tax position or legal exposure, consult a qualified accountant or solicitor.