Self-Employed National Insurance Calculator (UK 2026/27)
Calculate UK self-employed National Insurance contributions for 2026/27. Includes Class 2 abolition impact, Class 4 rates, and voluntary contribution rules.
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Self-Employed NI Guide 2026/27
What's the key thing to understand about Major Change: Class 2 Abolition?
April 2024 brought a significant change to self-employed NI: Class 2 NI abolished as a compulsory payment for those earning above the Small Profits Threshold (£6,725 for 2026/27). Previously: Class 2 was £3.45/week (£179.40/year) — mandatory if profits over £6,725. From April 2024: above £6,725 profits → no Class 2 owed but still get state pension credit. Below £6,725 profits → can pay Class 2 voluntarily (£3.45/week = £179.40/year) to maintain NI record. Why pay voluntary Class 2 if eligible? Because £179.40/year is far cheaper than losing a qualifying year toward the state pension, which would otherwise cost far more to buy back later or reduce your pension permanently.
What should I know about Class 4 NI Rates 2026/27?
Class 4 NI: paid by self-employed on annual profit. Reduced from April 2024: 6% on profits £12,570-£50,270 (was 9%). 2% on profits above £50,270 (unchanged). Worked examples 2026/27: £25,000 profit: (£25,000 - £12,570) × 6% = £746. £45,000 profit: (£45,000 - £12,570) × 6% = £1,946. £60,000 profit: (£50,270 - £12,570) × 6% + (£60,000 - £50,270) × 2% = £2,262 + £195 = £2,457. £100,000 profit: (£50,270 - £12,570) × 6% + (£100,000 - £50,270) × 2% = £2,262 + £995 = £3,257. Compare with employed: the same profit level as an employee typically incurs more combined employee NI and employer NI than a self-employed person pays in Class 4 alone, which is one of the tax advantages of self-employment.
What should I know about Class 4 Calculation Detail?
Class 4 NI applies to TRADING profits only, not other income. Includes: profit from self-employment trade. Profit share from partnerships. Profit from professional services. Excludes from Class 4: rental income (declared but no Class 4 NI). Capital gains. Dividend income. Investment income. Pension income. Interaction with employed income: if also employed (paying Class 1 NI through PAYE): Class 4 still applies on self-employed profits. No annual cap was removed years ago. Both NI types combine.
What's the key thing to understand about Voluntary Class 2 — When to Pay?
If your profits are BELOW £6,725: Class 2 NOT compulsory. You can pay £179.40/year voluntary Class 2 to maintain state pension qualifying year. Critical for: lower-income years (between paid employment, low-profit early business). Maternity/paternity time. Sabbatical years. Building toward 35 qualifying years (full new state pension). How much one year is 'worth' in state pension: each missing year reduces state pension by £6.32/week (£329/year) over your retirement. Over a 20-year retirement, that's roughly £6,580 in extra state pension for a one-off cost of £179.40 — a strong return that makes voluntary Class 2 worth paying if you have any gap years.