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UK National Insurance — Comprehensive

Asked about UK National Insurance Contributions (NIC) for self-employed individuals or employers.

United KingdomTax year 2025· Last reviewed Apr 13, 2026

Key facts — United Kingdom, 2025

Field2024-25 (Prior)2025-26 (Current)2026-27 (Forthcoming)
Class 1 employee main rate8% (from 6 Apr 2024; was 10%)8%8%
Class 1 employee additional rate2% above UEL2%2%
Class 1 employer rate13.8%15%15%
Secondary Threshold (employer)£9,100/yr (£175/wk)£5,000/yr (£96/wk)£5,000/yr
Primary Threshold (employee)£12,570/yr£12,570/yr£12,570/yr
Upper Earnings Limit (UEL)£50,270/yr (£967/wk)£50,270/yr£50,270/yr (frozen to 2027-28)
Employment Allowance£5,000£10,500£10,500
Class 2 statusAbolished (voluntary only)Abolished (voluntary only)Abolished (voluntary only)
Class 2 voluntary weekly rate£3.45£3.50TBC (Autumn 2026)
Small Profits Threshold (SPT)£6,725£6,845TBC
Class 4 main rate6% (from 6 Apr 2024; was 9%)6%6%
Class 4 additional rate2% above UPL2%2%
Class 4 Lower Profits Limit (LPL)£12,570£12,570£12,570
Class 4 Upper Profits Limit (UPL)£50,270£50,270£50,270
CountryUnited Kingdom
Primary LegislationSocial Security Contributions and Benefits Act 1992 (SSCBA 1992); National Insurance Contributions (Reduction in Rates) Act 2024; Autumn Budget 2024 (Class 1 employer changes); Autumn Budget 2025 (no change)
Tax AuthorityHM Revenue & Customs (HMRC)
CurrencyGBP only
ContributorOpen Accountants
Validated byPending -- requires sign-off by a UK-qualified practitioner
Validation datePending

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About

Use this skill whenever asked about UK National Insurance Contributions (NIC) for self-employed individuals or employers. Trigger on phrases like "how much NIC do I pay", "Class 2 contributions", "Class 4 NIC", "Class 1 employer NIC", "Employer NIC 15%", "Secondary Threshold £5,000", "Employment Allowance £10,500", "April 2026 NIC", "Class 2 abolished", "national insurance self-employed", "NIC calculation", "state pension qualifying years", "NIC deferment", "voluntary Class 2", "HMRC NIC payment", or any question about UK NIC obligations. Also trigger when classifying bank statement transactions showing HMRC NIC debits, Self Assessment NIC payments, or Class 2 direct debits. This skill covers Class 1 (employee and employer), Class 2 (voluntary post-April 2024), Class 4 (profit-based), thresholds, payment schedule, bank statement pattern classification, Employment Allowance, interaction with employment Class 1, deferment, state pension entitlement, and edge cases across three tax years (2024-25, 2025-26, 2026-27). ALWAYS read this skill before touching any UK NIC-related work.

United KingdomTax year 2025

Full guide

UK National Insurance -- Comprehensive Skill v3.0

Section 1 -- Quick reference (3-year comparison)

Read this whole section before computing or classifying anything. This skill covers three tax years: the Prior year (2024-25), the Current year (2025-26), and the Forthcoming year (2026-27).

Field2024-25 (Prior)2025-26 (Current)2026-27 (Forthcoming)
Class 1 employee main rate8% (from 6 Apr 2024; was 10%)8%8%
Class 1 employee additional rate2% above UEL2%2%
Class 1 employer rate13.8%15%15%
Secondary Threshold (employer)£9,100/yr (£175/wk)£5,000/yr (£96/wk)£5,000/yr
Primary Threshold (employee)£12,570/yr£12,570/yr£12,570/yr
Upper Earnings Limit (UEL)£50,270/yr (£967/wk)£50,270/yr£50,270/yr (frozen to 2027-28)
Employment Allowance£5,000£10,500£10,500
Class 2 statusAbolished (voluntary only)Abolished (voluntary only)Abolished (voluntary only)
Class 2 voluntary weekly rate£3.45£3.50TBC (Autumn 2026)
Small Profits Threshold (SPT)£6,725£6,845TBC
Class 4 main rate6% (from 6 Apr 2024; was 9%)6%6%
Class 4 additional rate2% above UPL2%2%
Class 4 Lower Profits Limit (LPL)£12,570£12,570£12,570
Class 4 Upper Profits Limit (UPL)£50,270£50,270£50,270
CountryUnited Kingdom
Primary LegislationSocial Security Contributions and Benefits Act 1992 (SSCBA 1992); National Insurance Contributions (Reduction in Rates) Act 2024; Autumn Budget 2024 (Class 1 employer changes); Autumn Budget 2025 (no change)
Tax AuthorityHM Revenue & Customs (HMRC)
CurrencyGBP only
ContributorOpen Accountants
Validated byPending -- requires sign-off by a UK-qualified practitioner
Validation datePending

Conservative defaults:

AmbiguityDefault
Unknown tax yearAsk -- rates differ materially between 2024-25, 2025-26, and 2026-27 (especially employer NIC)
Unknown employment statusAsk -- dual status affects annual maximum cap
Unknown profit levelDo not compute -- profits are required
Unknown whether client wants voluntary Class 2Recommend if profits below SPT and client needs qualifying years
Unknown state pension recordFlag for reviewer
Unknown age (state pension age)Ask -- over state pension age = no Class 4
Unknown payroll size for Employer NICAsk -- Employment Allowance depends on prior-year secondary Class 1 < £100k and connected-company rules

Section 2 -- Required inputs and refusal catalogue

Required inputs

Minimum viable -- tax year, employment status (sole self-employed, employed, employer, or dual), and net self-employment profits (for Class 4) or gross payroll (for Class 1).

Recommended -- bank statements showing HMRC Self Assessment / PAYE payments, prior year SA302 tax calculation, P60/P11D from employment, state pension record printout.

Ideal -- complete SA100/SA103 return data, FPS submissions for PAYE clients, NI record from gov.uk.

Refusal catalogue

R-UK-NIC-1 -- Non-resident or overseas client. Trigger: client is non-UK resident or has complex international arrangements. Message: "NIC for non-resident or overseas clients involves complex rules under EU/bilateral social security agreements. Escalate to a qualified UK practitioner."

R-UK-NIC-2 -- Special categories. Trigger: client is a mariner, share fisherman, volunteer development worker, or religious minister. Message: "Special NIC provisions apply to this category. Escalate to a qualified practitioner."

R-UK-NIC-3 -- Deferment computation. Trigger: client requests Class 1 deferment across multiple employments. Message: "Class 1 deferment requires HMRC application (form CA72A) and case-specific earnings analysis. Flag for reviewer."

R-UK-NIC-4 -- Connected-company Employment Allowance. Trigger: employer is part of a group of connected companies. Message: "Only one company in a connected group can claim the Employment Allowance. Escalate."


Section 3 -- Payment pattern library

This is the deterministic pre-classifier for bank statement transactions related to NIC. When a transaction matches a pattern below, apply the treatment directly.

How to read this table. Match by case-insensitive substring on the counterparty/reference. NIC payments always EXCLUDE from any VAT classification -- they are statutory personal obligations (Class 2/4) or employer payroll obligations (Class 1 employer).

3.1 HMRC Self Assessment payments (include Class 4 + optional Class 2)

PatternTreatmentNotes
HMRC, HM REVENUE, HM REVENUE & CUSTOMSEXCLUDE -- tax/NIC paymentSelf Assessment payments include income tax + Class 4 NIC + voluntary Class 2
HMRC SELF ASSESSMENTEXCLUDE -- SA paymentCombined tax and NIC
HMRC NDDS, HMRC SHIPLEYEXCLUDE -- SA paymentHMRC processing centres
SELF ASSESSMENT, SA PAYMENTEXCLUDE -- SA paymentGeneric SA reference

3.2 Class 2 direct debits (voluntary -- separate from SA)

PatternTreatmentNotes
HMRC NIC, HMRC CLASS 2EXCLUDE -- voluntary Class 2Monthly or quarterly direct debit for Class 2
NATIONAL INSURANCE, NAT INSEXCLUDE -- NIC paymentGeneric NI reference
NIC DIRECT DEBIT, NIC D/DEXCLUDE -- Class 2 DDVoluntary Class 2 via direct debit

3.3 HMRC PAYE payments (includes Class 1 employee + employer)

PatternTreatmentNotes
HMRC PAYE, PAYE NIC, HMRC CUMBERNAULDEXCLUDE -- PAYE paymentCombined PAYE income tax + Class 1 employee + Class 1 employer + Apprenticeship Levy
1025 (followed by UTR)EXCLUDE -- SA paymentHMRC Self Assessment payment reference format (1025 + 10-digit UTR)

3.4 Student loan and other SA components (NOT NIC)

PatternTreatmentNotes
STUDENT LOAN, SLCEXCLUDE -- student loan repaymentNot NIC -- see uk-student-loan-repayment skill
HMRC (large combined payment)EXCLUDE -- combined SAMay include income tax + Class 4 + Class 2 + student loan; cannot split from bank statement alone

3.5 Employer Class 1 (payroll context)

PatternTreatmentNotes
SALARY, WAGES (incoming credit)Not self-employed NICEmployment income -- Class 1 deducted at source by employer
EMPLOYER NICEmployer's Class 1 obligation13.8% (2024-25) or 15% (2025-26 / 2026-27) on earnings above ST

Section 4 -- Worked examples

Example 1 -- Self Assessment balancing payment (combined tax + NIC)

Input line: 31.01.2027 ; HMRC SELF ASSESSMENT ; DEBIT ; SA BALANCING PAYMENT ; -4,200.00 ; GBP

Reasoning: Matches "HMRC SELF ASSESSMENT" (pattern 3.1). This is the 31 January balancing payment for tax year 2025-26. Includes income tax, Class 4 NIC, and possibly Class 2 voluntary. Cannot split NIC from income tax on the bank statement alone. Exclude from VAT. The SA302 tax calculation will show the NIC breakdown.

Classification: EXCLUDE -- SA payment (combined tax and NIC). Request SA302 to determine NIC component.

Example 2 -- Payment on account (31 July)

Input line: 31.07.2026 ; HMRC NDDS ; DEBIT ; PAYMENT ON ACCOUNT ; -2,100.00 ; GBP

Reasoning: Matches "HMRC NDDS" (pattern 3.1). This is the second payment on account for 2025-26, due 31 July 2026. Includes 50% of prior year Class 4 liability and income tax. Exclude from VAT.

Classification: EXCLUDE -- SA payment on account.

Example 3 -- Voluntary Class 2 direct debit

Input line: 15.03.2026 ; HMRC NIC ; DEBIT ; CLASS 2 NIC MAR ; -15.17 ; GBP

Reasoning: Matches "HMRC NIC" (pattern 3.2). Amount approximately £3.50/week x 4.33 weeks = £15.17 monthly. Voluntary Class 2 payment via direct debit. Client has profits below SPT and is paying voluntarily for state pension qualifying years.

Classification: EXCLUDE -- voluntary Class 2 NIC. Not deductible from profits (Class 2 is not a trading expense).

Example 4 -- Employment salary credit (not NIC)

Input line: 28.02.2026 ; ACME LTD SALARY ; CREDIT ; FEB SALARY ; +3,200.00 ; GBP

Reasoning: This is employment income received. Class 1 NIC has already been deducted by the employer at source. This is NOT a self-employment NIC payment.

Classification: NOT NIC -- employment income. Class 1 deducted at source.

Example 5 -- Large SA payment (combined with student loan)

Input line: 31.01.2027 ; HM REVENUE & CUSTOMS ; DEBIT ; SELF ASSESSMENT ; -8,500.00 ; GBP

Reasoning: Matches "HM REVENUE & CUSTOMS" (pattern 3.1). Large SA payment that likely combines income tax + Class 4 NIC + possibly Class 2 + student loan repayment. Cannot split components from bank statement. Need SA302 for breakdown.

Classification: EXCLUDE -- combined SA payment. Request SA302 for NIC/tax/student loan split.

Example 6 -- HMRC refund (overpayment)

Input line: 15.04.2027 ; HMRC ; CREDIT ; SA REPAYMENT ; +650.00 ; GBP

Reasoning: This is a CREDIT from HMRC -- a repayment of overpaid SA (may include overpaid NIC). Exclude from VAT.

Classification: EXCLUDE -- SA refund. Not taxable income. Request SA302 for breakdown.

Example 7 -- Employer NIC impact: 2024-25 vs 2025-26 (side-by-side)

Scenario: A small employer pays one employee a gross salary of £35,000 per year. Show the employer Class 1 NIC cost in 2024-25 (13.8% / ST £9,100) versus 2025-26 (15% / ST £5,000), and net of Employment Allowance.

Component2024-25 (Prior)2025-26 (Current)
Gross salary£35,000.00£35,000.00
Secondary Threshold (ST)£9,100£5,000
Earnings above ST£25,900£30,000
Employer NIC rate13.8%15%
Gross employer NIC£3,574.20£4,500.00
Employment Allowance offset (single-director companies excluded)up to £5,000up to £10,500
Employer NIC after Employment Allowance (if eligible)£0 (£3,574.20 fully absorbed)£0 (£4,500.00 fully absorbed)
Employer NIC if NOT eligible for EA£3,574.20£4,500.00

Real-world impact:

  • For an ineligible employer (e.g. single-director company with no other employees on payroll, or a connected-company group that already claimed elsewhere), the cost rises by £925.80 (+25.9%) for a £35k employee from 2024-25 to 2025-26 -- driven by both the rate increase (13.8% -> 15%) and the ST reduction (£9,100 -> £5,000).
  • For an eligible small employer, the doubled Employment Allowance (£5,000 -> £10,500) absorbs the full increase and may shield additional headcount.
  • Worked check, 2025-26: (£35,000 - £5,000) x 15% = £30,000 x 0.15 = £4,500.00 ✓.
  • Worked check, 2024-25: (£35,000 - £9,100) x 13.8% = £25,900 x 0.138 = £3,574.20 ✓.

Reviewer flag: Confirm Employment Allowance eligibility (employer's secondary Class 1 in the prior tax year was below £100,000, not a single-director-only company, and not the connected company in a group that already claims).

Example 8 -- Self-employed Class 4 across 3 years (same £30,000 profit)

YearProfitsClass 4 calcClass 4 NIC
2024-25£30,000(£30,000 - £12,570) x 6%£1,045.80
2025-26£30,000(£30,000 - £12,570) x 6%£1,045.80
2026-27£30,000(£30,000 - £12,570) x 6%£1,045.80

Class 4 rates and thresholds are unchanged across all three years. Class 2 treated as paid (profits > SPT) in all years -- no voluntary payment needed.


Section 5 -- Tier 1 rules (per year)

Rule 1 -- Class 1 employee formula (all three years -- unchanged)

Class 1 (employee) = max(0, min(earnings, UEL) - PT) x 8% + max(earnings - UEL, 0) x 2%
PT = £12,570/yr, UEL = £50,270/yr (frozen through 2027-28)

Rule 2 -- Class 1 employer formula (rate and threshold CHANGE in 2025-26)

2024-25: Employer NIC = max(0, earnings - £9,100) x 13.8%
2025-26: Employer NIC = max(0, earnings - £5,000) x 15%
2026-27: Employer NIC = max(0, earnings - £5,000) x 15%    (unchanged from 2025-26)

Reduce by Employment Allowance (capped at the lesser of secondary Class 1 due in year and the allowance):

  • 2024-25: up to £5,000
  • 2025-26: up to £10,500
  • 2026-27: up to £10,500

Rule 3 -- Class 2 abolished from 6 April 2024

For all three years (2024-25, 2025-26, 2026-27): self-employed with profits >= SPT are treated as paid automatically (zero-rate credit). No action needed. Profits < SPT: may pay voluntarily (£3.45/wk in 2024-25; £3.50/wk in 2025-26; TBC for 2026-27) to get a qualifying year.

Rule 4 -- Class 4 formula (unchanged across all three years)

Class 4 NIC = (min(profits, £50,270) - £12,570) x 6% + max(profits - £50,270, 0) x 2%

If profits <= £12,570, Class 4 = £0. Rates were reduced from 9% to 6% from 6 April 2024 and have not changed since.

Rule 5 -- Class 4 is based on CURRENT year profits

Unlike Malta SSC, UK Class 4 NIC is calculated on the same year's profits as reported on the SA return.

Rule 6 -- Payment schedule (via Self Assessment)

PaymentDue DateWhat
First payment on account31 January during tax year50% of prior year Class 4 liability
Second payment on account31 July after tax year end50% of prior year Class 4 liability
Balancing payment31 January following tax year endRemaining Class 4 (and Class 2 if voluntary)

Rule 7 -- Employed AND self-employed

Class 1 continues on employment income. Class 4 due on self-employment profits above LPL. Both apply simultaneously. Annual maximum cap checked by HMRC automatically.

Rule 8 -- Over state pension age

No Class 4 liability. No Class 2 needed. Must still file SA return for income tax. Employees over state pension age also stop paying Class 1 employee (but employer Class 1 continues).

Rule 9 -- Multiple self-employments

Profits from all self-employments are aggregated for Class 4.

Rule 10 -- Losses

Zero or negative profits: no Class 4. Voluntary Class 2 may still be paid for state pension.

Rule 11 -- State pension qualifying years

35 qualifying years for full new state pension (£230.25/week in 2025-26). 10 years minimum. Class 2 is the cheapest way to build years (~£182/year vs Class 3 at £923/year).

Rule 12 -- NIC is NOT tax-deductible (personal)

Class 2 and Class 4 NIC are NOT deductible business expenses for the individual. They are personal statutory obligations. Employer Class 1 NIC, by contrast, IS a deductible business expense in the company's accounts.


Section 6 -- Tier 2 catalogue

T2-1 -- Deferment (multiple employments)

Trigger: Client has two employments and expects combined Class 1 to exceed annual maximum. Action: Flag for reviewer. Client may apply on form CA72A to defer Class 1 in secondary employment.

T2-2 -- First year with overlap relief / basis period

Trigger: Client started trading mid-year; basis period allocation unclear under 2024-25 reform. Action: Flag for reviewer to confirm basis period allocation for Class 4.

T2-3 -- Backfilling NI gaps for state pension

Trigger: Client wants to pay voluntary contributions for prior years. Action: Can go back up to 6 years. Class 2 if eligible as self-employed in those years; otherwise Class 3. Flag for reviewer to check NI record.

T2-4 -- Examiners, moderators, foster carers

Trigger: Employment status is ambiguous. Action: Flag for reviewer. Check contract terms for employment vs self-employment.

T2-5 -- Non-resident with UK self-employment

Trigger: Client is non-UK resident but has UK self-employment profits. Action: Escalate -- complex NIC rules for non-residents.

T2-6 -- Employment Allowance eligibility

Trigger: Employer payroll client; need to confirm EA can be claimed. Action: Confirm (a) prior-year secondary Class 1 < £100,000, (b) not a single-director-only company (sole director with no other employees), (c) for a connected-company group, only one company claims. Flag for reviewer if any criterion is uncertain.

T2-7 -- Director on annual earnings basis

Trigger: Director's earnings calculated on cumulative annual basis rather than per pay period. Action: Flag for reviewer -- different rules apply for directors' NIC computation.


Section 7 -- Excel working paper template

UK NATIONAL INSURANCE COMPUTATION -- WORKING PAPER
Client: [name]
Tax Year: [2024-25 / 2025-26 / 2026-27]
Prepared: [date]

INPUT DATA
  Employment status:              [Self-employed only / Employed + self-employed / Employer]
  Net trading profits (SA103):    GBP [____]
  Gross payroll (if employer):    GBP [____]
  Over state pension age:         [YES/NO]
  Voluntary Class 2 elected:      [YES/NO]
  Employment Allowance eligible:  [YES/NO]

CLASS 1 EMPLOYER COMPUTATION (if applicable)
  Year:                           [2024-25 / 2025-26 / 2026-27]
  Secondary Threshold:            [£9,100 / £5,000 / £5,000]
  Rate:                           [13.8% / 15% / 15%]
  Employer NIC:                   GBP [____]
  Less Employment Allowance:      GBP [____] (max £5,000 / £10,500 / £10,500)
  Net Employer NIC:               GBP [____]

CLASS 4 COMPUTATION
  Profits:                        GBP [____]
  Less LPL:                       GBP 12,570
  Main rate band (LPL to UPL):   GBP [____] x 6% = GBP [____]
  Additional rate (above UPL):    GBP [____] x 2% = GBP [____]
  Total Class 4:                  GBP [____]

CLASS 2 (VOLUNTARY)
  Profits vs SPT:                 [Above / Below]
  Treated as paid automatically:  [YES/NO]
  Voluntary payment:              GBP [____]

TOTAL NIC
  Class 1 employer (net of EA):   GBP [____]
  Class 4:                        GBP [____]
  Class 2 voluntary:              GBP [____]
  Total:                          GBP [____]

PAYMENT SCHEDULE
  1st POA (31 Jan during year):   GBP [____]
  2nd POA (31 Jul after year):    GBP [____]
  Balancing (31 Jan after year):  GBP [____]

REVIEWER FLAGS
  [List any Tier 2 flags here]

Section 8 -- Bank statement reading guide

How NIC payments appear on UK bank statements

Self Assessment payments (combined tax + NIC):

  • Description: "HMRC SELF ASSESSMENT", "HM REVENUE & CUSTOMS", "HMRC NDDS", "HMRC SHIPLEY"
  • Timing: 31 January (1st POA + balancing), 31 July (2nd POA)
  • Amount: Combined income tax + Class 4 + optional Class 2 + student loan
  • Cannot split NIC from tax on bank statement -- need SA302

Voluntary Class 2 direct debit:

  • Description: "HMRC NIC", "HMRC CLASS 2", "NIC D/D"
  • Timing: Monthly (around 15th) or quarterly
  • Amount: Approximately £15/month or £45/quarter (£3.45-3.50/week)

Employer PAYE/NIC payments:

  • Description: "HMRC PAYE", "HMRC CUMBERNAULD", "PAYE NIC"
  • Timing: Monthly (around 22nd) or quarterly for small employers
  • Amount: Combined PAYE income tax + Class 1 employee + Class 1 employer + Apprenticeship Levy

HMRC refunds:

  • Description: "HMRC", "SA REPAYMENT"
  • Direction: CREDIT (incoming)
  • May include NIC overpayment component

Key identification tips:

  1. Most self-employed NIC is embedded within SA payments -- you cannot isolate it from the bank statement
  2. Only voluntary Class 2 via direct debit appears as a separate NIC-labelled transaction
  3. The SA302 tax calculation is the authoritative source for the NIC breakdown
  4. Employer NIC is embedded inside the combined monthly PAYE remittance

Section 9 -- Onboarding fallback

If the client provides only a bank statement:

  1. Scan for HMRC debits -- identify all outgoing payments matching Section 3 patterns
  2. Identify SA payment dates -- 31 Jan and 31 Jul payments are SA payments on account
  3. Identify PAYE payment dates -- 22nd of each month for employers
  4. Flag combined nature: "HMRC Self Assessment payments include income tax, Class 4 NIC, optional Class 2, and student loan repayments combined. The bank statement alone cannot isolate the NIC component. Please provide the SA302 tax calculation or the SA100 return for breakdown."
  5. Identify separate Class 2 DD -- small monthly debits (~£15) labelled "HMRC NIC" are voluntary Class 2

Section 10 -- Reference material

Full 3-year rate table

Item2024-252025-262026-27
Class 1 employee main8%8%8%
Class 1 employee additional2%2%2%
Class 1 employer rate13.8%15%15%
Secondary Threshold£9,100£5,000£5,000
Primary Threshold£12,570£12,570£12,570
Upper Earnings Limit£50,270£50,270£50,270
Employment Allowance£5,000£10,500£10,500
Class 2 weekly rate (voluntary)£3.45£3.50TBC
Class 2 annual (voluntary)£179.40£182.00TBC
SPT£6,725£6,845TBC
Class 4 main rate6%6%6%
Class 4 additional rate2%2%2%
LPL£12,570£12,570£12,570
UPL£50,270£50,270£50,270

Test suite

Test 1: 2025-26, self-employed only, profits £30,000. -> Class 4 = £1,045.80. Class 2 treated as paid. Total = £1,045.80.

Test 2: 2025-26, self-employed only, profits £80,000. -> Class 4 = £2,856.60. Total = £2,856.60.

Test 3: 2025-26, profits £10,000. -> Class 4 = £0. Profits > SPT, Class 2 treated as paid. Total = £0.

Test 4: 2025-26, profits £5,000, voluntary Class 2. -> Class 4 = £0. Class 2 = £182.00. Total = £182.00.

Test 5: 2025-26, profits -£3,000, voluntary Class 2. -> Class 4 = £0. Class 2 = £182.00. Total = £182.00.

Test 6: 2025-26, employed (£45,000 salary, Class 1 via payroll) + self-employed profits £20,000. -> Class 4 = £445.80. Annual max checked by HMRC.

Test 7: 2025-26, age 69, profits £40,000. -> Class 4 = £0 (over state pension age). Total = £0.

Test 8: 2024-25, profits £30,000. -> Class 4 = £1,045.80. Class 2 treated as paid (profits > SPT £6,725).

Test 9: 2024-25, employer, employee salary £35,000, EA-ineligible. -> Employer NIC = (£35,000 - £9,100) x 13.8% = £3,574.20.

Test 10: 2025-26, employer, employee salary £35,000, EA-ineligible. -> Employer NIC = (£35,000 - £5,000) x 15% = £4,500.00. Year-on-year increase: £925.80 (+25.9%).

Test 11: 2026-27, employer, employee salary £35,000, EA-ineligible. -> Employer NIC = (£35,000 - £5,000) x 15% = £4,500.00 (unchanged from 2025-26).

Test 12: 2025-26, employer, two employees £25k + £25k, EA-eligible. -> Gross employer NIC = 2 x (£25,000 - £5,000) x 15% = £6,000. After EA (£10,500): £0 employer NIC payable.

Prohibitions

  • NEVER compute NIC without confirming the tax year (Class 1 employer rates and ST changed significantly in April 2025)
  • NEVER tell a client they must pay Class 2 -- it is voluntary since 6 April 2024
  • NEVER tell a client with profits below SPT that they automatically get a qualifying year
  • NEVER apply Class 4 rates to employment income
  • NEVER ignore the annual maximum NIC cap for dual-status clients
  • NEVER advise on deferment without confirming all employment income sources
  • NEVER present NIC figures as definitive for dual-status clients
  • NEVER assume Class 2 is treated as paid for clients with profits below SPT
  • NEVER advise on NIC for non-resident clients without escalating
  • NEVER apply 13.8% / £9,100 to 2025-26 or 2026-27 employer payroll (rate is 15% / £5,000)
  • NEVER apply the £5,000 Employment Allowance to 2025-26 or 2026-27 (it doubled to £10,500)
  • NEVER allow Employment Allowance for a single-director-only company or for more than one company in a connected group

Disclaimer

This skill and its outputs are provided for informational and computational purposes only and do not constitute tax, legal, or financial advice. Open Accountants and its contributors accept no liability for any errors, omissions, or outcomes arising from the use of this skill. All outputs must be reviewed and signed off by a qualified professional (such as a CPA, EA, tax attorney, or equivalent licensed practitioner in your jurisdiction) before filing or acting upon.

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