{ "meta": { "schema": "statbook-api/1", "release_version": "3.0.0", "compiled_at": "2026-09-21T00:00:00Z", "generated_at": "2026-09-28T09:07:46Z", "attribution": [ "© Crown and database right. Derived from content available under the Open Government Licence v3.0 from legislation.gov.uk.", "Contains public sector information licensed under the Open Government Licence v3.0." ], "docs": "https://statbook.co.uk/docs/", "signing": { "scheme": "minisign", "public_key": "RWSPzbJEmAXVEvTqYZ8O9iHuOcOUii5lCNZM5t9bdoQh4ZnwKsxk/+bd", "key_id": "12D5059844B2CD8F", "verify": "https://statbook.co.uk/assurance/#verify" } }, "figure": { "id": "employment.ni.category_letter_matrix", "name": "National Insurance category letters: relief class by letter", "category": "employment", "jurisdiction": "GB", "unit": "ni_relief_class", "value_type": "mapping", "currency": null, "source_type": "administrative", "values": [ { "value": { "entries": [ { "key": "A", "employer_relief": "standard", "employee_class": "standard", "employee_group": "All employees apart from those in groups B, C, H, J, M, V and Z in this table" }, { "key": "B", "employer_relief": "standard", "employee_class": "married_women_reduced", "employee_group": "Married women and widows who have a certificate of election form showing they're entitled to pay reduced National Insurance" }, { "key": "C", "employer_relief": "standard", "employee_class": "over_state_pension_age", "employee_group": "Employees over the State Pension age" }, { "key": "H", "employer_relief": "apprentice_under_25", "employee_class": "standard", "employee_group": "Apprentices under 25" }, { "key": "J", "employer_relief": "standard", "employee_class": "deferred", "employee_group": "Employees who can defer National Insurance because they're already paying it in another job" }, { "key": "M", "employer_relief": "under_21", "employee_class": "standard", "employee_group": "Employees under 21" }, { "key": "V", "employer_relief": "veteran", "employee_class": "standard", "employee_group": "Employees who are working in their first job since leaving the armed forces (veterans)" }, { "key": "Z", "employer_relief": "under_21", "employee_class": "deferred", "employee_group": "Employees under 21 who can defer National Insurance because they're already paying it in another job" }, { "key": "F", "employer_relief": "freeport", "employee_class": "standard", "employee_group": "All employees who work in a special tax site within a Freeport, apart from those in groups I, L, and S in this table" }, { "key": "I", "employer_relief": "freeport", "employee_class": "married_women_reduced", "employee_group": "Married women and widows working in a special tax site within a Freeport who have a certificate of election form showing they're entitled to pay reduced National Insurance" }, { "key": "L", "employer_relief": "freeport", "employee_class": "deferred", "employee_group": "Employees who work in a special tax site within a Freeport and can defer National Insurance because they're already paying it in another job" }, { "key": "S", "employer_relief": "freeport", "employee_class": "over_state_pension_age", "employee_group": "Employees who work in a special tax site within a Freeport and are over the State Pension age" }, { "key": "N", "employer_relief": "investment_zone", "employee_class": "standard", "employee_group": "All employees who work in a special tax site within an Investment Zone, apart from those in groups E, D and K in this table" }, { "key": "E", "employer_relief": "investment_zone", "employee_class": "married_women_reduced", "employee_group": "Married women and widows working in a special tax site within an Investment Zone who have a certificate of election form showing they're entitled to pay reduced National Insurance" }, { "key": "D", "employer_relief": "investment_zone", "employee_class": "deferred", "employee_group": "Employees who work in a special tax site within an Investment Zone and can defer National Insurance because they're already paying it in another job" }, { "key": "K", "employer_relief": "investment_zone", "employee_class": "over_state_pension_age", "employee_group": "Employees who work in a special tax site within an Investment Zone and are over State Pension age" }, { "key": "X", "employer_relief": "no_liability", "employee_class": "no_liability", "employee_group": "employees who do not have to pay National Insurance, for example because they're under 16" } ] }, "value_minor": null, "effective_from": "2026-04-06", "effective_to": null, "announcement_date": null, "enacted_date": null, "instrument_made": true, "terminal_kind": null, "status": "corroborated", "sources": [ { "role": "administering_authority", "citation": "https://www.gov.uk/api/content/national-insurance-rates-letters (HMRC, \"National Insurance rates and categories\", part \"Category letters\": the three \"Category letter / Employee group\" tables — A, B, C, H, J, M, V, Z; Freeport F, I, L, S; Investment Zone N, E, D, K — and the \"Category letter X\" paragraph; the contribution tables in part \"Contribution rates\" list the same sixteen rated letters — every letter but X — \"from 6 April 2026 to 5 April 2027\")", "uri": "https://www.gov.uk/api/content/national-insurance-rates-letters", "retrieved": "2026-09-15T00:16:53Z", "content_hash": "sha256:621f365153fc9ccc3380e8cd8a3131118bcfe01339cfbd05538760e98804ad11" }, { "role": "guidance", "citation": "https://www.gov.uk/guidance/rates-and-thresholds-for-employers-2026-to-2027 (\"Class 1 National Insurance rates\": the employee and employer contribution tables list the same sixteen rated letters, 12 of them with HMRC's own gloss — \"D (Investment Zone - deferment)\", \"E (Investment Zone - married women and widows reduced rate)\", \"F (Freeport)\", \"H (apprentice under 25)\", \"I (Freeport - married women and widows reduced rate)\", \"K (Investment Zone - state pensioner)\", \"L (Freeport - deferment)\", \"M (under 21)\", \"N (Investment Zone)\", \"S (Freeport - state pensioner)\", \"V (veteran)\", \"Z (under 21 - deferment)\" — and letter X, which carries no rate, appears on no rates table)", "uri": "https://www.gov.uk/guidance/rates-and-thresholds-for-employers-2026-to-2027", "retrieved": "2026-07-29T08:16:12Z", "content_hash": "sha256:2b130359261b54fc8f27f3e53cade20f559a6035397c2e3845de72e21ea4eede" } ], "verified": { "administering_authority": "2026-09-15T00:16:53Z", "guidance": "2026-09-21T10:07:35Z" }, "last_verified": "2026-09-15T00:16:53Z" } ], "derivation": null, "invariants": [], "lineage": [], "definitions": [ { "from": null, "to": null, "text": "HMRC's National Insurance category letters and what each one selects. For every letter HMRC prints: the employer-side relief the letter operates — `standard` (the secondary threshold and the secondary percentage); `under_21`, `apprentice_under_25` and `veteran` (a nil secondary rate up to the upper secondary threshold of that name); `freeport` and `investment_zone` (a nil secondary rate up to the special-tax-site upper secondary threshold); `no_liability` — and the employee-side class — `standard` (the main and additional primary percentages above the primary threshold); `married_women_reduced` (the reduced rate under a certificate of election); `deferred` (the additional-rate percentage only, the main rate being paid in another employment); `over_state_pension_age` (no primary contribution); `no_liability` — together with the employee group HMRC prints beside the letter. The letters are HMRC's payroll codes: no Act or instrument prints them. This record holds no threshold and no rate; those stay in the records that own them (employment.ni.class1.*), which a letter's codes select.", "instrument": "HMRC guidance, \"National Insurance rates and categories\" — \"Category letters\" (www.gov.uk/national-insurance-rates-letters); no statutory instrument prints the letters" } ], "applicability": { "basis": "pay_period_start", "note": "The letter an employer operates for an earnings period selects the secondary threshold and the employee rate class applied to that period's earnings. The letter itself has no statutory force; its legal effect is that of the provisions behind the records the codes select — Social Security Contributions and Benefits Act 1992 ss. 6, 8 and 9 (Class 1 liability and the primary and secondary percentages), s. 9A (the age-related secondary percentage, under 21s) and s. 9B (zero-rate secondary contributions for apprentices), and the National Insurance Contributions Act 2022 (freeport and investment-zone tax sites, veterans), whose thresholds are those records' values.", "article": "Social Security Contributions and Benefits Act 1992 ss. 6, 8, 9, 9A, 9B; National Insurance Contributions Act 2022 s. 8 (the upper secondary thresholds the reliefs run to); the letter is HMRC's code, not a provision" }, "scope_note": "A LOOKUP, not a table of numbers: each letter resolves to two codes, and the thresholds and percentages a code names are the existing records (employment.ni.class1.secondary_threshold, .ust, .aust, .veterans_ust, .freeport_ust, .primary_threshold, .employee_main_rate, .employee_additional_rate, .married_women_reduced_rate, .employer_secondary_rate); a second copy of a threshold here would be the drift ADR-0013 §3 forbids. The codes are read from HMRC's own \"Employee group\" description of each letter and checked against the shape of the contribution tables on both pages (letters sharing a code share a rate row). Letter X (no liability, for example under 16s) is stated in prose on HMRC's page and on no rates table. HMRC's page dates its tables for the tax year 6 April 2026 to 5 April 2027 and states no earlier date for the letters; the Freeport letters (2022), the Investment Zone letters (2024) and V (2021) predate it, so this value says which letters are in use from 6 April 2026 and nothing about when each was introduced. No `figure_ref` output yet: a figure_ref must resolve on every entry, and neither an investment-zone upper secondary threshold (refused 2026-09-14, NICA 2022 s. 8 as archived names no investment zone) nor any threshold for X exists to point at. Employees who could carry more than one letter take the one HMRC's guidance directs, which this record does not decide.", "notes": "An administrative table (D23(c)): HMRC is the administering authority and its own guidance page is the A-document, hashed in the receipt and re-read by this script. Every letter is read from the page's \"Category letter / Employee group\" tables (X from its paragraph) and refused if the page's set differs from the script's; each code is refused unless the words it is read from are in that letter's description (\"under 21\", \"Apprentices under 25\", \"(veterans)\", \"special tax site within a Freeport\", \"... within an Investment Zone\", \"Married women and widows\" with \"reduced National Insurance\", \"defer National Insurance\", \"State Pension age\", \"do not have to pay National Insurance\"), `standard` being the absence of every other code's words on that side. The employers' rates-and-thresholds page is the B side: it prints the same sixteen rated letters with HMRC's own bracketed glosses, each checked against the codes, so the value is corroborated; X is on no second page. The value is dated from the sentence the page dates its tables with, and the script refuses when that sentence goes.", "record_version": 3, "key": { "names": [ "category_letter" ], "domain": [ "A", "B", "C", "H", "J", "M", "V", "Z", "F", "I", "L", "S", "N", "E", "D", "K", "X" ] }, "outputs": [ { "name": "employer_relief", "type": "code" }, { "name": "employee_class", "type": "code" }, { "name": "employee_group", "type": "text" } ] }, "receipt": { "record_hash": "sha256:cc19b1cd30409c801d4b4e2ee0f4d850a5ef3d79702549efae14805b12ce55c9", "record_hash_of": "the `figure` object, serialized as UTF-8 JSON with 2-space indent, ensure_ascii=false and a trailing newline", "release_version": "3.0.0", "manifest": "https://statbook.co.uk/v1/releases/3.0.0/manifest.json", "record_url": "https://statbook.co.uk/v1/figures/employment.ni.category_letter_matrix.json", "sources": [ { "role": "administering_authority", "citation": "https://www.gov.uk/api/content/national-insurance-rates-letters (HMRC, \"National Insurance rates and categories\", part \"Category letters\": the three \"Category letter / Employee group\" tables — A, B, C, H, J, M, V, Z; Freeport F, I, L, S; Investment Zone N, E, D, K — and the \"Category letter X\" paragraph; the contribution tables in part \"Contribution rates\" list the same sixteen rated letters — every letter but X — \"from 6 April 2026 to 5 April 2027\")", "uri": "https://www.gov.uk/api/content/national-insurance-rates-letters", "retrieved": "2026-09-15T00:16:53Z", "content_hash": "sha256:621f365153fc9ccc3380e8cd8a3131118bcfe01339cfbd05538760e98804ad11" }, { "role": "guidance", "citation": "https://www.gov.uk/guidance/rates-and-thresholds-for-employers-2026-to-2027 (\"Class 1 National Insurance rates\": the employee and employer contribution tables list the same sixteen rated letters, 12 of them with HMRC's own gloss — \"D (Investment Zone - deferment)\", \"E (Investment Zone - married women and widows reduced rate)\", \"F (Freeport)\", \"H (apprentice under 25)\", \"I (Freeport - married women and widows reduced rate)\", \"K (Investment Zone - state pensioner)\", \"L (Freeport - deferment)\", \"M (under 21)\", \"N (Investment Zone)\", \"S (Freeport - state pensioner)\", \"V (veteran)\", \"Z (under 21 - deferment)\" — and letter X, which carries no rate, appears on no rates table)", "uri": "https://www.gov.uk/guidance/rates-and-thresholds-for-employers-2026-to-2027", "retrieved": "2026-07-29T08:16:12Z", "content_hash": "sha256:2b130359261b54fc8f27f3e53cade20f559a6035397c2e3845de72e21ea4eede" } ], "verified": { "administering_authority": "2026-09-15T00:16:53Z", "guidance": "2026-09-21T10:07:35Z" }, "last_verified": "2026-09-15T00:16:53Z" } }