Sources — official UK data behind every calculator
CalcHub.uk is a YMYL (Your Money, Your Life) reference site. Every number we show — a tax band, a National Insurance threshold, an Ofgem unit rate, an NHS BMI cut-off — is traceable to a named UK government, regulator or statistical authority. This page is our public bibliography. If a figure appears anywhere on CalcHub.uk and you cannot connect it to one of the sources below, that is a bug: please tell us.
Why we publish this: users planning a mortgage, redundancy package or pension drawdown deserve to know exactly where our figures come from. Citing the primary source by URL — rather than a third-party summary — is the only honest way to run a calculator site. It also lets you re-verify any number for yourself in seconds.
How often we verify:every entry below is reviewed at least quarterly (April, July, October, January) and immediately after any UK fiscal event (Spring Budget, Autumn Statement, Scottish Budget, Welsh Budget). When a source publishes a new figure, we update our internal rate files within 24 hours and bump the visible "Last updated" date on every affected page.
Our sourcing principles in plain English:
- Primary sources only — gov.uk, HMRC manuals, the relevant Finance Act on legislation.gov.uk, or the regulator's own website.
- No screenshots of third-party blogs. No "according to" without a link.
- One canonical URL per figure, stored as a comment next to the value in our rate files.
- Historical sources kept alongside current ones, so an archived /uk-tax-rates/2023-24/ page still points to live primary references.
UK Tax & Revenue
Primary HMRC and gov.uk pages used by every Income Tax, NI, CGT, IHT, VAT and Self Assessment calculator on CalcHub.uk. These are the canonical sources we cross-check against on every release.
gov.uk — Income Tax rates and Personal Allowances ↗
Canonical UK Personal Allowance, basic/higher/additional bands and PA taper above £100,000.
HMRC internal manuals (search) ↗
Full HMRC technical manuals used to verify edge-case interpretations (EIM, CG, IHTM, PTM, etc.).
gov.uk — Capital Gains Tax ↗
CGT annual exempt amount, residential vs other rates, reporting deadlines.
gov.uk — Inheritance Tax ↗
IHT nil-rate band, residence nil-rate band, taper threshold and gifts rules.
gov.uk — VAT rates on different goods and services ↗
Standard 20%, reduced 5%, zero-rated and exempt categories.
gov.uk — National Insurance rates and categories ↗
Class 1, 2, 3 and 4 NI thresholds, category letters and employer rates.
gov.uk — Self Assessment tax returns ↗
Filing thresholds, deadlines, payments on account and penalty rules.
HMRC — Estimate your PAYE take-home pay (official tool) ↗
Our primary parity reference for take-home, Income Tax and NI calculators (±£1 tolerance).
Devolved tax (Scotland, Wales, Northern Ireland)
Devolved authorities for region-specific calculators. Scotland and Wales set their own rates for some taxes; Northern Ireland operates Domestic Rates rather than Council Tax.
Revenue Scotland — Land and Buildings Transaction Tax (LBTT) ↗
LBTT bands, Additional Dwelling Supplement (ADS) and first-time buyer relief.
Scottish Government — Income Tax policy ↗
Scottish Income Tax six-band system, current rates and starter/intermediate thresholds.
Welsh Government — Land Transaction Tax guide ↗
LTT bands for residential, higher-rate residential and non-residential property.
Welsh Revenue Authority (Awdurdod Cyllid Cymru) ↗
Operational authority for LTT and Landfill Disposals Tax.
NI Department of Finance — Property rating ↗
Northern Ireland Land & Property Services rating poundage and reliefs.
Property & Mortgage
Sources for Stamp Duty (SDLT/LBTT/LTT), mortgage affordability and Council Tax calculators. Bank of England statistics inform default rate assumptions.
gov.uk — Stamp Duty Land Tax (SDLT) ↗
England & NI residential and non-residential SDLT bands, FTB relief, 3% surcharge.
Bank of England — Statistics ↗
Mortgage approvals, effective rates and Bank Rate decisions used as defaults.
gov.uk — UK House Price Index data downloads ↗
ONS/HMLR joint UKHPI for regional house price context in property calculators.
gov.uk — Check your Council Tax band ↗
Official VOA band lookup, referenced by our Council Tax estimator.
Pensions & Investments
State Pension, ISA, Lifetime ISA and workplace pension calculators draw from these primary sources. HMRC PTM is the canonical technical reference for pension tax.
gov.uk — The State Pension ↗
New and basic State Pension rates, qualifying years and triple-lock uprating.
HMRC — Pensions Tax Manual (PTM) ↗
Annual allowance, lump-sum allowance, MPAA, taper and protected rights detail.
gov.uk — Individual Savings Accounts (ISAs) ↗
Annual ISA allowance, LISA bonus rules, flexible ISA mechanics.
The Pensions Regulator (TPR) ↗
Auto-enrolment minimum contributions, qualifying earnings band.
MoneyHelper (Money & Pensions Service) ↗
Government-backed consumer guidance; we cross-check explanatory text against it.
Employment & Benefits
Minimum wage, statutory pay, Universal Credit and benefits calculators rely on these gov.uk and DWP publications.
gov.uk — National Minimum Wage rates ↗
NMW and National Living Wage rates by age band; apprentice rate.
gov.uk — Statutory Sick Pay (and other statutory pay) ↗
SSP, SMP, SPP, ShPP, SAP weekly rates and eligibility.
gov.uk — Benefits index ↗
DWP top-level directory of UK benefits, eligibility and amounts.
gov.uk — Universal Credit ↗
UC standard allowances, work allowance, taper and elements.
Childcare Choices (HMRC) ↗
Tax-Free Childcare and free hours scheme details for childcare cost calculators.
Energy & Utilities
Energy cost and price-cap calculators use Ofgem as the authoritative source for quarterly default tariff cap values and regional unit rates.
Ofgem — Energy price cap ↗
Quarterly default tariff cap announcements, headline dual-fuel figures.
Ofgem — Energy advice for households ↗
Regional unit rates and standing charges referenced in our cost calculators.
Driving & Transport
VED, fuel duty and ULEZ calculators draw from gov.uk DVLA pages and Transport for London publications.
gov.uk — Vehicle tax rate tables (VED) ↗
VED bands by CO₂ emissions, first-year vs standard rate, expensive-car supplement.
gov.uk — Fuel duty ↗
Excise duty rates on petrol, diesel and alternative fuels.
TfL — Ultra Low Emission Zone (ULEZ) ↗
ULEZ standards, daily charge, exemptions and discounts.
Health & Lifestyle
NHS publications are the authoritative source for our BMI, alcohol units and pregnancy calculators. We follow NHS England guidance verbatim and link back to the relevant page.
NHS — Healthy weight (BMI calculator) ↗
Adult and child BMI ranges with NHS interpretation bands.
NHS — Calculating alcohol units ↗
UK unit definition (8 g pure alcohol) and ≤14 units/week guidance.
NHS — Pregnancy ↗
Due-date methodology (Naegele, ultrasound) and pregnancy week guidance.
Statistics & Data
For inflation, earnings and macroeconomic context we rely on the Office for National Statistics, HMRC published statistics and the UK Statistics Authority for governance.
Office for National Statistics (ONS) ↗
CPI/CPIH, ASHE earnings, population and labour market statistics.
UK Statistics Authority ↗
National Statistics designation and Code of Practice governance.
HMRC published statistics ↗
Receipts, taxpayer populations and policy costings used in commentary.
Standards & Regulators
Regulator pages used to verify definitions (ISA, mortgage, pension), and consumer guidance signposts we include on YMYL pages.
Financial Conduct Authority (FCA) ↗
Regulatory definitions and FCA Handbook references for financial products.
Financial Services Compensation Scheme (FSCS) ↗
Protected deposit and investment limits referenced in savings calculators.
Money and Pensions Service (MaPS) ↗
Parent body of MoneyHelper and Pension Wise — UK statutory money guidance.
Citizens Advice ↗
Independent consumer guidance signposted on benefits and debt-related pages.
How we use these sources inside the codebase
Every numerical input — rate, threshold, allowance — is stored centrally in per-tax-year rate files (for example, src/lib/taxRates/2025-26.ts). Each value is annotated with a comment pointing to the canonical URL in the lists above. No calculator hard-codes a number. When a source publishes a new figure, we update one line in one file and every dependent calculator reflects the change automatically on the next deploy.
For details of our QA process, verification cadence, accuracy targets and corrections policy, see our methodology page.