Authoritative Tax & Compliance Intelligence

UK Tax Knowledge Base & HMRC Filing Hub

Statutory guidance on HMRC reporting forms, tax allowances, filing obligations, and statutory deadlines for businesses, contractors, sole traders, and landlords. Fully aligned with current legislation and MTD reforms.

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Showing 30 authoritative guidance articles
CIS & BuildersCIS Gross (0%)HMRC Verified

CIS Gross Payment Status (0%): Statutory Qualification & Audit Guide

Statutory rules for UK CIS Gross Payment Status under Schedule 11 Finance Act 2004: Turnover test, Compliance test, annual TTQR audit, and cancellation risks.

Updated Sep 2026Read Guide →
CIS & BuildersCIS300HMRC Verified

HMRC Form CIS300: Construction Industry Scheme & Monthly Returns Guide

Statutory rules for UK Construction Industry Scheme on Form CIS300, 20% and 30% deduction rates, verification rules, monthly deadlines, and penalties.

Updated Sep 2026Read Guide →
CIS & BuildersVAT DRC / CISHMRC Verified

VAT Domestic Reverse Charge for Construction Services: Builder Guide

Statutory rules for UK VAT Domestic Reverse Charge (DRC) under VATA 1994 s55A, mandatory invoice wording, end-user exemptions, and cash flow impact.

Updated Sep 2026Read Guide →
Accounting & Books

Bank & Payments: How Reconciliation Stays Reconciled

Bank reconciliation in ac-co: how bank feed evidence is treated, why a bank line links to only one journal entry, and what a reconciliation sign-off preserves.

Updated Sep 2026Read Guide →
Accounting & Books

Chart of Accounts: Structure, Not Just a List of Names

A chart of accounts for a UK small business needs a hierarchy: what a leaf account is, and how ac-co protects the accounts your own reports depend on.

Updated Sep 2026Read Guide →
Accounting & Books

Counterparties & Products: Customer and Supplier Records

Customer and supplier records that stay clean, and how catalog items connect to your chart of accounts — the third domain of the Ideal Ledger standard.

Updated Sep 2026Read Guide →
Accounting & Books

The Ideal Ledger: ac-co's Open Bookkeeping Standard

The published rules ac-co's ledger is built to: nine bookkeeping principles covering immutability, reversal, bitemporal history, VAT, FX and period locks.

Updated Sep 2026Read Guide →
Accounting & Books

Invoices & Bills: What Happens When You Issue One

What happens when you issue an invoice: how numbering works, what issuing locks down, and why a credit note — not a delete — is the way to undo one.

Updated Sep 2026Read Guide →
Accounting & Books

Journal Entries & Posting: What a Journal Entry Is

What a journal entry (posting) actually is, why it has to balance, and what happens once it is posted — the first domain of ac-co's Ideal Ledger standard.

Updated Sep 2026Read Guide →
Accounting & Books

VAT, FX & Reports: The VAT Control Account Explained

The VAT control account explained: how foreign currency is translated and split into realised and unrealised gains, and why every report reads the same numbers.

Updated Sep 2026Read Guide →
Corporation TaxHMRC Verified

Corporation Tax Deadlines & Accounting Periods: Statutory Guide

Statutory rules for UK Corporation Tax deadlines: 9 months 1 day payment rule, 12-month CT600 filing deadline, accounting period rules, and late filing penalties.

Updated Sep 2026Read Guide →
Corporation TaxCT600HMRC Verified

HMRC Form CT600: Corporation Tax Rates, Marginal Relief & Filing Guide

Statutory rules for UK Corporation Tax on Form CT600: 19% small profits rate, 25% main rate, Marginal Relief calculation, and associated companies rules.

Updated Sep 2026Read Guide →
PayrollP60/P45/P11DHMRC Verified

UK Payroll & RTI Compliance: Forms P45, P60, P11D & FPS Submissions

Statutory rules for UK PAYE Real Time Information (RTI), 'on or before' FPS deadlines, EPS offsets, and employee statutory forms P45, P60, and P11D.

Updated Sep 2026Read Guide →
LandlordsSA105HMRC Verified

Buy-to-Let Rental Accounts & Expenses: Statutory Landlord Guide

Statutory rules for UK landlord property accounting, allowable rental expenses matrix, joint ownership Form 17 declarations, and MTD landlord compliance.

Updated Sep 2026Read Guide →
LandlordsEICR / CP12 / EPCHMRC Verified

Landlord Compliance Certificates: EICR, CP12 Gas Safety & EPC Guide

Statutory safety certificates for UK landlords: EICR electrical rules, CP12 gas safety, EPC energy ratings, £30,000 penalty risks, and Section 21 validity.

Updated Sep 2026Read Guide →
LandlordsNRL1HMRC Verified

Non-Resident Landlord Scheme (NRL1): Statutory Tax Withholding Guide

Statutory rules for UK non-resident landlords under Form NRL1, the mandatory 20% letting agent withholding tax, quarterly returns, and gross payment approval.

Updated Sep 2026Read Guide →
ElectriciansSA100 / SA103 / VAT100 / CIS300HMRC Verified

Sole Trader Electrician Tax & Accounting: Tools, Vans, CIS & VAT Guide

Tax and accounting guide for UK electricians: Annual Investment Allowance on test tools, commercial van tax write-offs, CIS refunds, and VAT Reverse Charge rules.

Updated Sep 2026Read Guide →
ElectriciansEICR / EIC / MEIWC / PATHMRC Verified

Electrician Statutory Certificates: EICR, EIC, MEIWC & PAT Guide

Statutory guide to electrical certificates in the UK: EICR, EIC, MEIWC, PAT testing, BS 7671 18th Edition, Part P Building Regs, and electrician legal liability.

Updated Sep 2026Read Guide →
VATHMRC Verified

UK VAT Registration Guide: £90,000 Thresholds, Rules & Deadlines

Statutory rules for UK VAT registration under VATA 1994, the £90,000 threshold, rolling 12-month test, 30-day forward test, and voluntary registration.

Updated Sep 2026Read Guide →
VATHMRC Verified

UK VAT Accounting Schemes: Standard vs Cash vs Flat Rate Guide

Statutory rules for UK VAT schemes under VATA 1994: Standard accruals, Cash Accounting (£1.35m threshold), Flat Rate Scheme (£150k), and limited cost trader rules.

Updated Sep 2026Read Guide →
VATVAT100HMRC Verified

HMRC Form VAT100: MTD VAT Return Process & Penalty Guide

Statutory rules for UK VAT returns on Form VAT100 via Making Tax Digital, 9-box return mechanics, digital links, deadlines, and points-based penalties.

Updated Sep 2026Read Guide →
Self Assessment

Self Assessment Deadline 2025/26: Every Date You Need to Know

The full Self Assessment calendar for the 2025/26 tax year — registration, paper and online filing, and both payment dates, each sourced to gov.uk.

Updated Sep 2026Read Guide →
Self AssessmentHMRC Verified

MTD for ITSA 2026/27: Statutory Thresholds, Quarterly Deadlines & Rules

The complete statutory guide to Making Tax Digital for Income Tax Self Assessment: April 2026 £50k thresholds, quarterly updates, and digital record obligations.

Updated Sep 2026Read Guide →
Self Assessment

Self Assessment Late Filing Penalty: The Full Scale

What HMRC charges for a late Self Assessment return or payment, what counts as a reasonable excuse, and how to appeal — every figure linked to gov.uk.

Updated Sep 2026Read Guide →
Self AssessmentSA100HMRC Verified

HMRC Form SA100: Statutory Filing Rules, Obligations & Criteria

Who must submit HMRC Form SA100, statutory self-assessment criteria, filing routes, key deadlines, and penalty regimes under the Taxes Management Act 1970.

Updated Sep 2026Read Guide →
Self AssessmentSA103HMRC Verified

HMRC Form SA103: Sole Trader & Self-Employed Tax Return Guide

Statutory rules for sole trader self-employment accounting, default cash basis from 2024/25, £1,000 trading allowance, allowable expense rules, and SA103 submission.

Updated Sep 2026Read Guide →
Self AssessmentSA105HMRC Verified

HMRC Form SA105: UK Property Income & Section 24 Landlord Guide

Statutory rules for UK residential landlords, Section 24 mortgage interest relief restrictions, repair vs capital distinctions, and SA105 tax return filing.

Updated Sep 2026Read Guide →
Self AssessmentSA108HMRC Verified

HMRC Form SA108: Capital Gains Tax, Crypto Assets & Property Guide

Statutory rules for UK Capital Gains Tax on Form SA108, the reduced £3,000 exemption, Section 104 crypto pooling, and 60-day residential property rules.

Updated Sep 2026Read Guide →
Self Assessment

How to Get Your SA302 from HMRC

What an SA302 is, why mortgage lenders ask for one, and the two ways to get yours from HMRC: through your personal tax account or your filing software.

Updated Sep 2026Read Guide →
Self Assessment

How to Find Your UTR Number

What a UTR is, where to find one you've already got, how long a new one takes to arrive, and what to do if HMRC hasn't sent you one at all.

Updated Sep 2026Read Guide →