Self Assessment Tax Return Guide 2025/26
Who must file Self Assessment, what to gather before you start, key deadlines for 2025/26 and how to reduce mistakes.
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Long-form guides on Self Assessment, VAT, payroll, accounts, company formation and bookkeeping. Open a guide below when you need a clear overview.
VAT Return Guide for UK Small Businesses
VAT registration, digital records, Making Tax Digital filings, VAT schemes and habits that keep small businesses compliant.
Payroll and PAYE Guide for Employers
PAYE basics, RTI, payslips, pension duties, payroll records and common pitfalls for UK employers.
Limited Company Accounts Checklist
What to assemble before year end: banks, sales, payroll, VAT, director loan, dividends and typical deadline mix-ups.
Landlord Tax Return Guide UK
Rental income, expenses, mortgage interest, repairs vs improvements, joint ownership and company structures.
Corporation Tax Guide for Directors
Taxable profit vs accounts profit, deadlines, CT600 filings, disallowable costs and decisions that shape your bill.
Company Formation Checklist UK
Names, PSCs, share structure, addresses, SIC codes, registrations and bookkeeping from incorporation onward.
Bookkeeping Records Checklist for UK Businesses
Sales and purchase evidence, banks, VAT, payroll, mileage and a simple monthly rhythm to stay audit-ready.
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See FAQsKey Dates
Important UK Tax Deadlines at a Glance
Stay aware of common filing and payment deadlines. For a full list and more detail, use our Tax Calendar.
- Self Assessment31 January
- VAT ReturnsUsually 1 month and 7 days after period end
- Corporation Tax9 months and 1 day after accounting period
- PAYE22nd of each month if paying electronically
Common Questions
Helpful Answers to Common Accounting and Tax Questions
Quick answers to frequently asked questions. For more, visit our full FAQ section.
You usually need to file if you are self-employed, a company director, a landlord receiving rental income, or have other income not fully taxed at source. HMRC may also require you to file if your income is over certain thresholds or if you have been sent a notice to file.
Keep records of sales and income, purchases and expenses, bank statements, receipts, invoices, and any supporting documents. How long you keep them depends on the type of tax and HMRC requirements, typically at least five years for Self Assessment and six years for many business records.
For limited companies, annual accounts are generally due 9 months after the end of the accounting period. The filing deadline at Companies House is usually 9 months after the period end; you may have a later deadline for sending accounts to HMRC with your corporation tax return.
Yes. An accountant can prepare and submit your VAT returns, advise on VAT schemes, and help you stay compliant with HMRC. Many businesses use an accountant for quarterly or annual VAT reporting.
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