What records do I need for Self Assessment?
Get your income, expenses and supporting documents together before your return is prepared.
The HCA knowledge library
Practical guidance for the questions that come up while running a business or managing your tax. Check a deadline, find a form, calculate an estimate or read a short guide with a link to the official source.
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Borrowing, take-home pay, VAT, property tax and practical business planning.
The figures for 2026/27, with income tax, National Insurance, VAT and more in one place.
See which dates apply to you and add a deadline to your own calendar.
Find the current HMRC or Companies House form, download or online filing service for your task.
The latest spring fiscal update, with the relevant official documents and practical context.
Separate the last delivered Budget from the next announcement and track what takes effect when.
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HCA guides
Plain-English starting points, with an official source and a useful next step on every page.
Showing 6 guides
Get your income, expenses and supporting documents together before your return is prepared.
Check when the digital-record and quarterly-update rules may apply to you.
Understand the turnover test and the questions to resolve before you register.
A practical starting list for PAYE, starter information and workplace pensions.
Bring the accounting records together and keep the company’s filing duties in view.
Understand which role you have before registering, verifying or deducting.
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Official tools and references
These links open current GOV.UK guidance. Their content and availability are maintained by the relevant government service.
Go to HMRC’s current and previous tax-year tables.
GOV.UKDatesCheck return, registration and payment dates on GOV.UK.
GOV.UKToolHMRC’s current-year estimate for employees within its stated scope.
GOV.UKFormOfficial starter details where an employee does not have a P45.
GOV.UKNeed an answer for your situation?
A guide can point you in the right direction. Your circumstances decide the right action.