Self Assessment Documents
What records to keep and gather before you file. Use the checklist to make sure nothing is missed.
Articles
The documents a Self Assessment return is built from
Employment: P60, plus P45 if you changed jobs and P11D if you had benefits. Self-employment: the year's income and expense records, or accounts. Property: rent, expenses, and mortgage interest statements. Investments: dividend vouchers and bank interest summaries. Pensions: contribution statements. Plus Gift Aid donations, student loan status, and Child Benefit amounts if the High Income charge is in play.
Not every filer needs every line — but every line you do need has a document behind it, and the return goes fastest when they arrive together.
The ones people forget
Bank interest — small, spread across accounts, and reportable beyond the personal savings allowance. Dividends from old shareholdings paid by cheque or DRIP. Pension contributions where higher-rate relief must be claimed through the return rather than arriving automatically. Gift Aid, which quietly extends the basic-rate band. And the P11D, which arrives in July and gets filed in a drawer.
Forgetting income risks penalties; forgetting reliefs just donates money. Both are document problems before they are tax problems.
A gathering rhythm that removes January
Everything needed for a return exists by early summer: P60s by 31 May, P11Ds by 6 July, and the year's own records the day it ends. Gather then, file in the autumn at the latest, and the January deadline becomes a payment date only.
One folder — digital counts — per tax year, fed as documents arrive rather than reconstructed under deadline. Our clients skip the gathering entirely: the Evidence Pack inside Compliance Vault™ has collected the year as it happened.
Keep the documents after filing
Retention is part of the obligation: at least 22 months after the tax year end for non-business filers, and five years after the 31 January deadline where self-employment or property income is involved. HMRC can ask for the evidence behind any figure within its enquiry window.
A filed return with no documents behind it is an assertion. The folder is what makes it a fact.
Frequently asked questions
What do I need from my employer for the return?
Your P60 for the year-end position, a P45 if you left a job mid-year, and a P11D if you received benefits in kind. Employers must issue P60s by 31 May and P11Ds by 6 July — chase them if they have not arrived.
I've lost a P60. Can I still file?
Yes. Your employer can reissue the figures, and your HMRC personal tax account shows the pay and tax reported for you under RTI. Use the verified numbers rather than estimates — the data HMRC holds is what your return will be checked against.
Do I need receipts for every expense I claim?
You need records that support every claim — invoices, receipts, or bank evidence, with digital copies fine. Flat-rate claims like approved mileage need the underlying log rather than fuel receipts. If nothing supports a figure, do not claim it.
How long do I keep it all after filing?
At least 22 months after the end of the tax year for employment-and-investment filers; at least five years after the 31 January deadline where self-employment or rental income is involved. In practice: keep the year's folder for six years and never think about it again.