The Home Office guidance stated the following in their guidance for PR applications:

We accept any one of the following, covering the relevant qualifying period:
  • proof of self-assessment with HMRC – such as abbreviated accounts, SA302s and SA100s
  • business accounts
  • P60s, including tax and National Insurance contributions for the relevant period
The same evidence should be provided to establish lawful residence for citizenship applications where relevant.

Alternative/additional evidence of self-employment

If you are not able to send these, you can provide one of the items from each of Categories 1, 2 and 3 below, for each relevant financial year when business was trading.

Category 1: Tax and National Insurance documents

Note: If you wish to use tax and National Insurance documents as evidence, you should only provide one item from any of the groups below to cover each year of your self-employment within your qualifying residence period:

(a) Income Tax documents for each relevant financial year when business was trading:
  • copies or printouts of Self-Assessment tax returns (SA100) for the relevant period and evidence that they have been received by HMRC
  • statements of account (SA300) or tax calculations (SA302) issued by HMRC
  • P60s showing tax and National Insurance paid for each relevant financial year
  • receipts or other written confirmation issued by HMRC of relevant taxes paid
(b) National Insurance documents for each relevant financial year:
  • stamped receipts showing payment of class 2 National Insurance contributions during the relevant period
  • evidence from your/your sponsor’s bank statements showing payment of National Insurance contributions if paid by BACS, CHAPs, online or telephone
  • if you are/were or your sponsor is/was a company director who receives/received wage slips, and these show payment of National Insurance contributions through the PAYE system, all relevant wage slips
  • if you are/were or your sponsor is/was a self-employed subcontractor under the Construction Industry Scheme (CIS), CIS pay and deduction statements showing unique taxpayer reference (UTR) number and CIS deductions for the relevant period
  • certificate of small earnings exception issued by HMRC if you/your sponsor did not earn enough during the relevant tax year to pay National Insurance.
  • any other written confirmation from HMRC of National Insurance paid.
Category 2: Proof of earnings

Please provide one piece of evidence from the list below to cover at least every relevant year of trading:
  • copies of invoices, receipts for payments, etc. – if the business is a limited company, these must be on company-headed paper
  • personal bank statements showing receipt of payments for work carried out
  • business bank statements – you or your sponsor must be named on the account, or otherwise provide evidence to show that you/they have access to the account
  • if trading for more than 12 months, a copy of your/your sponsor’s statutory accounts for the relevant period with a letter from your/their accountant confirming gross/net profit for the relevant period
  • if you have/your sponsor has been a subcontractor under the Construction Industry Scheme, your/their CIS pay and deduction statement, together with one of the above documents
If you are/were or your sponsor is/was a company director who receives/received a salary, please provide one of the following:
  • three payslips for each year within the relevant qualifying period
  • three personal bank statements for each year showing receipt of wages
If you are/were or your sponsor is/was a company director who receives/received dividends, send:
  • dividend vouchers for dividends declared in your/your sponsor’s favour showing the company's and your/your sponsor’s details, with the net dividend amount and tax credit, to cover each year of the relevant qualifying period
  • personal bank statement(s) showing that those dividends were paid into your/your sponsor’s bank account
Category 3: Evidence that the business is/was actively trading

Please provide 2 pieces of evidence from the following list for each relevant year of trading:
  • copies of invoices for services provided
  • contracts to provide services
Category 4: Evidence if the business is a partnership

Please provide one of the following:
  • Certificate of Incorporation with Companies House
  • if you are/your sponsor is the ‘nominated partner’ in the business, a copy or printout of the partnership tax return (SA800) and confirmation that it has been received by HMRC.
Category 5: Evidence if the business is a limited company

Provide one of the following:
  • Certificate of Incorporation with Companies House (certified copy is acceptable)
  • proof that the company is registered with HMRC
  • company tax returns (CT600) (copies or printouts) for each year of the relevant period and evidence of receipt by HMRC (letter or online acknowledgement)
  • appointment report from Companies House (company director only)
  • if the company has been trading for one year or more, a copy of the company annual return (AR01), or a printout of the return if it was sent electronically, together with proof that it has been received by Companies House.
Proof of VAT registration (if applicable)

If, in any relevant tax year, the business turnover exceeded, exceeds, or is expected to exceed, the VAT threshold (£82,000 for 2015/16, £83,000 for 2016/17), please send both:
  • a certificate of VAT registration; and
  • the VAT return for the relevant financial year (a copy or printout) confirming the VAT registration number.