PAROUSIALimited
Expertise
Case Studies
Our Team
Insights
Contact
Expertise
Case Studies
Our Team
Insights
Contact
  1. Home
  2. Our Expertise
  3. Accountancy & Tax Compliance
  4. Self Assessment
Accountancy & Tax Compliance

Self Assessment
Tax Returns

You must send a Self Assessment tax return if, for example, you were self-employed and earned more than £1,000, were a partner in a business partnership, or had untaxed income such as rent, dividends or foreign income. Online returns, and the tax owed, are due by 31 January after the end of the tax year. We prepare and file personal tax returns for individuals, directors and the self-employed.

Request a ConsultationAll accountancy services

Who this is for

  • Sole traders who earned more than £1,000 from self-employment
  • Partners in a business partnership
  • Landlords, and anyone with untaxed income such as rent, dividends, savings interest or foreign income
  • People with Capital Gains Tax to pay, or a High Income Child Benefit Charge not collected through PAYE
  • Non-UK residents with taxable UK income

How we help

  • Confirm whether you need to file and, if so, register you for Self Assessment
  • Prepare and file your return online, including self-employment, property, dividend and foreign income
  • Explain your bill, including payments on account and the balancing payment
  • Flag when Making Tax Digital for Income Tax will apply to you

What’s included

  • Self Assessment registration where needed
  • Personal tax return prepared and filed online
  • Tax calculation and payment schedule
  • Payments on account reviewed against your expected income

Key dates and figures

Checked against GOV.UK on 24 September 2026. Rates and thresholds change, so confirm how they apply to your own circumstances before acting on them.

Register for Self Assessment

By 5 October 2026 if you are filing for the first time for 2025 to 2026

Source: Check how to register for Self Assessment
Paper return deadline

31 October 2026 for the 2025 to 2026 tax year

Source: Self Assessment tax returns
Online return and payment deadline

31 January 2027 for the 2025 to 2026 tax year

Source: Self Assessment tax returns
Payments on account

31 January and 31 July, each usually half of the previous year’s tax bill

Source: Understand your Self Assessment tax bill: payments on account
Late filing penalty

£100, then £10 a day after 3 months (up to £900), with further penalties at 6 and 12 months

Source: Self Assessment tax returns
Making Tax Digital for Income Tax

Sole traders and landlords: from 6 April 2026 above £50,000 qualifying income, 6 April 2027 above £30,000, 6 April 2028 above £20,000

Source: Find out if and when you need to use Making Tax Digital for Income Tax
Expert Answers

Self Assessment: Frequently Asked Questions

Plain answers to the questions we are asked most often.

Related services

Annual Accounts

Statutory year-end accounts and financial statements for companies, partnerships, and sole traders, prepared for filing at Companies House and HMRC.

Payroll & Bookkeeping

PAYE and Real Time Information payroll, workplace pension administration, and ongoing bookkeeping with management accounts.

Corporation Tax (CT600)

CT600 return preparation and filing, with available reliefs, allowances, and deadlines managed on your behalf.

Related insights

  • HMRC Contacting Sole Traders
  • Set Up Your Tax App with HMRC
  • Paying Tax Arrears Using HMRC Payment Plans

Speak to Our Team

Tell us about your business or your personal tax affairs, and we will explain how we can help.

Request a Consultation

PAROUSIA

Limited

Elite tax advisory and HMRC investigation defence for international families and private capital since 1987.

Strategic Legal & Accounting Partnerships

Expertise

  • Accountancy & Tax Compliance
  • COP 8 Enquiries
  • COP 9 Investigations
  • Criminal Defence
  • Immigration Planning
  • Emigration Services
  • Estate Planning
  • All Expertise

Company

  • Our Team
  • Case Studies
  • Insights
  • Privacy Policy

Contact

  • Airport House, Purley Way
    Croydon CR0 0XZ
    United Kingdom
  • 020 3879 7940
  • PaulaPayen@parousia-accounting.com

© 2026 Parousia Limited. All rights reserved.

Individual regulation under ATT/CIOT and ACCA
Privacy PolicyContact