Fixed-fee Self Assessment · UK-wide online service
Self Assessment Tax Return Online, Done for You by UK Accountants
Fixed-fee Self Assessment tax return service for individuals and businesses across the UK. Qualified accountants prepare and file your SA100 with HMRC from £199 + VAT, agreed before you pay.
- Qualified ICAEW, ACCA and AAT accountants
- Fixed fee, agreed before you pay
- Filed with HMRC before the 31 January deadline
★★★★★ Rated Excellent by clients on Google
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Start My Tax Return
£199 + VAT
One-off fixed fee. No hidden extras.
- SA100 return prepared and filed online
- Employment, self-employed, rental, dividend and investment income
- Tax liability calculated, refund claimed if due
- Allowances and reliefs checked
- Filing confirmation sent to you
Trusted by 270+ businesses
Sole traders, landlords and directors
Qualified accountants
ICAEW, ACCA and AAT qualified team
Fixed fee, no surprises
Agreed up front, paid securely online
Part of Accotax
A trading style of Accotax, accotax.co.uk
Quick answers
What is a Self Assessment tax return?
A Self Assessment tax return (form SA100) is how you tell HMRC about income that is not fully taxed through PAYE, so that the right Income Tax and National Insurance can be worked out. SATR is a UK-wide online service: you order and pay online, send your details securely, and a qualified accountant prepares and files your return.
Who has to file a return?
You usually need to file if you are self-employed with gross income over £1,000, a landlord with rental income over £2,500, a company director with untaxed income, a high earner over £100,000 or £150,000, or you must pay the High Income Child Benefit Charge. See all Self Assessment services.
What are the Self Assessment deadlines?
For the 2025/26 tax year: register by 5 October 2026, paper return by 31 October 2026, online return and any tax owed by 31 January 2027. A late return costs £100 straight away. See the deadline FAQ.
How much does a return cost?
SATR charges a fixed fee from £199 + VAT for a standard employed or self-employed return, agreed before you pay. Rental, company director and complex returns are priced on our pricing page.
Reviewed October 2026 by the qualified accountants at SATR, a trading style of Accotax.
Who we help
Self Assessment services for every kind of taxpayer
Whatever your income looks like, our team prepares an accurate SA100 return, claims every relief you are entitled to and files it with HMRC. Pick the service that fits you, or see all our Self Assessment services.
Sole traders
Business income, expenses and allowances claimed correctly.
Landlords
Rental income, allowable costs and finance cost relief.
Company directors
Salary, dividends and director loan accounts.
Freelancers & contractors
Multiple clients, irregular income, expenses and IR35 points.
High earners
Income over £100,000, child benefit charge and pension relief.
CIS contractors
CIS deductions reclaimed and construction expenses claimed.
Non-resident landlords
UK rental income for landlords living abroad.
Late & overdue returns
File missed returns and deal with HMRC penalties.
How it works
Your tax return done in four simple steps
1
Order online
Choose your package and pay securely online. Your fixed fee is confirmed before we start.
2
Send your details
Complete our short questionnaire and upload your documents. We tell you exactly what we need.
3
We prepare your return
A qualified accountant prepares your SA100, checks reliefs and sends you the figures to approve.
4
We file with HMRC
Once you approve, we file online and send your filing confirmation and tax calculation.
What is included
Everything you need for a complete, compliant return
Every package covers the full Self Assessment process, not just the form. We check your figures, look for legitimate savings and file securely, so your return is right first time.
- SA100 return and supplementary pages prepared and filed online
- Employment, self-employed, rental, dividend, interest and pension income
- Tax and National Insurance calculated, with any refund claimed
- Personal Allowance, Marriage Allowance and expense claims reviewed
- Payments on account explained, with the amounts and dates you need
- Filing confirmation and a copy of your tax calculation (SA302)
- Email and phone support from qualified accountants
Why people choose SATR
- Fixed fee, agreed before you pay
- Qualified ICAEW, ACCA and AAT accountants
- Fully online, no office visits needed
- Part of Accotax, an established accountancy firm
- Reviewed and rated by clients on Google
Fixed-fee pricing
Simple, fixed prices. Pay online and we start straight away
All prices exclude VAT. Your fee is fixed for the whole return, with no hourly billing and no surprise extras.
Standard
£199 + VAT
Employed, self-employed or sole trader income
Employment, self-employment or sole trader income, plus interest and dividends
Landlord
£249 + VAT
Rental property income
Everything in Standard, plus UK property income and allowable expenses
Director & Investor
£299 + VAT
Company directors and investors
Salary, dividends, investments, capital gains on shares and crypto
Complex
From £399
High earners, non-residents, partnerships
High income, foreign income, partnerships and non-resident landlords
Not sure which fits? Get an instant quote or call 0203 4411 258.
Key dates
Self Assessment deadlines for the 2025/26 tax year
5 Oct 2026
Register for Self Assessment
Deadline to tell HMRC you need to file if you are new to Self Assessment.
31 Oct 2026
Paper return deadline
Last day to file a paper SA100 for 2025/26.
31 Jan 2027
Online return and payment
File online and pay any tax due, plus the first payment on account.
31 Jul 2027
Second payment on account
Second instalment towards your 2026/27 tax bill.
Missed a deadline? We can file your late return and help with penalties.
Client reviews
Rated by our clients on Google
Why SATR
A specialist Self Assessment firm backed by Accotax
Specialist focus
We prepare Self Assessment returns every day, so we know the reliefs, the pitfalls and the HMRC rules inside out.
Transparent fixed fees
You see the price before you order. No hourly rates, no surprise invoices after we file.
Fast and fully online
Order, upload and approve from your phone or laptop. Most returns are ready within days of receiving your documents.
Accurate and secure
Every return is checked by a qualified accountant, and your data is handled securely under UK GDPR.
Real people, real support
Speak to an accountant by phone, email or WhatsApp, not a call centre.
Part of Accotax
SATR is a trading style of Accotax, so your tax return sits with an established firm of qualified accountants.
Where we work
Self assessment accountants in London and across the UK
We are based in London and help clients in every part of the UK, fully online. Find your area below or see the full list of locations.
FAQs
Self Assessment tax return questions, answered
Our fixed fees start from £199 + VAT for a standard return. Landlords, directors, investors and more complex returns have their own fixed fee, shown on our pricing page. You always know the fee before you pay.
For the 2025/26 tax year, paper returns were due by 31 October 2026 and online returns are due by 31 January 2027, which is also the deadline to pay any tax owed. Missing it triggers an automatic £100 penalty.
You usually do if you are self-employed, a landlord, a company director, have untaxed income or capital gains, or earn over £100,000. Read our guide on who needs to register for Self Assessment.
Your UTR number, National Insurance number, income and expense records, and details of any other income. After you order, our questionnaire tells you exactly what to upload, so there is no guesswork.
Yes. We file late and overdue returns for previous years and can help you appeal penalties where there is a reasonable excuse. See late Self Assessment returns.
Yes. We can register you with HMRC as self-employed or for Self Assessment and guide you through receiving your UTR. See register for Self Assessment.
We are based in London and work with clients across the UK, entirely online. See all the areas we serve.
Self Assessment Tax Return (SATR) is a trading style of Accotax, a firm of qualified accountants. Visit accotax.co.uk to see our wider accounting services for businesses.
Get your tax return filed, on time and stress-free
Fixed fee from £199 + VAT. Pay online, send your details and let our qualified accountants do the rest.
