Rated 5.0 on Google One fixed monthly fee, agreed in writing FreeAgent or Xero included Brixton, by appointment Looking after South London businesses since 2015

Accountants in South London Who takes every deadline off your desk?

Accountants in South London for small limited companies, freelancers and contractors. One fixed monthly fee, agreed in writing, covers accounts, tax returns, VAT and payroll, and one of our two accountants, the person doing your work, answers the phone.

Accountants in South London taking deadlines off your desk for one fixed monthly fee, agreed in writing.

  • Small companies, freelancers, contractors
  • Fixed fee agreed in writing
  • Software included and set up
  • Brixton since 2015, by appointment

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A few quick questions, then a plain recommendation and a fixed monthly fee in writing. About two minutes. No monthly tie in.

Accountants in South London: Colourfully painted exterior of Coldharbour Works on Coldharbour Lane
Our Brixton office
5.0 Rated 5.0 on Google Read the reviews

What stays with you

Raise your invoices and keep your receipts in FreeAgent or Xero. Answer us when we ask about something.

What moves to us

We handle payroll, VAT returns, year-end accounts, corporation tax, the confirmation statement and your own tax return before each date.

What clients say about us

These reviews are shown word for word from Google, where One Abacus is rated 5.0.

Read them on Google
One Abacus was recommended to me by several friends and I truly owe them a huge favour as this company has been exemplary! As a new limited company myself and a novice to the contracting world I have had tons of questions and they have been dealt with promptly, effectively and in an approachable and really helpful manner. I couldn't recommend One Abacus enough!
Molly Eve StevensGoogle review
I am currently using one Abacus for sorting out all my freelance accounts and i have to say everything has been perfect with my accountant. they are normally always available even on the weekends when you need something sorted out really quickly. they have sorting out everything from helping with mortgage and notifying when you to pay your tax. really nice and responsive people to talk to if you have questions.
Dean AdjeikumGoogle review
One Abacus has provided me a comprehensive service, very professional accountant, but friendly at the same time, maximum availability, I couldn't be happier.
Giulia CGoogle review

Your company’s dates, and who deals with them

See what each deadline involves when you handle it alone. Then switch views to see what moves to One Abacus.

  1. 22ndevery month

    Payroll and PAYE

    Payslips, the submission to HMRC and the PAYE payment for you and anyone you employ.

  2. 1m 7dafter each VAT quarter

    VAT return

    Prepared from your books and filed under Making Tax Digital, with the VAT kept apart from what is yours.

  3. 9mafter your year end

    Year-end accounts

    Filed with Companies House on time, built from books that are already up to date.

  4. 9m 1dafter your year end

    Corporation tax

    Worked out well before it is due and planned for during the year, with the return filed alongside.

  5. 14dafter your review date

    Confirmation statement

    The yearly check of your company details at Companies House.

  6. 31 Janevery year

    Your self assessment

    Your own return as a director or freelancer, with any payment on account explained before it lands.

  7. Youevery week

    One job stays with you

    You raise invoices, keep receipts in the software and answer when we need to check something.

On your own, all six jobs land on you, along with learning the rules and remembering every date.

With us, all six move across while you keep invoicing, saving receipts and answering the occasional question.

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What changed when we stepped in

These are real client stories, told without names.

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PainterWhose work started selling

The work grew before the paperwork did

Her paintings started selling far better than expected, and she was worried about tax and VAT. The position was less bad than she feared, but it needed steering. We moved her from an accidental sole trade into a limited company, handled the registrations and showed her the software routine.

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8 US citiesWhere the business now operates

We stayed as the business grew

We began looking after a London business in its early days. It now operates in eight US cities, and we still do its accounts.

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Since 2015

Still looking after early clients

Many businesses that joined One Abacus in its first years are still with us.

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Two of us

The accountant doing the work answers

Ryan and Simon do the work and take the calls. There’s no call centre or appointment needed for a question.

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Cobbled courtyard at the Brixton business centre with people outside

Why I set up One Abacus

Ryan Morton FMAAT, Founder and Principal Accountant

Fellow Member of the AAT Based in Brixton Works with Simon McDonagh Answers the phone

I used to sell tax-efficient payroll for an umbrella company, but I stopped believing the product served the people buying it. In 2015, I set up One Abacus to give small business owners something more useful.

If it feels quite pricey, our price includes everything you need: unlimited advice, the software, payroll, VAT and all the annual filings. Nothing is added on top. Have a ring round and compare a few prices so you find the right fit.

Call or email and you’ll reach me or Simon, with no appointment needed.

More about us

In Brixton, across South London, or by phone

Our office is at Coldharbour Works, 245a Coldharbour Lane, London SW9 8RR, with office visits by appointment only. We work with businesses across Brixton, Camberwell, Streatham, Clapham, Dulwich, Peckham, Herne Hill and the neighbouring boroughs. Contractors and companies elsewhere in the UK work with us by phone, video and cloud software.

One Abacus
Coldharbour Works, 245a Coldharbour Lane, London SW9 8RR
Office visits by appointment only
020 8670 7595 · info@oneabacus.com
See our locations

How we get things moving

Start with a few quick questions, then Ryan will tell you plainly what needs doing and what it will cost.

1

A proper conversation first

Ryan asks what you do, who your customers are, how the business is set up and what is worrying you. He then explains what HMRC expects from you and your company this year, by phone or video.

2

Your fee goes in writing

We agree one fixed monthly fee before any work starts, with FreeAgent or Xero included. It does not change mid-year, and conversations are never billed separately.

3

We set up and take over

We handle any PAYE or VAT registrations, configure the software, link the bank feed and show you how to use it. If you are changing accountant, we arrange the handover and pick up the next deadlines.

There is no tie in, and the questions that come up along the way are covered by the fee. You’ll know what it costs before we begin.

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The questions people ask first

Here are plain answers to the questions that usually come up before someone starts.

What do Accountants in South London charge for a small limited company?

The cost depends on what the company needs, including payroll, VAT and the annual filings. Our fee is fixed and agreed in writing before work starts, with the included work listed plainly. We work it out from your company’s own set-up so you can compare like with like.

Do Accountants in South London only work with local businesses?

No. We meet South London clients by appointment and work with companies elsewhere in the UK by phone, video and cloud software. We look at where you are and how you prefer to work before recommending the practical set-up.

When do I have to register for VAT, and what happens to my prices?

VAT registration depends on your rolling taxable turnover and the type of sales you make. Registration can affect your prices, invoices and ongoing admin. We check your own sales and pricing before explaining when registration applies and what needs to change.

Should I stay a sole trader or set up a limited company?

The right answer depends on your income, costs, clients and plans for the business. A company brings different filing duties and changes how you take money out. We compare both routes using your own circumstances and explain what each would mean.

How do contractors pay themselves, and where does IR35 come in?

A contractor may take money through salary and dividends, but the company must have the money available and follow the tax rules. IR35 is considered contract by contract and can change how the engagement is taxed. We review your contract and company position before explaining the practical options.

Can you take over from my current accountant part way through the year?

Yes, there is no need to wait for the year end. We arrange the handover, check the next deadlines and set up FreeAgent or Xero where needed. We use your company’s own dates and current position to decide what should happen first.

Start with a few quick questions

Answer a few quick questions and get a personalised recommendation. If there is a fit, Ryan will talk it through and arrange the free review by phone or video.