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
Get a free quote
A few quick questions, then a plain recommendation and a fixed monthly fee in writing. About two minutes. No monthly tie in.
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.
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!
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.
One Abacus has provided me a comprehensive service, very professional accountant, but friendly at the same time, maximum availability, I couldn't be happier.
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.
- 22ndevery month
Payroll and PAYE
Payslips, the submission to HMRC and the PAYE payment for you and anyone you employ.
- 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.
- 9mafter your year end
Year-end accounts
Filed with Companies House on time, built from books that are already up to date.
- 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.
- 14dafter your review date
Confirmation statement
The yearly check of your company details at Companies House.
- 31 Janevery year
Your self assessment
Your own return as a director or freelancer, with any payment on account explained before it lands.
- 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.
See what this would cost youWhat changed when we stepped in
These are real client stories, told without names.
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.
Get a quoteWe 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.
Get a quoteStill looking after early clients
Many businesses that joined One Abacus in its first years are still with us.
Get a quoteThe 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.
Get a quote
Why I set up One Abacus
Ryan Morton FMAAT, Founder and Principal Accountant
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 usThe jobs that leave your desk
Packages are available from £150 + VAT a month. One fixed monthly fee covers the software, advice and agreed filings, with the full price put in writing before we start.
Stop rebuilding a year at the deadline
We prepare the year-end accounts, corporation tax return and confirmation statement from books kept up to date.
ContractorsGet set before the first invoice
We help contractors form and run the company, review IR35 for each contract and handle the filings that follow.
Self assessmentTake January off the worry list
We prepare your return, explain what is due and file it using the information we have checked with you.
VAT registrationKnow when VAT becomes your job
We check your rolling turnover, work through the effect on prices and handle registration when required.
PayrollMove payday out of your diary
We run payroll, prepare payslips and make the required submission to HMRC.
Company formationBuild the company in the right order
We form the company, deal with the registrations it needs and explain what changes once you become a director.
Director payPay yourself without guessing
We work through salary and dividends using your company’s position and explain what to set aside.
FreeAgent and XeroMake the software useful from day one
We configure FreeAgent or Xero, link the bank feed and show you how to invoice and save receipts.
Who we look after
We look after small businesses across South London, with many clients working in creative fields, contracting and consultancy.

My work started selling and the paperwork never caught up

We hired our first person and payroll landed on my desk

The client is ready, but I have no company to invoice from

The set is due, and the money admin waits until Sunday
We also look after Small businesses Freelancers Consultants Startups
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 AbacusColdharbour 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.
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.
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.
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.
Get a free quoteThe 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.