Accounting software for small business. You run the business, we run the books.
AccountsOS is accounting software for small business that handles bookkeeping, invoicing, bills, payroll, expenses, VAT and reporting in one place, with an AI accountant called Finn doing the work. It replaces a stack of disconnected tools and an expensive accountant for £20 a month, with a 14-day free trial and no card required.
Tools replaced
5+ in one
Flat monthly fee
£20/month
Ask in plain English
Chat or voice
Free trial
14 days, no card
Running a small business means wearing every hat at once. You win the work, you do the work, you invoice for the work, then you chase the people who have not paid for the work. Somewhere in between you are meant to run payroll, pay your suppliers, keep on top of VAT, and close the month so you actually know whether you made any money. Most small business owners do this across half a dozen tools that do not talk to each other, plus an accountant who takes three days to answer a one-line question and sends a bill at the end of the month regardless.
That is the problem AccountsOS exists to fix. It is accounting software for small business that brings every one of those jobs into one place and puts an AI accountant, Finn, in charge of the routine work. You still run the business. We run the books. This guide walks through exactly what good small business accounting software should do in 2026, the real pains a growing business with a team and payroll feels, and how each one maps to a feature that takes it off your plate.
What should small business accounting software actually do?
When a business is just you and a laptop, a spreadsheet and a shoebox of receipts can limp along. The moment you take on staff, send more than a handful of invoices a month, register for VAT, or start buying from suppliers on credit, that approach falls apart. You need software that covers the full cycle of money in and money out, not just one slice of it.
Here is the checklist of what a complete small business accounting platform should include. Use it to judge any tool you are considering, AccountsOS included.
| Capability | Why a small business needs it | In AccountsOS |
|---|---|---|
| Bank feeds + AI categorisation | Stop hand-typing every transaction into a spreadsheet | Yes, AI categorises automatically |
| Invoicing + chasing | Get paid faster, see what is overdue | Yes, list and calendar views |
| Bills + supplier payments | Know what you owe and when | Yes, with payment tracking |
| Payroll (PAYE, NI, pensions) | Pay your team and stay RTI compliant | Yes, posts to the ledger |
| Expense claims + approvals | Reimburse staff without spreadsheets | Yes, multi-currency, approver flow |
| VAT returns + MTD | File correctly and on time | Yes, standard and flat-rate |
| Real-time reports (P&L, balance sheet) | Know if you are actually profitable | Yes, from a real general ledger |
| Plain-English answers | Understand the numbers without a degree | Yes, chat or voice with Finn |
If your current setup is missing two or three of these, you are doing them manually or paying someone else to. That is the gap that costs growing businesses the most time. See the full breakdown on the features page.
The seven things eating a small business owner's week
Before the features, the feelings. These are the recurring jobs that pull a growing business owner away from the work that actually makes money. If you recognise more than three of these, you have outgrown spreadsheets and a once-a-month accountant.
Running payroll every month
RTI submissions, employer National Insurance, pension auto-enrolment. Miss a step and HMRC notices.
Chasing late payers
An invoice sent is not cash received. The chasing falls to you, usually at the worst possible moment.
Paying suppliers on time
Bills pile up, due dates blur, and you only find out you owe someone when they call.
Closing the month
Reconciling the bank, tidying categories, and producing a P&L you actually trust takes a full day.
VAT returns and MTD
Quarterly, unavoidable, and easy to get wrong if your books are not reconciled underneath.
Knowing your cash position
Across multiple income streams and currencies, what you can actually spend is never obvious.
The seventh, and the one that quietly drains the most, is juggling the tools themselves. One app for invoicing, another for payroll, a third for expenses, a spreadsheet for VAT, and an accountant who needs a copy of all of it before they can help. Every handoff is a chance for a number to go wrong.
How AccountsOS takes each one off your plate
Every pain above maps to a feature that does the work for you, all in one platform with a single source of truth underneath: a real double-entry general ledger. Here is how each job gets handled.
How does AccountsOS run payroll for a small team?
AccountsOS runs payroll for your employees, calculating PAYE, employer National Insurance and pension contributions, then posting the payroll journal straight into your general ledger so your reports stay accurate without a second entry. Because payroll lives in the same place as everything else, the salary leaving your bank account is already accounted for, not a mystery transaction you reconcile later. If you are weighing up a new hire, the employer NI calculator shows the true cost before you commit, and the full mechanics are covered in the payroll guide.
How does it help me get paid faster?
You create, send and track invoices inside AccountsOS, switching between a list view and a calendar view to see what is due when, and mark them paid in a click. When an invoice goes overdue, Finn flags it so you chase before it becomes a cashflow problem. Because invoicing sits next to your bank feed, a payment that lands in your account is matched to the right invoice automatically, so you are not reconciling weeks of receipts by hand at month-end.
How does it manage bills and supplier payments?
Forward a supplier bill to your inbox or upload it, and AccountsOS reads it, records what you owe and when it is due, and tracks part-payments against it. You see a clear picture of money going out alongside money coming in, so the supplier who calls about an unpaid invoice never catches you off guard again.
How does the agentic month-end close work?
Month-end is where most small businesses lose a day. In AccountsOS it is agentic: Finn reviews your month, flags anything that looks off, an uncategorised transaction, a duplicate, a VAT mismatch, and presents it to you as a short list. You clear the flags and lock the period. What used to be a full day of reconciliation becomes a ten-minute review, and the numbers underneath are correct because they come from a real general ledger, not a guess.
How does it handle VAT and Making Tax Digital?
AccountsOS calculates your VAT return from your actual transactions and supports both the standard scheme and the flat-rate scheme. The figures are drawn from the same general ledger that produces your P&L and balance sheet, so the return reconciles to your accounts rather than living in a separate spreadsheet. It is built for Making Tax Digital, so filing is part of the workflow, not a separate chore. The VAT guide explains which scheme suits your business.
How does it manage my team's expenses?
Staff submit expense claims by forwarding a receipt or snapping a photo, the AI reads it and extracts the amount, date and category, and the claim moves through an approver workflow so a manager signs off before reimbursement. Multi-currency claims convert automatically with the right exchange rate, which matters the moment you have someone travelling or buying from an overseas supplier.
How do I see my cash position and reports?
AccountsOS produces a real-time profit and loss statement, balance sheet and VAT summary, all built from your double-entry general ledger. Across multiple income streams and currencies, you get one honest view of where you stand. And you do not need to read a report to get an answer: ask Finn in plain English, by chat or voice, questions like "how much did I spend on software last quarter?" or "when is my next VAT deadline?" and you get a straight answer in seconds. Automating the bookkeeping underneath is what makes all of this possible, which you can read about on the automate bookkeeping page.
The tools you can replace, and what you save
The hidden cost of running a small business is not any single subscription. It is the stack of them, plus the accountant on top, plus the hours you spend moving data between them. Here is a typical small business software bill, and what AccountsOS folds into one flat fee. Figures are indicative monthly costs for a small UK business; your own prices will vary.
| What you are paying for | Typical separate cost | In AccountsOS |
|---|---|---|
| Accounting software (Xero, QuickBooks) | £30 to £70/mo | Included |
| Payroll add-on | £5 to £25/mo | Included |
| Invoicing / payments tool | £10 to £30/mo | Included |
| Expense management app | £5 to £15/mo per user | Included |
| VAT / MTD bridging software | £5 to £15/mo | Included |
| Accountant for routine bookkeeping | £150 to £300/mo | Finn does it |
| Total | £205 to £455/mo | £20/mo |
A small business spending the middle of that range, around £300 a month, saves roughly £3,360 a year by consolidating onto a single £20 platform, before you count the hours you stop spending moving numbers between tools.
A worked example: a month in the life of a small agency
Take a small design agency, three staff, VAT-registered, turning over around £240,000 a year. On the old setup, the founder spends the first week of June reconciling May. They log into the invoicing tool to see who has paid, cross-reference the bank statement by hand, export a CSV for the accountant, run payroll in a separate app, and email a spreadsheet of staff expenses for approval. The VAT return for the quarter to 31 May is due by 7 July, and they will not start it until the last minute because the books are not reconciled.
On AccountsOS, May is already reconciled because the bank feed and AI categorisation ran all month. On 1 June the founder opens month-end close. Finn has flagged three things: one invoice for £4,200 marked overdue, a duplicate £89 software charge, and a staff expense claim of €320 awaiting approval. The founder chases the overdue invoice, deletes the duplicate, approves the expense, which converts to £274 at the day's rate automatically, and locks the period. Total time: under fifteen minutes.
Payroll for the three staff ran on schedule, with PAYE and employer NI calculated and posted to the ledger. The VAT return for the quarter is already 95 percent prepared because the numbers come straight from the general ledger, so filing it before 7 July is a review, not a scramble. The week the founder used to lose to admin is back in the business.
VAT for small business: standard scheme vs flat-rate scheme
Most VAT-registered small businesses choose between the standard scheme and the flat-rate scheme. AccountsOS supports both, and Finn can tell you which works out cheaper for your business. Here is how they differ.
| Feature | Standard scheme | Flat-rate scheme |
|---|---|---|
| How VAT is calculated | VAT charged minus VAT reclaimed on purchases | A fixed percentage of gross turnover |
| Reclaiming VAT on costs | Yes, on most business purchases | Generally no, except some capital assets over £2,000 |
| Best for | Businesses with significant VATable costs | Businesses with low costs, e.g. services |
| Record-keeping | More detailed, every input tracked | Simpler, fewer calculations |
| Eligibility | Any VAT-registered business | Turnover under £150,000 (excl. VAT) to join |
A consultancy with low overheads often pays less on the flat-rate scheme, while an agency buying software, equipment and subcontractors usually does better on the standard scheme because it can reclaim the VAT on all of that. AccountsOS handles the 9-box VAT calculation for either, and the figures reconcile to your accounts because they share the same ledger.
Do you still need a traditional accountant?
The honest answer for most small businesses is no, not for the day-to-day. The work you have traditionally paid an accountant for, categorising transactions, reconciling the bank, preparing VAT returns, producing management accounts, answering "can I expense this?" questions, is exactly what Finn does, in seconds rather than days, with a proper double-entry ledger underneath so it is correct rather than approximate.
What you are really paying a traditional accountant for is often availability you do not get: the three-day reply time, the bill that arrives whether or not you asked anything that month, the sense that your own numbers are locked behind someone else's schedule. AccountsOS is the accountant. It answers immediately, it does the work continuously, and it costs £20 a month flat. Some directors still keep a human for an annual sign-off or one-off tax planning, and that is fine, but the recurring fee for routine work goes away.
Switching from Xero, QuickBooks or a spreadsheet
Moving your books is the part people dread, and it is the reason many stay on software they have outgrown. AccountsOS makes it painless. You export your data from Xero, QuickBooks, FreeAgent, Sage, Wave or others, and the AI maps your existing chart of accounts to AccountsOS categories automatically, so you are not re-coding hundreds of accounts by hand. You review the mapping, override anything you want, and import. Transactions that come in uncategorised get categorised by the AI in the background.
If you are starting from a spreadsheet, it is even simpler: upload a bank statement, in CSV or PDF, and AccountsOS extracts and categorises the transactions for you. Either way, you are running on a real accounting system within minutes, not migrating for weeks.
Frequently Asked Questions
What is the best accounting software for a small business?
The best accounting software for a small business is one that handles everything in one place: bookkeeping, invoicing, bills, payroll, expenses, VAT and reporting, so you are not stitching together five separate tools. AccountsOS does all of this with an AI accountant called Finn that categorises transactions, chases late payers, prepares your VAT return and runs your month-end close. It costs £20 a month with a 14-day free trial and no card required.
Does AccountsOS do payroll?
Yes. AccountsOS runs payroll for your small team, calculates PAYE, employer National Insurance and pension contributions, and posts the payroll journal straight to your general ledger so your reports stay accurate. You can model the employer NI cost of a new hire before you commit using the employer NI calculator. Payroll sits alongside your invoicing and bills rather than in a separate app you reconcile by hand.
Can it handle invoicing and chasing payments?
Yes. You can create, send and track invoices, see them in a list or calendar view, and mark them paid. When an invoice is overdue, Finn can flag it so you chase before the cash gap bites. Because invoicing lives in the same place as your bank feed, a paid invoice is matched to the incoming payment automatically rather than reconciled manually weeks later.
How much does small business accounting software cost?
AccountsOS is £20 a month with a 14-day free trial and no card required to start. One flat fee covers bookkeeping, invoicing, bills, payroll, expenses, VAT, MTD and reporting. That typically replaces several separate subscriptions plus the £150 to £300 a month many small businesses pay an accountant for slow, reactive support.
Do I still need an accountant?
Most small businesses use AccountsOS as their accountant. Finn does the day-to-day bookkeeping, answers your questions in plain English, prepares your VAT return and runs your month-end close, with a real double-entry general ledger underneath so the numbers are correct, not estimated. Some directors still keep a human for a once-a-year sign-off or complex tax planning, but the routine work that used to cost you monthly fees is handled.
Can it replace Xero or QuickBooks?
Yes. AccountsOS covers the same core jobs as Xero and QuickBooks, bookkeeping, invoicing, bills, VAT, reporting and bank feeds, and adds an AI accountant that does the work rather than handing you more forms to fill in. You can import your existing data from Xero, QuickBooks, FreeAgent, Sage and others, and the AI maps your old chart of accounts to AccountsOS automatically, so switching does not mean starting from scratch.
Does it handle VAT and MTD?
Yes. AccountsOS calculates your VAT return from your real transactions, supports both the standard and flat-rate schemes, and is built for Making Tax Digital. The VAT figures come from your double-entry general ledger, the same source as your P&L and balance sheet, so the return reconciles to your accounts rather than being a separate spreadsheet.
Can it manage my team's expenses?
Yes. AccountsOS handles expense claims for your team, including multi-currency claims with automatic FX conversion and an approver workflow so a manager signs off before anything is reimbursed. Staff can forward a receipt by email or snap a photo, the AI reads it and extracts the detail, and the claim flows into your accounts once approved.
Everything in one place, off your plate
Payroll, invoicing, bills, VAT, expenses and reporting, with an AI accountant doing the work. One flat fee instead of a stack of tools and an expensive accountant.
Get Started Free£20/month - 14-day free trial - No credit card required