Best Bookkeeping Software for Self-Employed: Cash Basis Test

In April 2024, HMRC changed the rules on how UK sole traders are legally expected to keep their accounts. The Finance (No. 2) Act 2023 made cash basis the legal default for all self-employed people. Most bookkeeping software platforms never updated their defaults to match. Set up a new account on many of the most widely advertised tools today and the software will record your income when you raise an invoice, not when a customer pays you. That is accruals accounting. It is not what HMRC now expects, and it is not how a plumber, electrician, or freelance designer actually runs their business.

That is the catch nobody mentions when you search for the best bookkeeping software for self-employed.

Why the April 2024 Change Was Not Reflected in Your Software

Before April 2024, cash basis was optional. Sole traders earning under £150,000 could elect to use it, but the default was accruals: income recorded on invoice, expenses recorded when billed. Most bookkeeping software was built around accruals, because accruals is how medium-sized businesses, limited companies, and the accounting profession generally operates. Sole traders were an afterthought in platforms designed for companies with finance teams.

The Finance (No. 2) Act 2023 reversed this. From April 2024, cash basis is the default for all sole traders. To use accruals, you must actively opt out. HMRC made the change because cash basis better reflects how self-employed people manage money: you think in terms of what has landed in your account, not what you have invoiced. The old £150,000 ceiling on cash basis eligibility was scrapped entirely; all sole traders can now use it regardless of turnover.

The software market has not caught up uniformly. Some platforms, particularly those built specifically for the UK self-employed market, now prompt users to choose their accounting basis at setup or default to cash basis for sole trader account types. Others, particularly platforms that serve enterprise and small business customers internationally, still default to accruals with cash basis buried in advanced settings.

The consequence is that thousands of self-employed people are doing their books the wrong way without knowing it, because nobody asked them which method they wanted and the software decided for them.

How to Tell Which Method Your Software Is Currently Using

You do not need an accountant to check this, though an accountant will certainly notice if you do not. Three tests reveal your current accounting basis without logging a support ticket:

The invoice test. Raise a test invoice and do not mark it as paid. Open your income report or profit and loss statement. If the invoice amount appears as income before you mark it paid, you are on accruals.

The settings test. Go to your software's company settings, accounting settings, or tax preferences. Look for "accounting basis," "VAT accounting," or "accounting method." If it says "standard," "traditional," or "accruals," note it and investigate further. If you cannot find the option at all within three clicks, contact the software's support team.

The bank reconciliation test. At month end, does your software's profit figure roughly match your actual bank receipts for the month? If it is consistently higher than your bank shows and you have unpaid invoices outstanding, you are almost certainly on accruals.

Why the Accounting Method Matters More Than Any Feature on a Comparison Table

Every comparison article about the best bookkeeping software for self-employed leads with the same features: bank feeds, receipt scanning, invoicing, mobile app, price per month. These are genuine considerations. But they are secondary to whether the software calculates your taxable profit correctly.

Under accruals, a freelance graphic designer who invoices £4,000 in March and gets paid in May records £4,000 as income in the tax year ending 5 April, even though the money has not arrived. On cash basis, that £4,000 is income in the year it is received. If the designer's software defaults to accruals and she does not know it, she may owe income tax on money she has not yet received, in the wrong tax year.

For a sole trader earning £60,000 a year with typical payment terms of 30 to 60 days, the difference between accruals and cash basis around 5 April can easily be £3,000 to £6,000 in timing differences. That is not a rounding error. That is a real difference in the Self Assessment payment due in January, on money that may still be sitting in a client's bank account.

The best bookkeeping software for self-employed is, at minimum, the software that calculates the correct figure. Every other feature is working towards either the right answer or the wrong one.

The MTD ITSA Dimension: Four Potentially Wrong Submissions a Year

Making Tax Digital for Income Tax Self Assessment goes live for sole traders earning over £50,000 in April 2026, with the £30,000 threshold following a year later. Under MTD ITSA, you will submit quarterly updates directly from your bookkeeping software to HMRC, four times a year. As explored in Make Tax Digital Software Does Three Things. Most Do Only Two., not all platforms can handle all three required functions: digital record-keeping, quarterly submissions, and the end-of-year declaration.

Add the cash basis dimension and the filter tightens further. If your software submits quarterly figures on an accruals basis when your taxable profit should be calculated on cash basis, every quarterly update will be inconsistent with your final Self Assessment. HMRC receives quarterly updates as provisional figures and compares them against the year-end return; a persistent, systematic discrepancy across four quarters will attract attention.

More practically, quarterly bookkeeping on accruals is significantly more work than on cash basis. Each quarter, you need to track which invoices have been paid and which are outstanding, because that determines what counts as income for the period. On cash basis, the question is simpler: what came in, and what went out? For a self-employed tradesperson checking their books at quarter end, that difference in complexity is not trivial across four quarters a year.

The Self Employment Accounting Software: The Year-Two Trap post covers how the second year of MTD catches many sole traders unprepared. The accounting basis problem is exactly this kind of slow-burn trap: easy to overlook in year one, difficult to correct once the first set of quarterly submissions has already been filed.

What the Best Bookkeeping Software for Self-Employed Actually Gets Right

Rather than ranking specific platforms, the more useful test is what to look for when evaluating any option:

1. Does it default to cash basis for sole trader accounts?

At account setup, does the platform ask which accounting basis you want, or explain which one it uses by default? Platforms designed for the post-April 2024 UK self-employed market should either default to cash basis or make the choice explicit at the point of registration. If setup completes without mentioning accounting basis at all, assume accruals and check the settings before recording a single transaction.

2. Is it on HMRC's MTD ITSA recognised software list?

Being on the MTD for VAT compatible software list is not the same as being on the MTD ITSA list. These are separate HMRC registers and software must be approved for each individually. HMRC Has Two Compatibility Lists. Is Your Software on Both? covers this distinction in detail. From April 2026, only software on the MTD ITSA list can submit quarterly income tax updates. A platform that is VAT-compliant only cannot legally fulfil your MTD ITSA obligation.

3. Does it handle the cash basis transitional adjustment?

If you have been on accruals and want to switch to cash basis, HMRC requires a transitional adjustment under BIM70060 to avoid double-counting income or expenses that were already recorded. A platform that lets you switch accounting methods with a single toggle and no explanation is either assuming you know what you are doing or has not thought through this scenario. Look for a platform that flags the need for a transitional calculation, or at minimum clearly suggests professional advice before switching.

4. Can you export your records in a format HMRC can inspect?

HMRC can request digital records going back up to six years. As discussed in Your Sole Trader Accounts Are Evidence. Treat Them That Way., the software you use needs to produce records in a readable, exportable format that is not dependent on the vendor's continued existence. A platform that stores your data in a proprietary format with no export option ties six years of compliance records to a subscription you may not renew.

5. Does the mobile experience reflect cash basis logic?

The Best Accounting Software for Self-Employed: The Mobile Test looked at how platforms perform on mobile in general. The cash basis corollary is more specific: if you can record a payment received on-site when a customer pays you cash or bank transfer, the software is designed around cash basis. If the mobile app is primarily for issuing invoices, with payment recording handled later on desktop, the workflow is accruals-first and the mobile app is decoration.

The Switching Question: When and How to Move

If you are currently on accruals and it is working without obvious problems, do you need to switch?

Accruals is not illegal. You can opt out of cash basis explicitly and HMRC will accept it. But you should have a documented reason: carrying significant stock, having large outstanding debtors at year end that you want to smooth across periods, or wanting to claim loan interest without the restrictions that apply under cash basis. For the overwhelming majority of sole traders who invoice for services and carry no stock, cash basis is both simpler and the legally assumed default.

If you are preparing for MTD ITSA, the start of the next tax year on 6 April is the cleanest point to switch. Open a new account in software that defaults to cash basis and appears on the MTD ITSA recognised list, migrate only your opening balances, and begin the new year on the correct footing. Do not attempt to convert historical accruals records mid-year in software that was not designed for the transition.

If you switch within a tax year, the transitional adjustment matters. You need to reverse accruals-based income for invoices not yet received as cash, and remove expenses recorded before payment was made. HMRC's guidance at BIM70060 covers the mechanics in full. Most bookkeeping platforms do not automate this process; it typically requires a manual journal entry or professional help from an accountant who knows the specific rules.

The Real Test for "Best"

The next time an article ranks bookkeeping software and awards top marks to the platform with the most integrations or the smoothest receipt-scanning experience, ask which accounting method that platform uses by default. Ask whether it is on HMRC's MTD ITSA list, not just the VAT list. Ask whether it handles the cash basis transitional adjustment, or whether it simply assumes users already know the difference between accruals and cash basis.

The best bookkeeping software for self-employed in 2026 is not the most sophisticated. It is the most correct: the one that calculates taxable profit on the method HMRC now expects by law, submits quarterly updates on that basis, and keeps records in a format that survives a compliance review six years from now.

That standard eliminates a significant portion of the market. It is a useful filter to apply before the monthly subscription begins.