Compliance with HMRC is something most business owners think about at specific moments – when a return is due, when a payment is owed, when a letter arrives. In between those moments, it tends to fade into the background.
That approach works reasonably well when a business is small and its obligations are limited. It becomes progressively less adequate as the business grows, because growth brings new obligations, and those obligations do not always announce themselves clearly. A business that is managing compliance reactively can find itself behind without realising it – not through carelessness, but because the rules changed, or a threshold was crossed, or a new activity triggered a requirement that nobody thought to check for.
This article covers the main compliance areas that tend to become relevant as a business grows, and what staying on top of them actually requires. Thankfully, if you’re engaged with your accountant, they should manage this for you – you don’t need to be the expert in all of these areas – you just need to know who to bring in to manage them for you.
Understand That Your Obligations Change as the Business Changes
The compliance profile of a sole trader just starting out is very different from that of a limited company with employees, VAT registration, and a growing client base. The obligations that apply to a business depend on its structure, its size, its activities, and in some cases its industry. And they are not static – they change as the business changes.
The most common trigger points where new obligations arise are:
- Crossing the VAT registration threshold, currently £90,000 in taxable turnover over any rolling 12-month period
- Taking on the first employee, which introduces PAYE, National Insurance, and auto-enrolment pension obligations
- Incorporating as a limited company, which brings Companies House filing requirements, Corporation Tax, and director obligations
- Crossing the Making Tax Digital thresholds for Income Tax, which are being phased in from April 2026
- Beginning to trade internationally, which can affect VAT treatment and introduce customs obligations
- Taking on a business partner or investor, which may affect the structure and reporting requirements of the business
None of these trigger points are hidden. But they do require the business owner to be paying enough attention to recognise when they are approaching, and to have the right support in place to manage the transition before the obligation bites rather than after.
Get VAT Right From Registration
VAT is one of the areas where small mistakes accumulate into significant problems most readily. The rules around what is and is not VATable, how to handle partial exemption, how to treat expenses with a mix of business and personal use, and how to manage the transition around the registration threshold are all more nuanced than they might initially appear.
Registration must happen within 30 days of the end of the month in which turnover exceeds the threshold. Late registration means accounting for VAT on sales back to the date registration should have occurred – which can mean a significant liability on income for which no VAT was charged to clients.
Once registered, returns must be submitted and payments made on time. Under Making Tax Digital for VAT, records must be kept digitally and returns submitted through compatible software. The penalty regime for VAT non-compliance has been reformed in recent years and is now points-based, with financial penalties accumulating as points build up for missed returns and late payments.
Voluntary registration – before reaching the threshold – is worth considering if a significant proportion of clients are VAT-registered businesses who can reclaim the VAT you charge. The decision has pricing and administrative implications that are worth working through properly before committing.
Keep PAYE Running Correctly as the Team Grows
Payroll compliance becomes more complex as headcount increases, and the complexity is not always linear. A team of ten with a mix of full-time employees, part-time workers, and people on different pay arrangements has significantly more moving parts than a team of two, and the risk of an error in any given pay run is correspondingly higher.
The areas that most commonly create problems as businesses grow are:
- Tax codes that are not updated when an employee’s circumstances change – a second job, a change in personal allowance, a benefit in kind that has been added or removed
- National Insurance category letters applied incorrectly, particularly for employees who are over state pension age or who have multiple employments
- Holiday pay calculations that do not reflect the correct reference period for workers on variable pay, following legislative changes in recent years
- Statutory payments – sick pay, maternity and paternity pay – that are calculated or administered incorrectly
- New starters set up on the wrong tax code because a P45 was not obtained or a starter checklist was not completed
The Fair Work Agency, which launched in April 2026, has significantly increased the enforcement risk in this area. It can inspect payroll records without prior notice and pursue claims on behalf of workers who have not raised them individually. Businesses that are not confident their payroll is running correctly should treat that as a priority rather than a background concern.
Meet Your Companies House Obligations if You Are Incorporated
A limited company has filing obligations with Companies House that are separate from and additional to its HMRC obligations. These include an annual confirmation statement, annual accounts filed within nine months of the accounting period end, and notification of any changes to the company’s directors, registered office, or share structure.
These deadlines are fixed and do not move. Missing them results in penalties that escalate the longer the filing remains outstanding, and persistent non-compliance can result in the company being struck off. The accounts filed at Companies House are also public documents – visible to clients, suppliers, competitors, and potential investors – which means their quality matters beyond the compliance dimension.
As a company grows and its accounts become more complex, the preparation of statutory accounts is increasingly a task that benefits from professional involvement. Accounts that are technically compliant but poorly presented, or that raise questions a reader cannot easily answer, can affect how the business is perceived by parties who review them.
Stay Across Making Tax Digital
Making Tax Digital is HMRC’s programme requiring businesses to keep digital records and submit tax returns through compatible software. It is being rolled out in phases, and the obligations it creates depend on the type of tax and the level of income involved.
MTD for VAT has applied to all VAT-registered businesses since April 2022. MTD for Income Tax is being phased in from April 2026, starting with self-employed individuals and landlords with income above £50,000, with lower thresholds following in subsequent years.
For businesses not yet using compatible software, the direction of travel is clear and the window for a managed transition is narrowing. Getting onto a compliant platform now – with proper setup rather than a rushed migration to meet a deadline – is considerably less disruptive than leaving it until compliance becomes urgent.
Build Compliance Into How the Business Runs
The businesses that manage HMRC compliance most effectively tend not to be the ones that are most diligent about checking their obligations. They are the ones that have built compliance into the normal operation of the business, so that it happens as a matter of course rather than as a periodic project.
That means bookkeeping that is kept current, so that VAT returns and accounts can be prepared from reliable data without a reconstruction effort. It means payroll that is managed properly each month, not caught up retrospectively. It means a clear calendar of filing and payment deadlines, with reminders set well in advance. And it means an accountant who is sufficiently engaged with the business to flag when a threshold is approaching or a change in circumstances creates a new obligation.
Compliance does not have to be a burden. Managed proactively, with the right systems and support in place, it is largely invisible – something that happens in the background while the business gets on with the work that actually matters.
If you are not confident that your compliance obligations are fully in hand as your business grows, get in touch with the team at Atria. We can review where things stand and help you get ahead of anything that needs attention.
This article reflects HMRC requirements and legislation as at June 2026, including MTD thresholds and Fair Work Agency powers effective from April 2026. Rules and thresholds are subject to change. This article does not constitute legal or financial advice. For guidance specific to your circumstances, please speak to a qualified professional.
