VAT sits in an awkward place for a lot of growing businesses. It feels administrative enough to deprioritise, yet the consequences of getting it wrong — penalties, interest, retrospective adjustments, and the time cost of putting it right — are entirely real. Poor VAT processes are costing UK businesses money, and in our experience, the cost is rarely a single dramatic error. It tends to be a slow accumulation of friction: transactions coded to the wrong rate, returns prepared from incomplete records, registration decisions made too late, cash not set aside in time.

The good news is that a significant chunk of that friction is genuinely automatable. Cloud accounting platforms, Making Tax Digital-compliant workflows, and well-configured rules can take a lot of the mechanical effort out of VAT preparation. The less good news is that automation only works as well as the data and commercial judgement sitting behind it. In this post, we set out where the real VAT risks live, what technology can and can't do about them, and what a properly managed VAT process should look like in 2026.

HMRC's own figures put the UK tax gap for 2023-24 at £46.8 billion — around 5.3% of total tax liabilities. VAT accounts for a significant share of that. Not all of it is fraud or deliberate avoidance; a large proportion is attributable to errors, failure to take reasonable care, and businesses simply not keeping up with their obligations as they scale.

For SMEs, the costs show up in three places. First, there are the direct penalties and interest charges from inaccurate returns or late filings. Second, there is the cash flow impact of not setting aside VAT on sales revenue — treating it as income rather than a liability held on behalf of HMRC is a mistake that can destabilise an otherwise healthy business when the quarterly bill arrives. Third, there is the management time cost: unpicking a year of miscoded transactions takes far longer than coding them correctly in the first place.

Delayed registration is particularly expensive. Businesses must register for VAT when taxable turnover exceeds £90,000 in any rolling 12-month period. Miss that threshold — even accidentally — and you're liable for the VAT you should have charged from the point you crossed it, whether or not you collected it from customers. Many businesses scale faster than their financial systems, and registration decisions can fall through the gaps. That's a structural process failure, not a one-off mistake.

Across our client base — FMCG businesses, hospitality operators, tech start-ups, internet retailers — the pattern of errors is fairly consistent.

Incorrect VAT rates

The UK VAT rate structure is more complicated than it looks. Standard rate at 20%, reduced rate at 5%, and zero rate all apply to different goods and services, and the boundaries aren't always obvious. A hospitality business selling both hot and cold food, or an e-commerce retailer with a mixed product range, can easily apply the wrong rate to a category of sales without realising it. This tends to be a configuration issue in the accounting software that compounds quietly over time.

Partial exemption and blocked input tax

Businesses that have both taxable and exempt supplies need to apply partial exemption rules to determine how much input VAT they can recover. This is an area where the gap between 'software says yes' and 'HMRC says yes' can be significant, and it requires commercial judgement rather than automation.

Poor record-keeping

Making Tax Digital for VAT has raised the bar on record quality, but incomplete or inconsistent bookkeeping remains common — particularly for businesses that process a high volume of low-value transactions, or where expense records are submitted late and reconciled in batches.

The thread connecting most of these issues is that they begin small and are only identified when a return is scrutinised or an inspection occurs. By then, the remediation is expensive.

We are genuinely enthusiastic about automation at OD Accountants — it's central to how we work. But it's worth being precise about what it does well.

At its best, a well-configured cloud accounting workflow means VAT returns are essentially compiled in real time. Transactions flow in from bank feeds, sales platforms, and expense tools; VAT codes are applied by rule; the MTD submission is prepared directly from the ledger. When it's working properly, the mechanical preparation of a VAT return is as close to zero-effort as makes no difference — a forum comment from earlier this year put it at 'precisely 0 seconds', which isn't far off the mark for a clean set of books.

More substantively, automation reduces the friction that causes errors. When coding is done consistently at the point of transaction rather than retrospectively at quarter-end, mistakes are far less likely to compound. Bank reconciliation done weekly in Xero is a fundamentally different exercise from doing it once a quarter in a spreadsheet.

Automation also provides a reliable audit trail. Every transaction, every adjustment, every submission timestamp is logged. That matters when HMRC asks questions.

The gains are real. For most SMEs, a properly configured cloud accounting stack will materially improve VAT accuracy and reduce preparation time. That's not a claim we make lightly — it's what we see in practice when businesses migrate from manual or legacy workflows.

Here is where we part company with the more evangelical automation pitch: technology can give you a false sense of control if you mistake reduced friction for reduced risk.

Automation doesn't know your business model. It won't flag that you've started selling into a new product category that carries a different VAT treatment. It won't notice that your turnover is approaching the registration threshold, or that a change in the structure of a service offering has altered the VAT liability. It will apply the rules it's been configured with, consistently and efficiently — which is fine when those rules are correct, and a source of systematic error when they aren't.

The businesses we see get into the most difficulty with VAT are often not the ones running manual spreadsheets. They're the ones who moved to cloud accounting, felt reassured by the automation, and stopped exercising critical oversight. VAT codes get set up at onboarding and never reviewed. Turnover grows but nobody checks whether the threshold has been crossed on a rolling basis. A new revenue stream gets coded to the nearest approximation rather than the correct rate.

Automation reduces manual friction. It does not replace the need for someone who understands your commercial position to review your VAT position periodically and flag when something has changed. That combination — clean automated workflow plus informed human oversight — is the actual answer to reducing VAT risk for a growing business.