HMRC is moving towards mandatory eInvoicing from 2029, but most small and medium‑sized businesses are still relying on PDFs and paper, leaving a lot of work to do over the next few years. Now is a good time to understand what eInvoicing is, how it differs from emailed PDFs, and what practical steps you might take between now and 2029.

What is e‑invoicing – and what doesn’t count?

HMRC’s research uses a very specific definition of an eInvoice. An eInvoice is an invoice that is issued, sent and received in a structured data format, so that it can be processed automatically by software without anyone re‑keying information. 

Crucially, this definition excludes PDF or email invoices.

Many businesses currently send invoices as PDF attachments and understandably assume they are already ‘eInvoicing’, but those PDFs are classed as unstructured documents that still need manual handling. From April 2029, HMRC’s planned regime will require structured, machine‑readable data to flow directly between systems, rather than documents travelling by email.

What’s been announced?

In the Autumn Budget 2025, the government announced plans to make eInvoicing mandatory for VAT invoices from 1 April 2029. This will apply across VAT‑registered businesses, and sits alongside wider plans to reduce paperwork, strengthen VAT compliance and modernise the tax system.

HMRC has already commissioned research into SME usage and attitudes to eInvoicing, and launched a consultation in early 2025 on standardising electronic invoicing and increasing adoption across the UK. The consultation and research are intended to inform the detailed design of the rules, including technical standards and the support businesses may need.

What HMRC’s research says…

HMRC’s telephone survey around SME readiness for e-invoicing covered 800 VAT‑registered SMEs across sectors and regions, with data weighted to reflect the wider SME population. The findings will feel familiar to many owner‑managed businesses: awareness is reasonable, but genuine adoption is still low.

Key findings include:

• Around 59% of SMEs said they were familiar with the definition of eInvoicing used in the research.
• Only 29% reported using eInvoicing at all, with use higher among medium‑sized businesses (36%) than smaller ones (around 29%).
• Only 10% of SMEs both send and receive eInvoices; more receive them (24%) than send them (15%).
• PDFs or emails are overwhelmingly the main method: 95% use them to send invoices and 98% to receive them, with 80–89% saying emailing PDF is their most commonly used format.
• Paper and post are still very common: 36% of SMEs send paper invoices and 78% receive them, with paper use particularly high in transport, retail and accommodation.
• Most SMEs use some form of accounting software, including Sage, Xero and QuickBooks; only 5% reported using no accounting software at all. 

Despite HMRC sending an email bulletin mentioning e‑invoicing to over 100,000 recipients, only 6% of surveyed SMEs recalled seeing any HMRC communications about eInvoicing. Those who were very familiar with eInvoicing were more likely to have seen the messages, suggesting that many smaller businesses are not yet fully engaged with the coming changes. 

Sector‑specific awareness gaps

The research also highlights that familiarity varies by sector. 

A higher proportion of SMEs in manufacturing and construction reported being ‘not at all familiar’ with eInvoicing compared with other sectors (around one‑third of respondents in that group).

By contrast, businesses in professional services and other business services tended to report higher familiarity and usage.

Why the government is pushing eInvoicing

The government sees eInvoicing as a way to improve business efficiency and tax compliance at the same time. Because eInvoices are structured data, they can feed directly into accounting and tax systems, speeding up record‑keeping and reducing manual errors.

Evidence from the UK and overseas suggests several benefits:

• Lower processing costs: Research for DBT and HMRC suggests eInvoicing can cut invoicing costs by 60–80%, largely by removing manual data entry and paper handling.
• Improved cash flow: Faster, automated invoice delivery and processing can reduce delays from errors or lost documents; some adopters report invoices being paid almost twice as quickly as paper equivalents.
• Fewer late payments: Markets with established e‑invoicing regimes have seen late payments fall by around 20%, with estimated annual savings for small firms in the region of £11,000 in some studies.
• Productivity gains: Automation frees up time previously spent chasing, keying and reconciling invoices, with some analysis suggesting more than a two‑times return on investment within two years.
• Better compliance and fraud control: Centralised, digital records and system‑to‑system exchange help support audit trails, VAT controls and the detection of duplicate or tampered invoices.

While these are averages and will vary business‑by‑business, they illustrate why HMRC and the wider government are investing in the shift.

What does this mean for business owners?

Although mandatory eInvoicing is not expected to start until April 2029, the research suggests a sizeable gap between where many SMEs are today and where they will need to be. For owner‑managed businesses still heavily reliant on paper or simple PDF/email invoicing, the change could feel significant if left to the last minute.

On the other hand, firms already using cloud accounting software (Sage, Xero, QuickBooks and similar) may find that the change process is largely taken care of through future software updates, provided they keep their systems current and use the eInvoicing features once available. The bigger challenge may lie in changing habits and processes, including persuading customers and suppliers to move away from PDFs and paper, setting up new workflows, and training staff.

Practical steps you can take…

You don’t need to switch everything overnight, but 2029 is close enough that initial planning is sensible and an awareness of the coming requirements essential. 

The following actions may be useful:

1. Review how you currently issue and receive invoices
   • Note the split between paper, PDFs/emails and any existing structured formats or portals.
   • Identify customers or suppliers who already use more advanced systems; they may become your early adopters for eInvoicing.
2. Check your accounting software roadmap
   • Check how your software provider is going to support the eInvoicing requirement.
   • Make sure you are consistently on a supported, up‑to‑date version of your software so that future eInvoicing tools will be available to you.
   • Xero users can already find details of the process on Xero Central. This link will tell you how to register to receive eInvoices, and this one will tell you how to send an eInvoice.
3. Reduce reliance on paper
   • Where possible, encourage customers and suppliers to move from paper to digital invoicing as an interim step.
   • Even before full eInvoicing, cutting down paper can deliver time and cost savings and simplify record‑keeping.
4. Improve data quality in your systems
   • eInvoicing works best where customer and supplier records are accurate and consistent. Use the coming changes as an opportunity to tidy up contact details, VAT numbers and coding structures in your accounts system.
5. Factor eInvoicing into system upgrades and process changes
   • If you’re thinking about changing accounting software, billing systems or internal processes in the next few years, consider whether they position you well for 2029.
   • Avoid investing in heavily paper‑based or PDF‑only workflows that may need to be revisited once the detailed rules are finalised.
6. Keep an eye on HMRC guidance and consultations
   • As always, HMRC’s initial research and consultation are only the first steps; further guidance and technical detail will follow as the deadline for implementation draws closer.
   • Building eInvoicing into your planning now should mean fewer surprises as requirements become clearer.
   • We’ll keep clients up to date as the deadline draws closer.

As ever, if you’re unsure of the requirements of the new eInvoicing regime, please get in touch and we’ll help as much as we can.

You can see more around the results of the recent research here.