22 September 2026 – written by Steffen Kemmerzehl – Friendly Assist Accountancy – The Accounting Hub
It does not take much for a UK business to become an international business. You might start selling to a customer in Germany, have a supplier in Türkiye, move yourself abroad for a few months, employ someone overseas, or set up a company because you are spending more time outside the UK.
The paperwork can then become considerably more complicated than the business itself.
That is particularly relevant right now for businesses moving goods between Great Britain and Northern Ireland. HMRC has confirmed that the new Trader Support Service platform will go live on 20 October 2026, with all new goods movements from that date needing to be submitted through the new platform. Existing TSS users are being asked to pre-enrol and update their details before the changeover.
The important point for a business owner is that the TSS change is only one part of the picture. If your business has customers, suppliers, directors, employees or operations in more than one country, it is worth looking at the wider tax and accounting position as well.
“I have overseas customers. Surely I just invoice them?”
This is one of the most common questions I come across with international clients, and the answer depends on what you are selling, who you are selling it to and where the customer belongs.
For example, imagine a Newcastle-based consultant who starts doing regular work for a German company. The invoices may look very similar to the UK invoices they have always issued, but the VAT treatment can be different. For many B2B services, the general VAT rule is that the place of supply is where the business customer belongs, although there are important exceptions. HMRC also expects businesses to keep appropriate evidence supporting the VAT treatment.
This is where international work can catch smaller businesses out. The fact that a customer is overseas does not automatically mean “no UK VAT”, and selling goods is different from providing services. There can also be local VAT, registration, customs or reporting obligations in the other country.
If you are regularly invoicing overseas customers, it is worth getting the treatment right before the transactions build up. Correcting a handful of invoices is much easier than trying to untangle several years of international sales later.
The bigger issue is often the person behind the company
I also regularly see situations where the business itself has not changed much, but the owner has. Perhaps you have a UK limited company but have moved to Spain. Maybe you have spent several months working from Germany while continuing to run your UK business. Perhaps you have returned to the UK after living abroad, or you are planning to move overseas while keeping your UK clients.
Those changes can affect your personal tax position, company residence, payroll, social security and sometimes the way the business itself is taxed.
A UK company does not automatically become straightforward simply because it was incorporated in the UK. Where the company’s actual management and operations take place can become relevant, particularly where the director is living and working abroad.
For an individual, residence and the source of income also matter. Someone who has moved country can find that the same income needs to be considered under two countries’ tax rules, with double taxation relief or a tax treaty potentially becoming relevant.
This is particularly important for people who have what looks like a simple arrangement: “I live abroad, but my UK company carries on as normal.” Sometimes it is perfectly manageable. Sometimes there are important questions that need answering before the arrangement continues.
“I only work abroad temporarily”
This is another situation worth checking rather than assuming.
A UK business owner might spend three or four months abroad while continuing to work remotely. An employee might move overseas temporarily. A director might spend most of the year in another country while still running a UK company.
The tax consequences depend on the facts, including where the individual is resident, where the work is physically carried out, how long they are there, and whether the company has created an overseas presence.
For businesses with international links, I would much rather have that conversation at the beginning. A short review can identify what needs monitoring and what records should be kept, rather than discovering the issue when another country’s tax authority or HMRC starts asking questions.
Northern Ireland is another area where small businesses can get caught out
The current TSS change is a useful reminder that international trading is not only about selling directly to customers overseas.
A business in England, Scotland or Wales moving goods to Northern Ireland needs to understand the relevant customs and VAT arrangements. The new TSS platform does not change the underlying legal obligations, but businesses using the service need to be ready for the move to the new system by 20 October.
If you are affected, HMRC says existing users will receive instructions from 1 October and should check their business details and permissions before the switchover.
For a small business owner, the practical question is often less about becoming a customs expert and more about making sure the customs activity, invoices, VAT returns and accounting records all agree.
This is where an international accountant can make life easier
You do not need to be a multinational company to have international tax issues. In fact, some of the situations that need the most care are ordinary small businesses and individuals whose circumstances have simply crossed a border.
That might be a UK company with a director living in Germany, a freelancer returning to the UK after several years overseas, a Newcastle business selling professional services to European customers, a company importing goods, or someone moving abroad while keeping their UK business.
At Friendly Assist Accountancy, I work with UK clients who have these sorts of international connections, as well as overseas individuals and businesses with UK tax or accounting responsibilities. The aim is not to make things more complicated than they need to be. It is to understand what is actually happening, identify the parts that matter for UK tax and accounting, and help you keep the records and returns in order.
If your business has started crossing borders and you are not completely sure whether your current accounting setup still fits, get in touch with Friendly Assist Accountancy. We can look at your particular circumstances and work out what needs attention, whether that is VAT, Self Assessment, company tax, residence, overseas income, Northern Ireland trading or simply getting your bookkeeping properly organised.
Helping you stay on top of your accounts and tax, wherever your business takes you.
I’m Steffen Kemmerzehl, an AAT Licensed Accountant at Friendly Assist Accountancy. I work with UK and international clients on tax residence, overseas income, pensions, property and other cross-border UK tax matters.
Please get in touch if you’re interested in arranging an appointment.
Further information
HMRC: Trader Support Service and the October 2026 platform change Trader Support Service platform change
HMRC: Trader Support Service guidance Trader Support Service guidance
HMRC: VAT place of supply of services VAT place of supply guidance