Straightforward tax advice for offshore oil and gas contractors

Updated: 24th February 2026

If you are considering moving into work as an offshore contractor in the oil and gas industry, it’s important that you have all the facts when it comes to your tax obligations.

Here at One Two One Accounts, we know that tax affairs which stretch across international borders can be incredibly complex, and we have a great deal of experience in assisting offshore contractors to ensure tax compliance and efficiency.

That’s why we have put together this short, simple guide to everything you need to know about tax as an offshore contractor. So, let’s dive straight in.

Considering work as an offshore contractor in oil and gas?

According to figures from the most recent Offshore Energies UK Workforce Report (formerly Oil & Gas UK), the UK offshore energy sector directly and indirectly supported around 154,000 jobs in 2024.

Working offshore isn’t simply a career choice, it is a lifestyle choice, and it certainly isn’t suited to just anyone. Long rotations, time away from family, and demanding working conditions are all part of the package.

However, whilst the challenges can be large, so too can the payoffs. Competitive day rates and specialist skill premiums mean offshore roles remain highly attractive. It isn’t surprising, therefore, that the oil and gas industries attract thousands of eager workers each year who are looking for an exciting challenge and an unorthodox lifestyle.

But alongside the lifestyle and financial rewards comes an important responsibility: understanding your offshore tax position from the outset. Failing to do so can quickly erode the financial benefits of offshore work.

What does it mean to work offshore from a tax perspective?

When it comes to UK taxation, UK territory is designated as England, Wales, Scotland, Northern Ireland and the Continental Shelf. The Continental Shelf covers UK territorial waters, to a distance of 12 nautical miles from the coast, along with certain designated areas of the surrounding waters.

These designated areas are the UK sector’s oil and gas exploration and exploitation areas, and individuals working in these designated areas are what we know as offshore workers. For such workers, particular rules apply when it comes to tax and NICs regulations.

From an offshore tax perspective, the key question is not simply where you are physically located, but how that location is defined under UK legislation and any relevant international agreements.

Even a few nautical miles can make a significant difference to your tax treatment. So, understanding whether your work falls inside or outside UK tax jurisdiction is the first critical step in ensuring compliance.

What are the tax rules for offshore contractors?

Common-or-garden tax matters can certainly be complicated enough, never mind when tax affairs begin to cross international borders. Offshore tax introduces additional layers of complexity, particularly where residency, employer location and international treaties all interact.

Unfortunately, incorrect submissions can lead to substantial penalties, which have become a greater risk since major changes were introduced to offshore taxation rules several years ago. HMRC has increased its focus on cross-border compliance, making accuracy more important than ever.

The tax and National Insurance rules for offshore oil and gas workers are fairly complicated, and vary depending on if you:

• Work for a UK company
• Work within UK waters
• Are a foreign or UK national
• Work in a country that holds a Double Taxation Agreement with the UK (DTA)

Each of these factors can significantly alter your offshore tax obligations. For example, operating through a UK limited company may bring corporation tax and dividend considerations into play, while overseas contracts could trigger foreign tax reporting requirements.

I’m a UK resident. What are my tax obligations?

If you are a UK resident working offshore in the UK sector of the Continental Shelf, you are liable to pay UK tax, along with National Insurance.

Your worldwide income is generally taxable in the UK, meaning offshore earnings must be declared through self-assessment. Even if tax is deducted at source elsewhere, you may still need to report it. In some circumstances, Foreign Tax Credit Relief may apply to prevent double taxation, but this depends on the specific treaty terms in place.

Careful offshore tax planning can help ensure you are not overpaying and that all available reliefs are correctly claimed.

I’m a non-resident worker. What about me?

If you are registered as a resident in a country holding a DTA with the UK, you must check your country’s treaty for the specific terms of the agreement.

The vast majority of DTAs include the designated UK sector of the Continental Shelf in their definition of the UK. However, some do not, and in these instances, a contractor is not regarded as working within the UK.

Different DTAs outline different criteria for taxation. Many will exempt you from UK tax if you are contracted by an employer based abroad and you are outside of the UK for a certain length of time. Others will regard you as a UK resident for offshore tax purposes if you work within the UK sector of the Continental Shelf.

You may also have to pay UK National Insurance depending on factors such as whether a Social Security agreement exists between the UK and your country of residence. Because treaty wording can vary significantly, professional advice is strongly recommended before assuming exemption.

Why proactive offshore tax advice matters

One of the biggest mistakes offshore contractors make is only seeking advice once a problem arises. Proactive offshore tax planning can make a significant difference to both compliance and long-term financial outcomes.

Before starting a new contract, particularly if it involves a different jurisdiction, employer structure, or rotation pattern, it is essential to understand how your income will be treated. Small changes in contract terms, working days spent in UK waters, or residency status can materially affect your offshore tax position.

Forward planning also allows you to structure your affairs efficiently. This might include reviewing whether operating through a limited company is appropriate, ensuring allowable expenses are correctly recorded, or forecasting potential tax liabilities so you can budget accordingly.

Importantly, offshore tax rules can evolve as legislation changes or international agreements are updated. Staying informed helps you avoid unexpected liabilities and penalties down the line.

By taking a proactive approach, you not only reduce risk but also gain peace of mind, allowing you to focus fully on your role, confident that your tax affairs are structured correctly and working in your favour.

Still feeling unsure about your tax obligations?

Offshore tax rules are rarely straightforward and getting them wrong can be costly.

In most cases, getting the right advice as an offshore contractor is crucial to ensure compliance and maximise tax efficiency. Working closely with a professional can provide you with the clarity and confidence you need to focus on your role – not your paperwork.

Here at One Two One, our specialist accountants utilise their extensive knowledge and experience to assist with offshore tax compliance for contractors in the oil and gas industries. Looking for professional guidance? Contact us today to get the ball rolling.