The Definitive Guide to Contractor Working Structures

The Definitive Guide to Contractor Working Structures 

If you’re a UK contractor, you might be wondering how to best structure your business. Three of the most popular avenues are to work through an umbrella company, your own limited company, or as a sole trader. If you work in construction, you may also need to understand how the Construction Industry Scheme (CIS) affects how you’re paid and taxed.

So, which working structure is right for you? The immediate answer is that it depends. Each option has its pros and cons. That said, several factors should influence your decision, such as what work you do and whether it sits inside or outside tax laws like IR35. In this guide, we’ll compare each avenue and share a list of considerations to help you choose the best structure for your contractor business.

Working Structure Fast Definitions

When it comes to contractor working structures, there are no like-for-like comparisons. Each route affects how you are paid, how tax is handled, and how much responsibility sits with you.

• Umbrella company: You are employed by an umbrella company. They handle admin and pay you through PAYE, after deducting tax and National Insurance. The umbrella company charges a fee for this service.
• Limited company: You run your own company as a separate legal business, giving you more control over income, expenses, and planning. This also means managing company accounts, tax deadlines, filings, and director responsibilities.
• Sole trader: You work for yourself as a self-employed individual. This is usually simpler to set up and run than a limited company, but you are personally responsible for your tax, National Insurance, records and business debts.
• CIS: A tax deduction scheme for qualifying construction work. Contractors deduct tax from payments and pass it to HMRC on your behalf. It can apply whether you operate as a sole trader, through a limited company or through another eligible business structure.

Important Considerations for Choosing a Work Structure

Before you look at how each route works, it helps to understand the considerations you need to weigh up.

How IR35 Could Affect You

IR35 is a UK tax law that looks at whether a contractor working through an intermediary, such as a limited company, should be taxed more like an employee for a particular assignment. In simple terms, it asks whether the contractor is genuinely operating as an independent business or as an employee.

IR35 does not affect every working structure in the same way. If you work through an umbrella company, you are employed by the umbrella and paid through PAYE, so IR35 does not change how you are paid.

If you work directly as a sole trader, IR35 does not apply because you are not providing your services through an intermediary. The same applies if you work directly as a self-employed subcontractor under CIS. However, your contract and working practices must still support genuine self-employment.

IR35 is most relevant when you work through your own limited company. If an assignment is inside IR35, the income is taxed broadly like employment income. This reduces many of the tax efficiencies associated with operating through a limited company. If the assignment is outside IR35, the company continues to operate under the normal company tax rules, with more flexibility over allowable business expenses, pension contributions, retained profits and how profits are withdrawn.

Determining IR35 Status

Whether an assignment is inside or outside IR35 depends on the client. Public sector organisations and medium or large private sector businesses are generally responsible for making the determination. Where the client is a small private sector business, responsibility usually sits with the contractor’s limited company. Contractors may use an accountant or specialist adviser to support the assessment, but the legal responsibility remains with the party required to make the decision.

● Related: Need support navigating IR35? Check out our expert-led IR35 services.

Compliance and Legal Responsibilities

Each working structure comes with different legal responsibilities. If you run your own limited company or operate as a sole trader, you are responsible for meeting your legal and tax obligations.

If you work under CIS, you remain responsible for meeting the legal and tax obligations that apply to your business structure, even though contractors may deduct tax from your payments under the scheme.

If you work through an umbrella company, many of these responsibilities sit with the umbrella as your employer. Understanding where responsibility sits can help you choose the structure that best fits your circumstances.

Maximising Take-home Pay

No matter how long you’ve been contracting, maximising your earnings is likely to be high on your priority list. But the structure with the highest headline rate will not always leave you in the strongest net position.

Umbrella working may be simpler, but your income is processed through PAYE and the umbrella company charges a fee for its service. Sole trader and limited company working may offer greater flexibility over your finances, but this comes with more responsibility and hands-on involvement.

Another important factor is what your time is worth to you. Any time spent handling business administration is time taken away from earning, developing your business or enjoying your personal life. This brings us to another important consideration: the way you prefer to work.

How Do You Like to Work?

Contracting is stressful enough without having to work in a structure that clashes with your personality type and work preferences.

Do you want to focus on your work and not have to worry about business administration? In that case, you might prefer the simplicity of partnering with a reputable umbrella company and letting them handle your paperwork. Do you feel that dealing with tax, compliance, and pension contributions is a small price to pay for greater control over your finances and planning? Then becoming a sole trader or setting up a limited company might be a better fit.

Your preferences may also change over time. Someone trying their hand at contracting for the first time may need a different setup from someone building a long-term contracting business. With this in mind, let’s explore each type of work structure in greater depth.

How Umbrella Companies Work

Umbrella companies act as your legal employer. This route reduces the admin involved in contracting, as the umbrella company is responsible for collecting payments from clients and making the relevant deductions, including tax, National Insurance, and pension contributions.

Advantages of Using an Umbrella Company

• Easy setup: Umbrella working can be quick to start, making it useful for short-term contracts or contractors testing the market.
• Less admin: The umbrella company handles payroll and much of the employment admin, so you can focus on the assignment itself.
• PAYE employment-style support: You are paid through PAYE. Depending on your eligibility, you may have access to benefits such as holiday pay, pension contributions, and statutory payments.
• Easy to stop: If you stop contracting or decide to switch structure, there is no company to close down.

Disadvantages of Using an Umbrella Company

• Less control: You have limited influence over how your income is structured because pay is handled through PAYE.
• Lower flexibility around expenses: Expense claims can be more restricted than under alternative working structures.
• Provider fees: The umbrella company charges for its service, affecting your overall net position.
• Reliance on the provider: The umbrella company is responsible for processing your pay and making the correct deductions. Choosing a reputable, compliant provider can help reduce the risk of payment errors or unexpected tax issues.

Need help choosing an umbrella company?

At Brookson, we’re the umbrella company for thousands of UK contractors. If you’re looking for expert guidance on whether partnering with an umbrella company is the right choice for your business, please explore our service page and get in touch.

How Limited Companies Work

With a limited company, you complete work through a business you own and run. Clients contract with your limited company and pay your company for the work. You may then take money from the company through salary, dividends, expenses or other lawful routes, depending on the company’s position and your circumstances.

This gives you more control over how the business is set up and run, but it also makes you responsible for how the company is managed, including meeting the company’s legal and tax obligations.

Advantages of Using a Limited Company

• More control: You have greater flexibility over how the business manages income, expenses, pension planning and retained profits.
• Planning potential: If your contract is outside IR35, your company can usually manage income more flexibly, including how money is taken from the business and what is kept in the company for future use.
• Separate legal structure: The company’s finances are separate from your personal finances, which can offer a layer of protection if the business runs into difficulty.
• Strong fit for long-term contracting: A limited company can make sense if you plan to contract as a business rather than take on occasional assignments.
• Professional positioning: Some agencies and clients prefer to work with limited company contractors, especially for longer or more specialist engagements.

Disadvantages of Using a Limited Company

• Company obligations: You are responsible for keeping proper records, filing company accounts and meeting tax obligations.
• Professional support costs: Many contractors use a specialist accountant to help manage their company, which adds cost but reduces the pressure of handling everything alone.
• IR35 sensitivity: If a contract is inside IR35, some of the practical benefits of limited company working may be reduced.
• Less convenient to stop: If you stop contracting or switch structure, you may need to manage company closure or keep the company dormant.

How Sole Trading Works

When working as a sole trader, you contract in your own name or under a trading name. There is no separate company structure, so you are personally responsible for the financial and legal side of your work. You invoice clients directly, receive the income yourself and pay tax through Self Assessment.

This route is usually simpler than running a limited company, but it also gives you less legal separation. You are the business, which means you are personally responsible for how it is managed.

Advantages of Working as a Sole Trader

• Simple setup: Sole trading is usually quick to start because you do not need to form a company.
• Less formal admin: You still need to manage your tax and records, but there are fewer company obligations than with a limited company.
• Direct control: You manage the work, client relationship and business decisions yourself.
• Lower structural cost: There is no company to run and no umbrella provider fee. You may still need professional support, such as working with an accountant.

Disadvantages of Working as a Sole Trader

• Personal risk: There is no separate company structure, so business debts and legal responsibilities sit with you.
• Less tax planning flexibility: Your business income is treated as personal income, giving you fewer planning options than you would have with a limited company.
• No employment-style support: You are self-employed, so you need to plan for your own financial protection.
• Client or agency restrictions: Some clients or agencies may prefer, or require, a limited company or umbrella arrangement.
• Status risk: If the client treats you like an employee, it creates tax risk. HMRC could decide the arrangement is wrong, leaving you with additional tax or penalties to pay.

Need support managing your finances?

Juggling finances is often the trickiest part of running a contractor business. Brookson provides specialist accountancy support for sole traders and limited companies, helping you stay on top of your records, reporting and tax responsibilities.

Explore our accountancy services to see how we can help simplify your finances and reduce the administrative burden.

How the Construction Industry Scheme (CIS) Works

To recap, the CIS is a tax deduction scheme for subcontractors working in the construction industry. Rather than being a working structure in its own right, it sets out how contractors deduct tax before paying subcontractors. CIS can apply whether you operate as a sole trader, through a limited company or through another eligible business structure.

Before paying you, the contractor verifies your CIS status with HMRC. Depending on that status, they may make a deduction from your payment or pay you in full if you have gross payment status. Any deductions are passed to HMRC and credited against relevant tax liabilities.

For subcontractors paid under deduction, CIS enables payments towards tax to be made throughout the year. It also provides a standard process for payments between contractors and subcontractors in the construction industry.

Importantly, CIS deductions do not necessarily settle your final tax bill. You remain responsible for keeping appropriate records and meeting the reporting obligations that apply to your business. Deductions may also affect your cash flow. If too much has been deducted, you may need to claim a refund or set the excess against other liabilities, depending on how your business is structured.

Want to Learn More About CIS?

If you want to understand how CIS could apply to your circumstances, get tailored advice from Brookson’s contracting experts.

Explore our CIS page to get in touch.

Which Working Structure Is Right for You?

The right structure depends on more than take-home pay. Your industry, client expectations, contract length and willingness to handle admin will all influence which option suits you best. Some sectors favour contractors who operate through umbrella or limited companies, while others are comfortable working with sole traders.

It also helps to look beyond common assumptions. Choosing to open a limited company, for instance, won’t always increase your earnings, particularly if the contract falls inside IR35 or the

running costs erode the benefits. The better question is which structure leaves you in the strongest position once tax, compliance, administration and support are taken into account.

Comparing UK Working Structures

Switching Between Work Structures

Your working structure does not have to be the same for every contract. Some contractors start with an umbrella company, then move to a limited company when they secure suitable outside IR35 work. Others keep their limited company but use an umbrella company for assignments where PAYE is the better fit.

You may also use different structures simultaneously, depending on your contracts. For example, one assignment may be handled through an umbrella company, while another is managed through your limited company. What matters is that each contract is set up correctly, with the right tax treatment, paperwork, and support in place.

Planning is important. Contract start dates, payroll cut-offs, company setup, accounting requirements, and existing obligations can all affect how smoothly the change works. Before switching or combining structures, ask whether you are making a short-term decision for one contract or changing how you want to work long term.

Get Support Choosing the Right Structure

At Brookson, we’ve helped thousands of contractors choose the right working structure for their circumstances and preferences. We also have 30+ years of experience supporting them in setting up and running their businesses, however they choose to structure them.

That could mean providing umbrella employment, CIS support, accountancy for contractor businesses, or other tailored services based on the work you do. We can help you with:

• IR35 guidance to help you understand your contract position
• Setup and switching support when your working structure changes
• Managing ongoing admin and ensuring you stay on top of your responsibilities
• Legal, financial and insurance support in one place

Need support choosing a working structure or running your contractor business? Speak to one of our specialists and we’ll point you in the right direction.

Get in Touch >

FAQs

1. What’s the difference between an umbrella company and a limited company?

An umbrella company employs you and pays you through PAYE, while a limited company is a business you own and run. With an umbrella company, payroll and tax administration are handled for you. With a limited company, you have more control, but you are responsible for the company’s accounts, tax and filing obligations.

2. What’s the best working structure for UK contractors?

There is no single best working structure for every UK contractor. The right option depends on your contract, IR35 position and admin appetite, as well as how much control you want over your contracting business.

3. Which working structure gives contractors the highest take-home pay?

No structure automatically gives contractors the highest take-home pay. A limited company may offer more planning options for outside IR35 work, but tax treatment, provider fees, company costs and admin time can all affect what you actually keep.

4. Does IR35 apply to sole traders, umbrella workers, and limited company contractors?

IR35 is most relevant when you work through an intermediary, such as your own limited company. Umbrella workers are already paid through PAYE, while sole traders are not usually assessed under IR35 in the same way, although their work still needs to reflect genuine self-employment.

5. Can I use an umbrella company for one contract and a limited company for another?

Yes, you can use different structures for different contracts. For example, you might use an umbrella company for an inside IR35 assignment and your limited company for suitable outside IR35 work, provided each contract is set up and managed correctly.

6. How does CIS affect the way I work and get paid?

If your work falls under CIS, the contractor paying you is usually responsible for deducting tax before paying you and sending it to HMRC. You may receive less money upfront, but those deductions count towards your tax bill.