Sole Trader vs Partnership: Pros, Cons and Tax Basics
If you are going into business with someone else, you face a choice: stay sole traders who work together, form a partnership or set up a company. This guide compares being a sole trader with an ordinary partnership in the UK, covering liability, tax returns, profit sharing and the agreements that keep business friendships intact. It is general information, not tax or legal advice, and rates and rules change every tax year, so check GOV.UK or an accountant before you commit.
Key takeaways
- A sole trader runs a business alone; an ordinary partnership is two or more people sharing a business and its profits.
- In an ordinary partnership, partners are personally responsible for business debts, just like sole traders.
- A partnership has a nominated partner who registers it with HMRC, and the partnership files its own return.
- Each partner pays Income Tax and National Insurance on their own share of the profit through Self Assessment.
- A written partnership agreement is not always required, but it is one of the most valuable documents you can have.
Many small businesses start with two friends, a couple or two former colleagues deciding to work together. Sometimes they never think about structure at all, and only discover the questions when a client asks who to invoice, the bank asks who owns the account or HMRC asks for a return. Deciding early saves a lot of confusion later.
What each structure actually is
Sole trader
A sole trader is one self-employed person running a business as an individual. You make the decisions, keep the profit after tax and file one Self Assessment return. You must register for Self Assessment if you earn more than £1,000 from self-employment in a tax year, by 5 October after the end of the tax year in which you started.
Ordinary partnership
An ordinary partnership is two or more people running a business together and sharing the profits. It is not a separate legal entity in the way a company is. One partner, the nominated partner, registers the partnership with HMRC and is responsible for the partnership's tax return. Each partner also registers for Self Assessment and files a personal return showing their share of the profit.
There are other forms, such as limited liability partnerships (LLPs) and limited partnerships, which work differently. This guide focuses on the ordinary partnership, which is what most small two-person businesses mean when they say "partnership."
Common mistake
Assuming you are not in a partnership because you never signed anything. If you run a business together and share profits, you may be treated as partners anyway. If that is not what you want, set things up clearly, for example as two sole traders with separate clients and invoices, or as a company.
Liability: the point most people overlook
Sole traders have unlimited liability: they are personally responsible for the business's debts. Partners in an ordinary partnership are in the same position, with one important twist. You are not just responsible for your own decisions; you can be responsible for business debts your partner ran up on behalf of the partnership.
That makes trust and clear rules essential. Before you form a partnership, ask yourself:
- Do I trust this person's judgment with money and contracts?
- Who can sign contracts, order supplies or borrow money for the business?
- What happens if one of us wants to leave, falls ill or dies?
- How would we handle a large claim or an unpaid debt?
If those questions make you uncomfortable, two sole traders working together, or a limited company, might suit you better. Whatever you choose, look at insurance that matches the risks of your work.
How tax works in each case
For tax, both sole traders and partners are self-employed. You pay Income Tax and Class 4 National Insurance on your own profit, through your own Self Assessment return. The difference is how the profit is calculated and reported.
| Area | Sole trader | Ordinary partnership |
|---|---|---|
| Registering with HMRC | You register for Self Assessment | Nominated partner registers the partnership; each partner registers for Self Assessment |
| Returns filed | One personal return | A partnership return plus a personal return for each partner |
| Who pays tax | You, on all the profit | Each partner, on their share of profit |
| Liability | Unlimited, personal | Unlimited, personal, and partners can be responsible for each other's business debts |
| Decision making | You alone | Shared, ideally set out in an agreement |
| Accounting method | Cash basis by default | Cash basis by default for partnerships without corporate partners |
The rates are the same for sole traders and partners. For 2026/27 in England, Wales and Northern Ireland, the Personal Allowance is £12,570, the basic rate is 20% up to £50,270, the higher rate 40% up to £125,140 and the additional rate 45% above that. Scotland has different bands. Class 4 National Insurance is 6% on profits between £12,570 and £50,270 and 2% above.
Example
Imagine a partnership of two that makes £60,000 profit in a tax year and splits it equally. Each partner reports £30,000 on their personal return. In a simplified view that ignores other income, student loans and Scottish rates, each would pay 20% Income Tax and 6% Class 4 National Insurance on £17,430, the amount above £12,570. One sole trader earning the full £60,000 alone would have part of that profit taxed at the higher rate instead. The figures are made up for illustration only.
Splitting profit between partners can mean each uses their own Personal Allowance and basic rate band. But the split must reflect the real arrangement between the partners. Do not set up a partnership just to move income on paper; get advice if tax is the main motive.
Pros and cons of each
Sole trader strengths
- Full control over decisions and direction
- Only responsible for your own business debts
- One return, simplest admin
- Easy to start and easy to close
- No need to agree profit splits with anyone
Partnership strengths
- Shared workload, skills and contacts
- Shared startup and running costs
- Profit taxed in each partner's hands according to their share
- Still relatively simple compared with a company
- Cover when one partner is away or ill
The flip side of a partnership is shared liability, shared decisions and the risk of disputes. The flip side of being a sole trader is that everything, from sales to bookkeeping to holidays, depends on you.
What to put in a partnership agreement
A written partnership agreement sets out how the business works between you. It is far easier to agree these points while everyone is getting along. Consider covering:
- Profit and loss shares. How profit is split, and whether partners draw a fixed amount each month.
- Capital. What each partner puts in and how it is repaid if they leave.
- Roles and authority. Who does what, and which decisions need both partners to agree, such as borrowing or signing large contracts.
- Time commitment. Whether partners can do other work on the side.
- Leaving and joining. Notice periods, how a departing partner's share is valued and how new partners join.
- Disputes. A process for resolving disagreements before they become legal battles.
- Ending the partnership. What happens to clients, assets and the business name if you split up.
Pro tip
Have a solicitor review your partnership agreement, even if you start from a template. A small cost now can prevent a costly argument later, especially over who keeps the clients if you part ways.
Which one should you choose?
Choose to stay a sole trader if you want full control, your work does not depend on a co-owner, or you simply collaborate with others on projects. Two sole traders can share an office, refer work to each other and even work on joint projects, while each keeps their own clients, invoices and tax return.
Consider a partnership if you genuinely want to own and run one business together, share profits and losses and present yourselves as one firm, and you are comfortable with shared liability. If the liability worries you, compare a limited company or an LLP with an accountant or solicitor.
Before you work with a partner
- Decide whether you are one business or two sole traders working together
- Discuss how profit, costs and decisions will be shared
- Agree who will be the nominated partner if you form a partnership
- Register the partnership and each partner for Self Assessment
- Put a written partnership agreement in place
- Open a bank account for the partnership
- Review insurance and how you would handle a large debt or claim
Frequently asked questions
Does a partnership pay tax itself?
An ordinary partnership files its own return with HMRC showing the profit and how it is split, but the tax is paid by each partner on their share through their personal Self Assessment return.
Can partners split profit unequally?
Yes. Partners can agree any split that reflects their arrangement, such as different capital or time commitments. Set it out in your partnership agreement and make sure the partnership return matches it.
Can my spouse be my business partner?
Yes, spouses and civil partners can run a business as partners. The arrangement should be genuine, with both taking part in the business. If tax saving is the main aim, take advice first.
What happens if my partner leaves?
It depends on your agreement. Without one, the partnership may need to be dissolved. A good agreement explains how a departing partner's share is valued and paid, and whether the business can continue.
Related reading
The bottom line
Being a sole trader gives you control and simplicity, while a partnership lets you share the work, the profit and the risk with someone you trust. In both cases you are taxed as self-employed on your own profit and have personal liability for debts, so the decision is mostly about whether you truly want to run one business together and how well you have agreed the rules.
This is general information, not tax or legal advice. Tax rates, thresholds and rules change every tax year, so check the latest guidance on GOV.UK or with HMRC, and talk to an accountant or solicitor before you form a partnership.
