Partnership Accountant: Do You Need One?

A partnership accountant can prepare the SA800 partnership tax return, the partnership accounts and every partner’s own return. Partners can file the SA800 themselves instead, online through commercial software or on paper. Whether an accountant is worth paying for depends on the workload: more partners and records that need catching up both add to it.

The catch is that hiring one doesn’t hand over the responsibility. The figures stay the partners’, and HMRC doesn’t regulate tax agents, so anyone can call themselves one and the checking falls to you.

This guide is for ordinary partnerships where every partner is a person. If a company is one of the partners, the filing deadlines aren’t the same, so check the dates in HMRC’s notes before you file. For everyone else, the 2025/26 return is due online by 31 January 2027, or later if HMRC’s notice to file came after 31 July 2026.

The answer can turn on how profit is split between you and whether you’re happy filing through commercial software rather than paying a partnership accountant.

A partnership accountant files, but you stay responsible

Here’s what one accountancy firm says its standard partnership packages usually include:

• The accountant prepares the annual partnership accounts.
• The accountant submits the SA800 for the partnership.
• The accountant files each partner’s own Self Assessment return.
• The accountant works out how profit is allocated between the partners.

VAT returns, payroll and management reports sit outside that package as add-ons.

Sending the partnership tax return is the nominated partner’s job, even when an accountant prepares it. The same goes for each partner’s own return when an accountant for partnerships takes over the paperwork.

HMRC’s guidance on choosing an agent makes the same point about the figures themselves: they’re yours, even when an agent prepared them.

You shouldn’t sign a blank return for someone else to complete, or hand over your HMRC sign-in details.

Even with an accountant doing the filing, a few jobs stay with the partners:

• The partners keep the business records the accounts are built from.
• The partners decide how profit is shared, unless they’re content with the legal default of equal shares.
• The partners read the finished return before it’s signed and sent.

HMRC’s agent guidance asks for that last check in particular.

One partnership tax return, plus one per partner

Partnership self assessment is a set of linked returns rather than a single form. The partnership sends one SA800 partnership tax return, and every partner sends their own.

The SA800 reports the business’s income, with extra pages for things like UK property, foreign income and disposals of chargeable assets. Its partnership statement then allocates the profit, losses and other income between the partners. The short version of that statement only has space for three partners.

Each partner copies their share onto the SA104 partnership pages of their own Self Assessment tax return. These partnership supplementary pages come in two versions.

The short SA104S suits partners declaring nothing but partnership trading income and taxed interest or alternative finance receipts from a bank or building society, and the full SA104F covers every type of partnership income for partners who don’t qualify for the short pages.

Each partner’s tax bill is worked out on their own slice of the profit, and that’s the limit of what they owe on it. A new partnership has an extra step first: the nominated partner has to register a partnership with HMRC by 5 October in the business’s second tax year, and the other partners register separately.

Partnership profit sharing decides each partner’s tax bill

The Partnership Act 1890 sets the default rule. Unless the partners have agreed otherwise, whether in writing or by an implied understanding, they share profits equally and bear losses equally.

Under that default, no partner gets a salary or interest on the capital they put in. Those only exist if the partners agree them.

Here’s how much the split can matter. Asha and Ben’s partnership makes £72,000 profit in the 2025/26 tax year, and their agreement splits it 60:40:

• Asha is taxed on £43,200 and Ben on £28,800 under the agreement.
• Without any agreement, the equal-share default gives each of them £36,000.
• Switching between the two moves £7,200 of taxable profit from one partner to the other.

The partnership statement is where that split is recorded for HMRC.

Partnership tax return penalties land on every partner

For the 2025/26 tax year, the partnership tax return deadline is 31 January 2027 online or 31 October 2026 for a paper return, according to HMRC’s 2026 guide notes. You may get longer if HMRC sent the notice to file after 31 July 2026.

Late filing is where the per-partner rule bites. Where HMRC has issued a notice to file, it charges each person who was a partner during the return period:

• A £100 penalty applies once the return is late.
• After three months, £10 a day is added for up to 90 days, a maximum of £900.
• After six months, a further £300 is charged.
• After twelve months, another £300 is charged.

Three partners who send their 2025/26 return online on 31 March 2027 are two months late. That’s inside the three-month mark, so each pays £100, which comes to £300 between them.

Appeals go through the nominated partner (or their successor) alone, and one appeal speaks for all the partners. Having a reasonable excuse lets you appeal.

Paying late is a separate matter. Each partner’s Self Assessment bill is due by 31 January, and HMRC charges interest on tax paid late.

Doing it yourself means commercial software or paper

Partners can send the SA800 themselves, without an accountant, by either of two routes:

• Online filing needs two things: a registration for HMRC’s online service and a commercial software package bought separately.
• Paper filing brings the deadline forward to 31 October.

The software is the part to plan for, because it’s what HMRC’s notes point online filers to.

Doing it yourselves means covering the same ground an accountant would:

• The partners prepare the figures for the partnership’s income and expenses.
• The nominated partner completes the SA800 and its partnership statement, allocating each item of profit to the partners.
• The nominated partner sends the SA800 by the online or paper deadline.
• Each partner adds their share to their own return on the SA104 pages.

The real choice is whether the partners have the time and confidence for them, and what an accountant would charge instead.

Partnership bookkeeping comes with either route. Records have to be kept for at least five years after the 31 January deadline, so the 2025/26 records need keeping until at least 31 January 2032.

Making Tax Digital is the change still to come. HMRC has confirmed partnerships will join Making Tax Digital for Income Tax at some point, and has said it will publish their timetable later.

The guide to making tax digital for partnerships covers what’s known so far.

Partnership accountant fees and the checks HMRC suggests

One firm that explains its pricing bases it on how complex the partnership is and which services you need, and sells fixed-fee packages. The details that push a quote up are the ones that add work:

• Each partner’s own return can be charged per partner.
• VAT returns, payroll and partnership bookkeeping are sold as extras.
• Catching up on earlier years that were never finished can cost more.

Partnership accountant fees only compare fairly once you know what each quote includes.

There’s a silver lining, too. Accountancy fees can count as an allowable business expense when they’re for business reasons, so part of the bill comes back as lower tax.

Take a two-partner garden design business, with both partners living outside Scotland and no other income. The partnership makes £64,000 profit in 2026/27, split equally, and pays a partnership accountant £1,500 a year for bookkeeping and the partnership accounts.

Claimed as an expense, the fee cuts the partnership’s profit to £62,500, so each partner’s share falls from £32,000 to £31,250.

Each partner’s income tax drops by £150 at the 20% basic rate, and their Class 4 National Insurance drops by £45 at 6%. That’s £390 back between them, so the fee really costs the partners £1,110.

There’s one exception to watch. The rules on claiming legal and financial costs rule out what it costs to get your Self Assessment return prepared and sent.

That’s why the fee in the example covers bookkeeping and the accounts only: a per-partner charge for each partner’s own return wouldn’t come off the profit.

HMRC’s guidance on choosing a tax agent suggests these checks before you sign:

• Ask what they charge, how and when you pay, and what the contract commits you to.
• Check they have experience with businesses of your type and size.
• Check whether they belong to an accountancy or tax professional body.
• Ask whether they’re registered for online access with HMRC and meet its standards for agents.

It also suggests contacting more than one firm and meeting the person who’ll deal with HMRC for you. A partnership tax return accountant who passes those checks still needs you to review the return before it’s signed.

Deciding on a partnership accountant: your next step

A partnership accountant takes on the paperwork: the SA800, each partner’s own return and the profit split that links them. The figures, the deadlines and the per-partner penalties stay with the partners, whichever route you choose.

Doing it yourselves is possible online through commercial software, or on paper, as long as the records are kept and the profit split is clear. What changes between the routes is who does the work and what it costs.

If you’d rather hand it over, run HMRC’s checks above before signing anything, and the page on how to find an accountant explains the search options. Either way, check the dates for your tax year in HMRC’s notes before you file.

Key Takeaways

• A partnership accountant can prepare the SA800, the partnership accounts and each partner’s return, but the figures stay the partners’ responsibility.
• The nominated partner sends the partnership tax return, and every partner also sends an individual Self Assessment return.
• With no agreement, written or implied, the Partnership Act 1890 splits profit equally between partners.
• For 2025/26, the SA800 is due by 31 January 2027 online or 31 October 2026 on paper, with later dates in some cases.
• Once HMRC has issued a notice to file, a late partnership return costs each partner £100, with further daily and fixed penalties after three, six and twelve months.
• HMRC doesn’t regulate tax agents and suggests checking fees, experience, professional body membership and HMRC registration before hiring one.