Do I Need an Accountant for Corporation Tax? When DIY Makes Sense

It's one of the most common questions new limited company directors ask: do I actually need an accountant to handle my corporation tax?

The short answer: it depends on your company's complexity. For many small, straightforward limited companies, filing your own CT600 is perfectly doable — and could save you hundreds of pounds a year. But for others, an accountant's expertise is genuinely worth the money.

This guide helps you figure out which camp you're in.

What "Corporation Tax" Actually Involves

When people say "corporation tax," they usually mean the whole package:

Preparing your company accounts (profit & loss, balance sheet)
Computing your corporation tax (applying the right rate, reliefs, and allowances)
Filing your CT600 (the company tax return) with HMRC
Filing your accounts with Companies House
Paying the tax you owe

An accountant typically handles steps 1–4. But with modern software, you can handle these yourself — if your company is simple enough.

When DIY Makes Sense ✅

You're a good candidate for filing your own corporation tax if:

You're a Micro-Entity

Your company qualifies as a micro-entity if it meets at least two of these criteria:

Turnover of £632,000 or less
Balance sheet total of £316,000 or less
10 employees or fewer

Most sole-director limited companies — freelancers, contractors, consultants, small traders — comfortably qualify. Micro-entities can file simplified FRS 105 accounts, which are much easier to prepare.

Your Income Is Straightforward

If your company's income comes from one or two sources (e.g., client invoices, one line of business), and your expenses are standard business costs (software, equipment, travel, office supplies), your accounts are probably simple enough to prepare yourself.

You Have No Complex Tax Situations

DIY is realistic when you don't have:

R&D tax relief claims
Overseas income or foreign tax credits
Capital gains on significant assets
Group company structures or associated companies
Employee share schemes
Significant intercompany transactions
Previous-year losses you want to carry forward or back (though simple loss claims are manageable)

You're Comfortable with Basic Record-Keeping

You don't need to be an accountant, but you do need accurate records of your income and expenses. If you keep a simple spreadsheet or use basic bookkeeping software, you've got what you need.

When You Should Use an Accountant ❌

Seriously consider an accountant if:

Your turnover exceeds £632,000 — you'll need more detailed accounts (FRS 102) that require accounting expertise
You have multiple directors or shareholders — dividends, salary splits, and benefit-in-kind calculations get complex
You're claiming R&D tax relief — these claims are technical and HMRC scrutinises them closely
You have overseas income — foreign tax credits and double taxation treaties require specialist knowledge
You're unsure about capital allowances — an accountant can identify claims you might miss (Annual Investment Allowance, structures and buildings, etc.)
You've received an HMRC enquiry — professional representation is important
You want proactive tax planning — an accountant can advise on the most tax-efficient way to extract profits

The Real Cost Comparison

Approach	Typical Annual Cost
Accountant (small ltd company)	£300–£800
Accountant (complex affairs)	£800–£2,000+
DIY with Taxpipe	£59
DIY with other software	£80–£200

For a micro-entity with simple affairs, the difference between an accountant and DIY could be £250–£750 per year. Over five years, that's £1,250–£3,750.

What If I Get It Wrong?

This is the fear that keeps many directors paying for accountants — but it's worth putting in perspective:

HMRC charges penalties for late filing, not for honest mistakes. If you file on time and make a genuine error, you can submit an amended CT600 within 12 months.
Modern filing software validates your return before submission. Tools like Taxpipe check for common errors and inconsistencies automatically.
You can always get help later. Many directors file their own CT600 for straightforward years and bring in an accountant when things get complex.

That said, if you're genuinely unsure about a specific tax treatment (e.g., whether something counts as a capital allowance or an expense), it's worth paying for a one-off consultation rather than guessing.

The Middle Ground: DIY + Occasional Advice

Many directors find the sweet spot is:

File their CT600 themselves using software like Taxpipe (handling the routine annual filing)
Consult an accountant occasionally for specific questions (one-off consultations are typically £50–£150/hour)

This gives you the cost savings of DIY with the safety net of professional advice when you need it.

Making the Decision

Ask yourself these three questions:

Is my company a micro-entity with simple affairs? → DIY is realistic
Do I have any of the complex situations listed above? → Consider an accountant
Am I comfortable following a guided process with software? → You'll be fine filing yourself

If you answered yes to #1 and #3, and no to #2, you can confidently file your own corporation tax return and save yourself hundreds of pounds.

Taxpipe makes filing your CT600 simple — even with no accounting experience. Start your filing for £59 → — step-by-step guidance, automatic iXBRL generation, and direct submission to HMRC.

Do I Need an Accountant for Corporation Tax? When DIY Makes Sense