A complete guide for UK charity trustees on CT600 filing requirements, taxable income, and HMRC compliance
Many charity trustees are confused about the HMRC rules around charity Corporation Tax returns and the CT600 filing requirements. This confusion has increased following the changes introduced from 01 April 2026, where HMRC removed its free online service for charities to submit simple or nil Corporation Tax returns.
Good news: Most UK charities do not normally pay Corporation Tax and do not routinely need to file a CT600 Corporation Tax return. However, there are situations where a charity must submit a return to HMRC, even if no tax is due.
This guide explains when charities must file a CT600 Corporation Tax return, what counts as taxable income for charities, the new HMRC online filing rules from 01/04/2026, charity trading and Corporation Tax exemptions, CT600 filing deadlines and penalties, and frequently asked questions about charity Corporation Tax rules.
This article is written for UK charity trustees, charity managers, charitable companies, CIOs, small charities, volunteer run charities, and nonprofit organisations.
A CT600 is the official HMRC Corporation Tax return used by companies and charitable companies to report taxable income, gains, and Corporation Tax liabilities.
Most registered charities benefit from charity tax exemptions (HMRC guidance). Because of this, many charities do not need to pay Corporation Tax.
Important: Even if no tax is payable, HMRC can still legally require a charity to submit a CT600 return.
No. Most UK charities do not routinely file Corporation Tax returns.
A charity only normally needs to file a CT600 return if:
HMRC may issue a formal notice called a "Notice to Deliver a Company Tax Return (HMRC guidance)", commonly known as a CT603 notice.
If HMRC issues this notice, the charity must file a Corporation Tax return by the deadline, even if:
A charity may need to file a CT600 return if it has:
In practice, many small charities remain fully exempt because their activities fall within HMRC charity tax exemptions.
Charities could submit a simple or nil Corporation Tax return directly through HMRC's online service.
That service has now closed. If a charity must file a Corporation Tax return, it normally must:
There is no longer a free HMRC online CT600 filing option for most charities.
This change has caused difficulties for many volunteer run charities and small charitable organisations that previously relied on HMRC's free online filing service. If you need help with CT600 filing, contact our team.
HMRC may allow paper filing in limited circumstances, but this is uncommon.
Note: Most charities required to file a CT600 will now need to file electronically using approved software.
Many forms of charity income are exempt from Corporation Tax when applied for charitable purposes. However, some income may still become taxable.
A charity may need to file a CT600 return where it receives:
The rules are complex and depend on the charity's structure, activities, and how the income is used. Read HMRC's guidance on charity trading and taxation.
Primary purpose trading is trading activity that directly supports or advances the charity's charitable aims and objectives.
This type of income is generally exempt from Corporation Tax.
Non primary purpose trading refers to commercial or fundraising activity not directly connected to the charity's aims.
This income may become taxable if it exceeds exemption limits.
HMRC allows charities to carry out limited non primary purpose trading without paying Corporation Tax, provided turnover remains below the exemption thresholds. If trading exceeds these limits, some or all profits may become taxable.
The thresholds depend on the charity's overall income and circumstances. Read the full HMRC guidance on charity trading exemptions.
Tip: Because charity tax rules can be complex, trustees should seek professional advice where trading activities increase.
Yes. A charity is allowed to make profits provided:
Making a surplus does not automatically create a Corporation Tax liability.
The CT600 return must normally be filed:
12 months
after the end of the accounting period
If Corporation Tax is payable:
9 months + 1 day
after the accounting period ends
Important: Even where no tax is due, late filing penalties can still apply. Read HMRC's guidance on Corporation Tax penalties.
HMRC may issue penalties if a CT600 return is submitted late, even if no Corporation Tax is payable. This applies even to volunteer run charities or those with very small income.
Yes. A charity can appeal late filing penalties. HMRC may consider factors such as:
Many trustees report that HMRC can be helpful and understanding where charities engage with them promptly and honestly.
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Most UK charities do not normally pay Corporation Tax or routinely file CT600 returns. However, trustees should not ignore HMRC correspondence, especially CT603 notices.
The changes introduced from 01/04/2026 mean that charities required to file Corporation Tax returns will usually need commercial software or professional support to comply with HMRC requirements.
Trustees should monitor charity trading activities carefully and seek professional advice where there is uncertainty about taxable income, exemptions, or filing obligations.
For many charities, early advice can prevent penalties, reduce stress, and ensure full HMRC compliance.
We can help you understand your CT600 filing obligations, navigate the new HMRC requirements, and ensure your charity remains compliant. Our team specialises in charity accounting and tax matters.