How to Pay Corporation Tax to HMRC: Methods and Deadlines

Corporation Tax is not paid at the same time a company files its Company Tax Return. That single detail catches out a surprising number of UK companies, especially smaller limited companies where the director is also handling bookkeeping, payroll approvals, VAT returns and cash flow decisions.

HMRC expects the tax to be paid before the Corporation Tax return filing deadline for most companies. The payment is normally due 9 months and 1 day after the end of the company’s accounting period, while the CT600 Company Tax Return is usually due 12 months after the end of the accounting period. The separation between payment and filing is where many practical problems begin.

Paying Corporation Tax to HMRC is not difficult in a technical sense. The harder part is knowing the correct deadline, using the right payment reference, allowing enough time for the payment method, and making sure the figure being paid is based on reliable accounts rather than a late estimate pulled together under pressure. Where the calculation itself is uncertain, wider Corporation Tax support may be relevant before the company commits to a payment figure.

The Corporation Tax payment deadline is earlier than many directors expect

For a company with a 31 March year end, Corporation Tax is usually payable by 1 January following the end of that accounting period. The Company Tax Return is normally due by 31 March. In practice, this means a company often needs to know its Corporation Tax liability three months before the final filing deadline.

This creates an operational issue. If bookkeeping is behind, bank reconciliations are incomplete, VAT control accounts are not reviewed, payroll journals are missing, or director loan account movements have not been checked, the company may not have a reliable Corporation Tax figure by the payment deadline.

HMRC does not generally wait for the CT600 filing deadline before expecting payment. If the tax is paid late, interest can be charged from the day after the due date. Filing the return on time does not remove late payment interest if the Corporation Tax itself was paid late.

How most limited companies pay Corporation Tax

HMRC accepts several payment methods for Corporation Tax. The right method usually depends on how close the company is to the deadline, how the business manages authorisations, and whether the payment is being made from a UK bank account.

Online or telephone banking using Faster Payments, CHAPS or Bacs

For most UK companies, online banking is the most practical way to pay Corporation Tax. Payments can usually be made by Faster Payments, CHAPS or Bacs, depending on the bank and the company’s payment limits.

Faster Payments are often received quickly, sometimes the same day, but directors should not assume this will always happen instantly. Bank security checks, payment limits, dual authorisation rules and weekend processing can all create friction.

CHAPS can be useful for larger payments or urgent same-day settlement, though banks may charge a fee. Bacs normally takes longer and is rarely ideal where the deadline is close.

The payment must be made to the correct HMRC Corporation Tax bank account and must include the correct reference. HMRC’s bank details and payment guidance should always be checked directly before making payment, as using outdated saved payee details is an avoidable risk.

Direct Debit

Companies can pay Corporation Tax by Direct Debit, but it is not always the best option for last-minute payments. A first Direct Debit can take several working days to set up, and subsequent payments also need processing time.

Direct Debit may suit companies that plan ahead and want a controlled payment process. It is less suitable where the tax figure is only finalised shortly before the due date.

Debit card or corporate credit card

HMRC allows some online card payments, although rules, fees and card acceptance can vary. Personal credit cards are generally not accepted for tax payments. Corporate cards may involve charges.

Card payments can be convenient, but they should not become a substitute for tax cash flow planning. A company that regularly needs card facilities to meet Corporation Tax liabilities may have a broader working capital issue that should be examined through management accounts or cash flow forecasting.

At a bank or building society

Some companies may still be able to pay at a bank or building society using HMRC payment documentation, but this is less common in modern practice and depends on the availability of the correct payslip and banking arrangements.

For most companies, digital payment routes are more predictable. The key is to make the payment early enough that processing time does not become the deciding factor.

The payment reference matters more than directors often realise

HMRC identifies Corporation Tax payments using a specific reference, usually linked to the company’s Corporation Tax Unique Taxpayer Reference and the accounting period being paid. This is not the same as the company registration number, VAT number, PAYE reference or personal Self Assessment UTR.

Using the wrong reference can result in the payment sitting uncleared, being allocated to the wrong period, or not appearing against the expected Corporation Tax liability. The company may then receive payment reminders even though money has already left the bank account.

That situation is frustrating, but it is also administratively expensive. Someone has to trace the payment, speak to HMRC, provide bank evidence, and wait for the allocation to be corrected. During that period, HMRC systems may still show the amount as outstanding.

Before payment is made, companies should check:

• the Corporation Tax reference relates to the correct company;
• the accounting period shown by HMRC matches the period being paid;
• the payment amount agrees to the latest tax computation;
• the bank account used belongs to the company, unless there is a clear reason otherwise;
• the payment date allows for the chosen method’s processing time.

How to work out the amount to pay

The amount due is not simply a percentage of money in the bank or turnover for the year. Corporation Tax is calculated on taxable profits after accounting adjustments, allowable expenses, capital allowances, disallowable items, losses, reliefs and any relevant associated company considerations.

For smaller companies, the final liability may be affected by issues such as director remuneration, pension contributions, capital purchases, bad debt provisions, entertaining costs, use of home claims, company cars, loan relationships, or prior-year losses. These are not payment mechanics, but they directly affect the figure being paid.

The practical problem is timing. If accounts are prepared only shortly before the CT600 deadline, the company may already have missed the Corporation Tax payment deadline. Sensible companies therefore aim to prepare at least a reasonably reliable tax estimate before the payment due date, then refine the final return later if needed.

Where the final Corporation Tax liability is uncertain, paying a prudent estimate before the deadline can reduce interest exposure. Overpayments can usually be repaid or offset, but deliberately careless estimates create their own risks. The better approach is to maintain records throughout the year so the estimate is not a guess.

Accounting period changes can alter the deadline

Corporation Tax deadlines become less straightforward when the company changes its accounting period, prepares accounts for a period longer than 12 months, or has recently incorporated.

Companies House accounts and Corporation Tax accounting periods do not always behave in exactly the same way. A company may file one set of statutory accounts covering a longer first period, but HMRC may require more than one Corporation Tax return because a Corporation Tax accounting period cannot normally exceed 12 months.

This can create multiple payment deadlines and multiple CT600 filings. A new company with an extended first accounting period should not assume that one Companies House filing deadline means one Corporation Tax deadline. HMRC’s Corporation Tax records should be checked carefully, particularly after incorporation, dormancy changes or accounting reference date changes.

Large companies and quarterly instalment payments

Most small and medium-sized companies pay Corporation Tax 9 months and 1 day after the accounting period end. Larger companies may be required to pay by quarterly instalments, which brings tax payments forward significantly.

The quarterly instalment rules are more complex than the standard deadline and can apply based on taxable profits and associated company rules. Groups, companies with rapid profit growth, and businesses that have recently crossed size thresholds should be cautious about assuming the usual payment deadline still applies.

The risk is not just a missed payment. Quarterly instalments require forecasting discipline because payments may be due before the final profit figure is known. That changes the finance function’s role: tax becomes part of in-year financial management rather than a year-end compliance task.

What happens if Corporation Tax is paid late

If Corporation Tax is paid late, HMRC can charge interest from the day after the due date until the payment is received. Late payment interest is not the same as a late filing penalty. A company can file its CT600 on time and still owe interest if the tax was paid after the payment deadline.

Late filing penalties may apply separately if the Company Tax Return is submitted after its due date. In more serious cases, repeated non-compliance can attract closer HMRC attention, especially where returns, VAT payments, PAYE liabilities and Corporation Tax are all falling behind.

Late payment can also create practical business consequences beyond HMRC interest. It may distort cash flow forecasts, delay dividend decisions, complicate director loan account planning, and reduce confidence in management information. For companies seeking finance, inconsistent tax compliance may raise questions during due diligence.

Common payment mistakes that create unnecessary problems

Most Corporation Tax payment issues are not caused by obscure tax law. They usually come from process failures: the wrong reference, the wrong deadline, an unreconciled estimate, or an assumption that someone else has handled it.

Typical mistakes include:

• confusing the Corporation Tax payment deadline with the CT600 filing deadline;
• using the company registration number instead of the Corporation Tax payment reference;
• paying HMRC PAYE or VAT bank details by mistake;
• forgetting that weekends and bank holidays can affect payment planning;
• assuming HMRC has received a payment because it left the company bank account;
• leaving accounts preparation too late to calculate a reliable liability;
• failing to update forecasts after a profitable year;
• paying from a director’s personal account without keeping clear evidence;
• overlooking quarterly instalment rules after growth or group restructuring.

These errors are avoidable, but only if Corporation Tax is treated as a workflow rather than a single payment event.

The link between bookkeeping quality and paying the right amount

A company cannot reliably pay the right Corporation Tax if its underlying records are weak. Bank feeds may be connected, invoices may be stored, and accounting software may produce a profit figure, but that does not automatically mean the tax position is correct.

Common bookkeeping issues that affect Corporation Tax include unreconciled suspense accounts, duplicated expenses, missing sales invoices, personal costs posted to company expenses, incorrect VAT treatment, payroll journals not posted, and fixed asset purchases coded directly to profit and loss.

VAT and payroll do not sit outside Corporation Tax. VAT errors may affect turnover, expenses and balance sheet liabilities. Payroll errors can affect deductible salary costs, PAYE liabilities and director remuneration planning. CIS deductions, if relevant, may also affect the company’s cash position and HMRC account reconciliations.

For owner-managed companies, the director loan account is another frequent source of difficulty. Personal spending through the company, informal withdrawals, dividends voted without sufficient profit, or incomplete records can all change the year-end tax picture. Corporation Tax payment planning is much easier when these issues are reviewed before the deadline rather than after it.

A practical payment workflow for UK companies

The best Corporation Tax payment process is usually simple, but it needs to start early. A sensible workflow might look like this.

• Shortly after the year end: complete bank reconciliations, review sales and purchase ledgers, and identify missing documents.
• Before the payment deadline: prepare draft accounts or a reliable tax estimate, including major adjustments and reliefs.
• At least several working days before payment: confirm HMRC’s current payment details, the correct reference and the payment method.
• On payment: retain evidence from the bank showing date, amount, account and reference used.
• After payment: check HMRC’s online account once updated and reconcile the payment in the bookkeeping system.
• Before CT600 filing: finalise the Corporation Tax computation and deal with any balancing payment or overpayment.

This workflow is not elaborate. Its value is that it reduces dependence on memory, inbox searches and deadline panic. It also makes responsibilities clearer where directors, bookkeepers, accountants and internal finance staff all touch different parts of the process. For companies reviewing the wider submission timetable, corporate tax filing context can help separate calculation, payment and filing responsibilities.

Real-world scenarios where Corporation Tax payment becomes complicated

A company with steady profits, clean bookkeeping and a standard year end may find Corporation Tax payment straightforward. Complexity tends to appear when the business changes.

A growing consultancy may have a highly profitable year after hiring staff late in the period. The bank balance looks healthy, but PAYE, VAT and Corporation Tax liabilities are all building at once. If the director treats the full bank balance as available cash, the Corporation Tax payment can become a surprise rather than a planned liability. This is where corporate tax planning becomes less about theory and more about cash-flow discipline.

A construction company operating under CIS may have tax deducted at source, subcontractor costs, VAT reverse charge entries and payroll obligations all interacting with HMRC accounts. Payment planning requires more than looking at headline profit.

A new company may assume it has nothing to do until Companies House asks for accounts. By the time the director focuses on statutory accounts, the first Corporation Tax payment deadline may already be close, and the accounting period may need more careful handling than expected.

A company that has made losses in previous years may expect no Corporation Tax, but a current-year profit, restrictions on loss use, or changes in trade can alter the position. Past losses are useful only if they are correctly recorded, available and applied in accordance with the rules.

How Corporation Tax payment affects dividends and director decisions

Corporation Tax is closely linked to dividend planning. Dividends are paid from distributable profits after considering the company’s financial position. A company that has not allowed for its Corporation Tax liability may overestimate how much profit is available for dividends.

This matters for owner-managed companies. A director may see cash in the bank and take dividends, only to find later that the company needed part of that cash for Corporation Tax, VAT or PAYE. If dividends are paid without sufficient distributable reserves, the accounting and tax consequences can become awkward.

Some owner-managed businesses also have personal tax and business tax responsibilities running in parallel, particularly where the director receives dividends, salary or other income. That is separate from the company’s Corporation Tax position, but it can overlap in cash-flow planning and record keeping. For non-company business structures, small business tax returns follow different rules from limited company Corporation Tax.

Good payment planning therefore supports better director decisions. It helps distinguish between cash that belongs to the business, cash needed for tax, and cash potentially available for extraction or reinvestment.

Checking whether HMRC has received the payment

After paying Corporation Tax, companies should allow time for HMRC systems to update. The payment may not appear immediately, even where the bank transfer has been made correctly.

If a payment does not show after a reasonable period, the first step is to check the bank evidence and the reference used. HMRC may need the payment date, amount, sort code, account details, reference and confirmation that the payment left the bank account.

Directors should not ignore HMRC reminders simply because they believe payment was made. A reminder may indicate a timing delay, but it may also indicate a reference error or allocation problem. Early investigation is usually easier than trying to unwind several months of correspondence later.

Record keeping: what to retain after payment

Corporation Tax payment evidence should be retained with the company’s tax records. At minimum, the company should keep evidence of the payment instruction, bank statement entry, HMRC reference used, tax computation supporting the amount, and any HMRC correspondence about allocation or repayment.

These records are useful for year-end accounts, CT600 preparation, audit trails, HMRC enquiries, finance applications and internal governance. They also help future accountants understand what happened without relying on a director’s memory.

Record keeping is particularly important where payment is made from an account that is not the company’s main bank account, where a director pays personally on behalf of the company, or where a group company makes payment centrally.

Paying too much or too little

If a company underpays Corporation Tax, HMRC may charge interest on the unpaid amount. If the underpayment is discovered before filing, the company can usually make an additional payment. If it is discovered after filing, the return may need to be amended depending on the circumstances.

If the company overpays, the excess can often be repaid or offset against other liabilities. However, overpaying should not be used as a substitute for proper tax calculation. It can tie up cash unnecessarily, and for some businesses that cash may be needed for wages, suppliers, VAT, loan repayments or working capital.

The better discipline is to produce reliable management information early enough to pay a well-supported amount. Precision improves when bookkeeping, accounts preparation and tax review are not treated as separate, disconnected exercises.

Corporation Tax payment as a management issue, not just a tax task

For small companies, Corporation Tax often becomes visible only once a year. For better-run companies, it is visible throughout the year as part of profit monitoring and cash flow management.

This distinction matters. A company that tracks taxable profit during the year can plan reserves, avoid excessive drawings, assess dividend capacity, and anticipate HMRC liabilities. A company that waits until after the year end may still comply, but it has less room to make informed decisions.

Quarterly management accounts, even in a simple form, can make Corporation Tax less disruptive. They do not need to be over-engineered. They need to be accurate enough to show whether profit is building, whether tax reserves are realistic, and whether cash is being consumed by working capital rather than available profit.

Key takeaways for paying Corporation Tax to HMRC

• Most companies must pay Corporation Tax 9 months and 1 day after the end of the accounting period.
• The CT600 filing deadline is usually later, so filing on time does not guarantee payment was on time.
• The correct HMRC payment reference for the relevant accounting period is essential for allocation.
• Online banking is often the most practical method, but processing times, bank cut-off times and authorisations must be allowed for.
• Companies with larger profits may need to consider quarterly instalment payments.
• Bookkeeping quality directly affects the reliability of the amount paid.
• VAT, payroll, CIS, director loan accounts and dividends can all influence Corporation Tax planning in practice.
• Payment evidence should be retained and reconciled after HMRC has processed it.

A more useful way to think about the deadline

The Corporation Tax deadline is not merely a date in the diary. It is a test of whether the company’s accounting records, tax estimates and cash planning are functioning properly.

Companies rarely get into difficulty because they do not know HMRC wants to be paid. They get into difficulty because the profit figure is unclear, the reference is wrong, the payment method takes longer than expected, or tax cash has already been absorbed by other decisions.

Paying Corporation Tax well means doing several modest things at the right time: keeping records clean, reviewing profit before the deadline, checking HMRC details, using the correct reference, and retaining evidence. None of these steps is dramatic. Together, they turn Corporation Tax from a stressful annual interruption into a controlled compliance process.