Corporation Tax repayment: how long it takes, how to claim

In short: HMRC publishes no standard processing time for a Corporation Tax repayment claimed on a Company Tax Return (CT600), but says bank details on every return speed it up (GOV.UK: Get a refund or interest on your Corporation Tax). HMRC's only published Corporation Tax repayment estimate covers loss carry-back claims sent by post: 5 November 2026 for a claim sent on 28 September 2026.

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How long does a Corporation Tax repayment take in 2026?

HMRC doesn't publish a standard time for repaying Corporation Tax claimed on a CT600. GOV.UK says only that giving bank details on every return means a repayment is processed more quickly (GOV.UK: Get a refund or interest on your Corporation Tax). The one Corporation Tax repayment estimate HMRC does publish covers loss carry-back claims sent by post, and on 28 September 2026 it was about five and a half weeks.

HMRC's "Check when you can expect a reply from HMRC" tool lists only two Corporation Tax items: complaints, and repayments due to a loss carry-back sent by post. HMRC says the tool is updated weekly (GOV.UK: Check when you can expect a reply from HMRC). We ran the tool on 28 September 2026 with a contact date of 28 September 2026. It answered that a reply could be expected by 5 November 2026, 38 days later, warned that the date is an estimate and may change, and said HMRC was then processing claims received on 14 August 2026. The tool has no entry for an ordinary refund claimed on an online CT600, so no official waiting time exists for that case, and any figure quoted elsewhere is not HMRC's. HMRC's Corporation Tax contact page adds that its peak period for Company Tax Returns runs from December to April (GOV.UK: Corporation Tax: general enquiries), which is worth allowing for if the company files in those months.

HMRC's internal manual describes how an online return that shows too much tax paid is normally handled. It calls the approach "process now, check later" and says it will usually lead to an immediate repayment of the excess tax paid (CTM92030). The rule behind the repayment is section 59D of the Taxes Management Act 1970. Corporation Tax is due on the day after the end of the 9 months following the accounting period, and if the amounts already paid for that period exceed the tax payable, "the excess shall be repaid" (TMA 1970 s59D). Neither source puts a number of days on the process. A complete return with bank details is therefore the quickest route the law and HMRC's guidance describe, but HMRC can still check a return and hold back a repayment while it does.

Some repayments can't arrive before a date fixed by law, however quickly HMRC works. A company can reclaim section 455 tax on a director's loan only from 9 months and 1 day after the end of the accounting period in which the loan was repaid, written off or released, and GOV.UK says the company will not be repaid before that date (GOV.UK: Director's loans: If you owe your company money). A trading loss normally can't be carried back until the loss-making period has ended. HMRC's manual explains that a company cannot usually anticipate losses to obtain a repayment, because a loss must first be set against the loss-making period's own profits before any remainder is carried back, and HMRC considers an earlier claim only in exceptional cases backed by full evidence (CTM92090).

When is a company due a Corporation Tax refund?

A company is due a Corporation Tax refund when HMRC holds more than the tax payable for a period. The usual causes are paying more than the finished return shows, carrying a trading loss back, reclaiming section 455 tax after a director repays a loan, or claiming a payable tax credit (GOV.UK: Get a refund or interest on your Corporation Tax).

The commonest case is an overpayment for the period itself. A company with taxable profits up to £1.5 million pays its Corporation Tax 9 months and 1 day after the accounting period ends, often before the accounts are final, and a company with profits over £1.5 million pays estimated instalments (GOV.UK: Pay your Corporation Tax bill: Overview). When the finished CT600 shows less tax than was paid, the excess is repayable, and the guide to paying Corporation Tax covers the payment side. A payment made in error is treated differently. A payment with the wrong reference can pay the wrong tax bill, and GOV.UK tells the company to contact Corporation Tax general enquiries to have it moved. HMRC's manual says repayment interest does not apply when HMRC Payments repays a payment made in error or allocated incorrectly (COM128001), so a mistaken payment earns nothing while HMRC holds it.

A trading loss carried back creates a repayment for an earlier period. GOV.UK lets a company set a trading loss against its profits of the previous 12 months, claimed in the Company Tax Return for the loss-making period within 2 years of that period's end, and says HMRC will send a repayment unless the company owes Corporation Tax, which is deducted first (GOV.UK: Work out and claim relief from Corporation Tax trading losses). The loss schedule guide explains the boxes. Section 455 tax works differently. A close company pays it on a loan to a director or other participator that is still outstanding 9 months after the year end, and can reclaim the tax, but not any interest charged on it, once the loan is repaid, written off or released (GOV.UK: Director's loans: If you owe your company money). The CT600A and section 455 guide explains when the charge arises and how the relief is shown.

Some payable tax credits also reach the company as repayments. HMRC's CT600 guide lists repayment boxes for income tax deducted from the company's income (box 870), payable research and development credits (boxes 875 and 880), creative industries credits (boxes 885 and 886), land remediation or life assurance company credits (box 890) and the capital allowances first-year tax credit (box 895) (HMRC's CT600 guide). Repayment interest on research and development, land remediation and other tax credits runs from the later of the return's filing deadline and the date the return containing the claim is delivered, while interest on income tax suffered at source runs from the day after the accounting period ends (CTM92310). Each credit has its own conditions and supplementary pages, so this list is an outline only.

How do you claim a Corporation Tax repayment on the CT600?

Claim a Corporation Tax repayment in the Company Tax Return itself. Tick box 40 to tell HMRC a repayment may be due for the period, and enter the company's bank or building society details in boxes 920 to 940 (HMRC's CT600 guide). HMRC then sets the tax on the return against the tax the company paid and repays the difference.

HMRC's CT600 guide sets out the bank details boxes. Box 920 takes the name of the bank or building society, box 925 the 6-digit sort code, box 930 the account number, box 935 the name of the account and box 940 any building society reference. HMRC asks for these details on every return, whether or not a repayment is expected, and for security reasons uses only the details from the latest return (HMRC's CT600 guide). A claim that reduces tax for an earlier period, such as a loss carry-back, is flagged in box 45 instead of box 40. If the company paid its tax by debit or credit card, HMRC's guide says the repayment will normally go back to that card instead of the bank account.

The amount boxes follow a fixed chain on HMRC's form. Box 595 records the Corporation Tax already paid for the period and not repaid, box 605 is the tax overpaid (boxes 545, 560, 565 and 595 minus box 525), and box 865 is the Corporation Tax to be repaid (box 605 minus boxes 570, 575 and 580) (HMRC's CT600 guide). Box 860 controls small repayments. HMRC repays an overpayment of more than £100 automatically, and one of £100 or less only when the return gives bank details; otherwise it sets the money against later accounting periods. A company can stop automatic repayments by entering a limit over £100 in box 860, and the limit must be renewed on each return. If a return has already gone in without the tick or the bank details, GOV.UK says amendments must usually be made within 12 months of the filing deadline, and overpayment relief may still be available after that (GOV.UK: Company Tax Returns: Making changes).

A company can also ask for a repayment outside the return in a few situations. Tax paid before the normal due date can be repaid up to that date without pre-conditions, and after the due date a company can apply under section 59DA of the Taxes Management Act 1970 by stating the amount it considers repayable and its grounds for believing it has paid too much (TMA 1970 s59DA). Section 455 relief can be claimed on the CT600A or, in the cases GOV.UK describes, with form L2P, which has an online service using a Government Gateway user ID (GOV.UK: Reclaim tax paid on loans to participators (L2P)). For an ordinary overpayment, GOV.UK's refund page tells companies to use the Company Tax Return to say a repayment is due and how they want it paid. HMRC's digital assistant answers questions about Corporation Tax repayments, and the Corporation Tax helpline is 0300 200 3410.

How much repayment interest does HMRC pay on overpaid Corporation Tax?

HMRC pays repayment interest at 2.75% a year, the rate since 9 January 2026, on overpaid Corporation Tax. It runs from the later of the due date and the date paid, until HMRC issues the repayment (GOV.UK: Get a refund or interest on your Corporation Tax). Tax paid early, including quarterly instalments that prove too high, earns credit interest at 3.50% up to the due date instead.

Both rates are set in legislation and linked to the Bank of England base rate. HMRC's rates page says repayment interest is base rate minus 1%, with a lower limit of 0.5%, and lists late payment interest on unpaid Corporation Tax at 7.75% from 9 January 2026 (HMRC interest rates). The same page gives one credit interest rate, 3.50% from 29 December 2025, for overpaid quarterly instalments and for early payments by companies that don't pay by instalments; after the normal due date, both kinds of company get repayment interest. Credit interest on early payments uses a smaller deduction, the reference rate minus 0.25, which is why it is higher than repayment interest (CTM92290). Credit interest cannot start earlier than 6 months and 13 days after the accounting period begins, and it stops at the normal due date. Repayment interest is taxable, and GOV.UK says to include it as income in the Company Tax Return.

Taxley's worked example (an illustration, not a real company): a company's accounting period runs from 1 April 2025 to 31 March 2026, so its Corporation Tax is due on 1 January 2027, 9 months and 1 day after the period ends (GOV.UK: Pay your Corporation Tax bill: Overview). The director pays an estimate of £12,000 on 1 January 2027 by Faster Payments; that day is a bank holiday, and GOV.UK says other payment methods must reach HMRC by the last working day before. The director then files the CT600 in March 2027 showing tax of £10,000, so the company has overpaid £2,000. On HMRC's form, box 525 would show £10,000 of tax payable, box 595 £12,000 already paid, and boxes 605 and 865 £2,000 overpaid and to be repaid. Repayment interest starts on 1 January 2027, the later of the due date and the payment date, and runs until HMRC issues the repayment. At 2.75% a year, £2,000 earns £55 a year: about £4.58 a month, or 15p a day (HMRC interest rates).

The repayment dates in the table are illustrations, not HMRC processing times, and the figures assume the rate stays at 2.75%, which changes whenever the base rate does (HMRC interest rates). If the director in the example had paid the same £12,000 early, on 1 October 2026, HMRC would usually pay credit interest at 3.50% from the payment date to the 1 January 2027 deadline (GOV.UK: Get a refund or interest on your Corporation Tax). Over those 92 days the whole £12,000 would earn about £105.86, of which about £17.64 relates to the £2,000 later found to be overpaid. Repayment interest on the £2,000 would still start on 1 January 2027, because it runs from the later of the due date and the payment date. For this accounting period, credit interest could not have started before 14 October 2025, which is 6 months and 13 days after the period began on 1 April 2025.

Why is a Corporation Tax repayment delayed or held?

GOV.UK and HMRC's manuals describe four things that slow, hold back or reduce a Corporation Tax repayment: HMRC checking the return, other tax the company owes, a return without usable bank details, and a duplicate claim. HMRC first uses any refund to pay other tax the company owes (GOV.UK: Get a refund or interest on your Corporation Tax).

HMRC can hold back a repayment while it checks the return. HMRC's manual says that where it has valid grounds for believing the tax payable is in question, it believes it has the right to withhold the part of the excess that may not be due. It adds that if a repayment is held before an enquiry is formally opened, for example where HMRC suspects avoidance, the enquiry should be opened without undue delay (CTM92030). During an enquiry, an amendment the company makes to its own return does not take effect until the enquiry is completed, but a company that doesn't pay by instalments can still apply for a repayment before its liability is settled, and HMRC's staff are told to make it if the claim meets the legislation (COM71030). Keeping the working papers behind each figure on the return makes it quicker to answer any question HMRC asks.

HMRC can use money it owes the company to clear other debts first. GOV.UK says HMRC will use a repayment to pay other tax the company owes, for example PAYE or VAT, and will refund what is left to the original payment card, by Bacs to the bank or building society account, or as a payable order sent to the registered company address (GOV.UK: Get a refund or interest on your Corporation Tax). Section 130 of the Finance Act 2008 gives HMRC the power to set a credit it owes against a debit owed to it (FA 2008 s130). When part of a repayment is used this way, GOV.UK says the repayment confirmation appears in the business tax account. A director expecting the full overpayment back should check for overdue PAYE, VAT or other HMRC balances before chasing the Corporation Tax refund.

Missing bank details and duplicate claims are the avoidable delays. An overpayment of £100 or less is paid out only when the return gives bank details in boxes 920 to 940, and HMRC uses only the details on the latest return, so details given only on an earlier return won't be used (HMRC's CT600 guide). HMRC's Corporation Tax contact page asks companies waiting for a repayment from a claim not to send an amended return when a loss carry-back claim has already been made on the loss-making period, and not to send a duplicate claim in writing, because resubmitting may increase the time HMRC takes to review and process the claim (GOV.UK: Corporation Tax: general enquiries). The box 40 guide shows where the repayment tick sits on the return.

Can Taxley claim a Corporation Tax repayment on your CT600?

Yes, for an ordinary overpayment on a return Taxley can file. Taxley (taxley.co.uk), UK online software that prepares and files the Company Tax Return (CT600) with HMRC and the annual accounts with Companies House, lets you tick box 40 and send the company's bank details in boxes 920 to 940.

In Taxley's Advanced editor, the box 40 tick sits under "Anything unusual about this return?", and the bank details go in a separate "Repayment bank details" section marked as optional and only for a refund. Taxley sends the bank details only when all four required fields are complete: the name on the account, a 6-digit sort code, an 8-digit account number and the bank name, with a building society roll number added if the account has one. A nominee who should receive the money instead of the company can be added with a name, two address lines and a reference. Taxley's hint says to leave the section blank for a normal return, but HMRC's CT600 guide asks for bank details on every return (HMRC's CT600 guide), so filling them in each year does no harm and makes any small repayment payable.

Taxley's return flags the repayment but doesn't state the amount. Taxley doesn't fill in box 595 (tax already paid), box 605 (tax overpaid), box 860 (a repayment limit) or boxes 865 to 895, although HMRC's CT600 guide asks for boxes 865 to 895 when box 40 is ticked. HMRC's own account for each period sets the payments it has received against the tax charged and shows any overpayment (COM61070). Taxley works out section 455 tax on an outstanding director's loan and the relief due when the loan is repaid. It works out a 12-month trading loss carry-back and ticks box 45, but it doesn't file terminal loss claims, research and development or creative industry reliefs, or returns for companies paying by quarterly instalments, and it doesn't pay the company's tax or give tax advice. Do I need an accountant? lists what else it can't file, and a terminal loss claim needs an accountant or other software. Take the 30-second check to see whether Taxley fits your company.

Frequently asked questions

Can HMRC pay a Corporation Tax refund to someone other than the company?

Yes, if the return nominates them. HMRC's CT600 guide says the nominee's details go in boxes 955 to 965, the nomination is authorised in boxes 945, 950 and 970 on every return, and the nominee's bank details must be given. Payable research and development credits normally go only to the company.

Can a company get Corporation Tax back before it files the return?

Sometimes. HMRC's manual says tax paid before the normal due date can be repaid up to that date without pre-conditions. After the due date, a company can apply before its liability is final if its circumstances have changed and it states why it has paid too much.

Where does HMRC send a refund if the company paid by card?

Usually back to the card. HMRC's CT600 guide says that if the tax was paid by debit or credit card, repayments will normally be made to that card. Otherwise HMRC pays by Bacs to the account on the latest return, or by payable order to the registered office.

How can a director see whether HMRC has repaid the company?

Check the company's HMRC online account. HMRC's manual says its account screen shows the balance owed or the amount overpaid for each accounting period. Repayments appear only once HMRC has authorised them, so one still awaiting authorisation or held back won't show yet.

Is Corporation Tax repayment interest taxable?

Yes. GOV.UK says the interest HMRC pays on overpaid Corporation Tax is taxable and should be included as income in the Company Tax Return. That covers both repayment interest on overpaid tax and credit interest on tax the company paid early.

How long does a company have to reclaim section 455 tax?

GOV.UK says a company must claim within 4 years, or 6 years if the loan was repaid on or before 31 March 2010. The claim can't be paid until 9 months and 1 day after the end of the accounting period in which the loan was repaid, written off or released.