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Timeline to submit CT600 with HMRC

Timeline for filing CT600 alongwith iXBRL accounts and penalty for delay

By when should you file company tax returns?

There is no universal deadline to file a company tax return. The date is unique to each company depending on the accounting period.

There are two aspects to be dealt with:

  • corporation tax , for which the deadline is nine months and one day after the end of your accounting period for your previous financial year , for those businesses with taxable profits under £1.5 million. (In case your taxable profits be over £1.5 million then you will need to pay your corporation tax in four instalments and the process is different.)
  • company tax returns has to be filed with HMRC, for which the deadline is 12 months after the end of the accounting period it covers.

Corporation tax is usually charged for accounting periods for one year, except for the periods when a company starts and ceases, or if there is a change of accounting date. If the accounting periods in excess of 12 months, then more than one tax return will be required as a tax return cannot extend over a period of more than 12 months.

Company tax return for first year of trading

If you've just started your business, you may have two Corporation Tax accounting periods. As a Corporation Tax accounting period can’t be longer than 12 months, it is possible that in the first year of business your company may have to two sets of Company Tax Returns (even though you only need to file one set of accounts at Companies House.)

  • The first accounting period covers the first 12 months, i.e. starting from the date your company was incorporated to the end of 12 month period.
  • The second accounting period covers the rest of the time, i.e. starting from the end of the 12 month period above, running to the end of the month.

For example, if your company was incorporated on 10th December 2019, your company tax returns needs to be filed for two accounting periods:

  • The first company tax return for the accounting period 10th December 2019 to 9th December 2020 (12 month period)
  • The second company tax return for the accounting period for the balance of the month i.e. from 10th December 2020 to 31st December 2020

From second financial year onwards only one company tax return will need to be filed. You will receive a ‘notice to deliver’ from HMRC informing you when these payments are due.

What is the penalty for late filing of company tax returns?

The table below sets out the penalty applicable for late filing of corporation tax:

Late By Applicable Penalty
One day £100
three months additional £100
six months HMRC will calculate the corporation tax due and will add a penalty of 10 percent of the unpaid corporation tax
twelve months additional 10% of the unpaid corporation tax

Read Next :

HMRC company tax returns filing | How to prepare iXBRL accounts?

How To Prepare iXBRL and File CT600

Simple 4-step process to convert your annual financial statements to iXBRL and file company tax returns with HMRC.

1. Sign In

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2. Pay and Upload

necessary documents in Excel, Word or PDF format

3. Download

iXBRL package when ready within required turnaround time

4. Submit

CT600 with iXBRL to HMRC. We assist you in filing.

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