From my payments are deducted 20% CIS, there is no place in CT600 to reclaimed it. Now I got tax to pay but HMRC already took 20%. HMRC will calculate it and deducted it from tax to pay ? Thank you for help
Great question — CIS deductions can be confusing when it comes to Corporation Tax.
The short answer: HMRC will not automatically offset your CIS deductions against your Corporation Tax bill. You need to claim them via Box 515 (Income Tax Deducted from Profits) on your CT600 return, which tells HMRC to credit the tax you have already paid through CIS against your Corporation Tax liability.
The limitation with TinyTax: TinyTax does not currently support Box 515, so if you file your CT600 through TinyTax, your CIS deductions will not be included in the return and HMRC will not automatically offset them.
Your options:
1. Use specialist software (such as TaxCalc or Taxfiler) to file your CT600 with Box 515 included — this lets you claim the CIS credit directly in the return.
2. File through TinyTax then claim separately — file your CT600 as normal, then contact HMRC's Corporation Tax helpline or write to them with your CIS deduction statements to claim the credit. HMRC will apply it as a repayment or offset against other liabilities.
Make sure you keep all CIS deduction statements from your contractors — you will need them either way.
For more detail see our full guide: https://tinytax.co.uk/support/cis-deductions
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The short answer: HMRC will not automatically offset your CIS deductions against your Corporation Tax bill. You need to claim them via Box 515 (Income Tax Deducted from Profits) on your CT600 return, which tells HMRC to credit the tax you have already paid through CIS against your Corporation Tax liability.
The limitation with TinyTax: TinyTax does not currently support Box 515, so if you file your CT600 through TinyTax, your CIS deductions will not be included in the return and HMRC will not automatically offset them.
Your options:
1. Use specialist software (such as TaxCalc or Taxfiler) to file your CT600 with Box 515 included — this lets you claim the CIS credit directly in the return.
2. File through TinyTax then claim separately — file your CT600 as normal, then contact HMRC's Corporation Tax helpline or write to them with your CIS deduction statements to claim the credit. HMRC will apply it as a repayment or offset against other liabilities.
Make sure you keep all CIS deduction statements from your contractors — you will need them either way.
For more detail see our full guide: https://tinytax.co.uk/support/cis-deductions