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HMRC internal manual

Construction Industry Scheme Reform Manual

Deductions: credit and repayment: contractor - making corrections after deduction

CISR72600 Action guide contents


The principle of the monthly return (CIS300) is that it should reflect what the contractor has actually paid and deducted in the tax month it covers, (a tax month runs from the 6th of one month to the 5th of the next).

Making corrections after submission of the CIS300

Once the contractor has completed and submitted the CIS300 to HMRC, any errors subsequently identified on that return will need to be corrected. This can be facilitated in a number of ways. The contractor can

  • Telephone the CIS Helpline on 0300 200 3210 (the preferred method)
  • Send in a new (corrected) return
  • Write in giving the correct details

All requests made by telephone to a local processing office to correct a return should be referred to the CIS Helpline on 0300 200 3210 as only calls to HMRC contact centres are recorded. This will ensure that a transcript of the call can be obtained in any case of dispute. See CISR66000 onwards for further details regarding Errors on Returns).

Making corrections before submission of the CIS300

There will be occasions when deductions at an incorrect rate are made from the subcontractor within a tax month, and the correction can be remedied by the contractor before the submission of the CIS300 to HMRC. In the majority of such cases it is likely that the contractor will make the correction without reference to HMRC and we will not know that a ‘correction’ has in fact been made.

If the contractor makes contact with HMRC to seek confirmation that they can indeed make the correction, in the first instance you should seek to establish full details surrounding the proposed correction before passing judgement on the matter, as each case will need to be considered on its own merits. However if the issue involves the contractor refunding to the subcontractor any excessive deductions based on a change of tax treatment in that month (as notified by HMRC) you should inform the contractor not to do so as the return must reflect what has actually been paid and deducted in the month.