From 1 October 2014, if you file an SDLT return on paper you must enter a valid local authority code at:

  • question 29 of form SDLT 1, and if applicable
  • question 2 of form SDLT3 and question 10 of form SDLT 4.

You can find a list of valid local authority codes in HMRC’s online SDLT Manual at SDLTM62320.

Returns which do not include a valid code will be rejected and returned to you. This will lead to delays in receiving the SDLT certificate and may ultimately result in late filing penalties.

If you file returns electronically (approximately 96 per cent of returns are filed electronically) you will still need to complete the local authority code but you will not be able to submit the return if the code is invalid - the return will not be validated if the code is omitted or is incorrect.

Please note that if you submit returns electronically, you will receive an SDLT 5 almost instantaneously.