If you’re paying Inheritance Tax on an estate, you must get an Inheritance Tax reference number and payslip before you pay. The reference number will be unique to the estate and you should use it on all payments of Inheritance Tax and correspondence with HM Revenue & Customs (HMRC).
When there’s no Inheritance Tax to pay on an estate you should not apply for a reference number.
This includes cases where there is no Inheritance Tax to pay because you are transferring a late spouse or civil partner’s unused threshold (or ‘nil rate band’) to the second partner when they die.
In these cases, HMRC will allocate you a reference number when it receives your forms and paperwork as part of the probate process (or confirmation in Scotland).
1. Gather the following information about the deceased before filling in the form, as you can’t save the form and go back to it later:
2. Access the online form using the link below.
3. Ensure all information about you and the deceased matches the information you put on form IHT400 Inheritance Tax Account.
4. When HMRC receives your reference request, it will send the reference number to you - by post - along with a pre-referenced payslip (unique to the estate).
5. Put the reference number on form IHT400 before you send it to HMRC, and use the payslip to pay any tax due on the estate.
Apply for an Inheritance Tax reference number online
You won’t be able to use the online form if the deceased didn’t have a National Insurance number. This may be because they didn’t live in the UK or they were a minor.
In this case, download form IHT422 below, and send it to HMRC at the address below:
HM Revenue & Customs
Trusts & Estates Inheritance Tax
Ferrers House
PO Box 38
Castle Meadow Road
Nottingham
NG2 1BB
DX 701201 NOTTINGHAM 4
Get form IHT422 to apply for an Inheritance Tax reference (PDF 35K)
You can't use the online form for a trust. In this case download form IHT422 using the link below and send it to HMRC at the following address:
HM Revenue & Customs
Trusts & Estates Inheritance Tax
Ferrers House
PO Box 38
Castle Meadow Road
Nottingham NG2 1BB
DX 701201 NOTTINGHAM 4
Get form IHT422 to apply for an Inheritance Tax reference (PDF 35K
The form should work on most computer systems, but it is incompatible with some older browsers and individual computer settings.
If the online form doesn’t open properly, or you can’t fill in the boxes:
If this doesn’t work, please use form IHT422 to apply for a reference instead (see the link and section above).
Unfortunately, HMRC can’t provide technical support.
Contact the Probate and Inheritance Tax Helpline
Find out more about Inheritance Tax and the probate process
Read more about paying Inheritance Tax