This part of GOV.UK is being rebuilt – find out what beta means

HMRC internal manual

Trusts, Settlements and Estates Manual

Trust income and gains: enquiry into income from a trust - how to check settlor's deemed income

If you have doubts about the validity of the form R185 (Settlor) or the amounts shown, you can ask the relevant Trusts & Estates Office (TSEM1415) if they can verify the amount of income arising to the trustees that is treated as the settlor’s. Form R185 (Settlor) shows the trustees’ name and the tax reference of the trust.

Suggested memo:

‘I have an open enquiry into my taxpayer’s [return/repayment claim] for the income tax year [year]. My taxpayer [name] states s/he is taxable on income arising to your trust on which tax was paid in the following amounts:

amount of income £

tax paid by trustees

Can you please confirm this from your trust return for [year]?’