This subject is not specifically covered in the Charities Act 2011 but all prospective trustees are required to sign a Declaration of Eligibilty, essentially confirming the individual is not disqualified from acting as a trustee. That Declaration would cover the period prior to gender reassignment. The potential trustee in question would not, therefore, be required to disclose the name they were known by when of a different sex. A link to the Commission's model Declaration Form can be found at https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/490837/trustee_declaration_v_8.pdf Please note that this particular Declaration Form is intended to be used by trustees who are applying to register a charity with the Commission and so is not suitable for internal use by charities but it can be used as a template for the charity to design its own Declaration for potential trustees to sign and such forms would be retained by the charity for its own internal records. If the Declaration is later found to be false, the person would then automatically cease to be a trustee and may be subject to a criminal sanction for knowingly providing the charity with false information. In some cases it may be necessary to disclose any previous names and that will largely depend on the nature of the charity and its beneficiaries. If the charity trustees will work closely with children or vulnerable adults they will need to undertake background checks by the Disclosure and Barring Service. For detailed information on trustee eligibility go to the Commission's website and type CC3 into the search box at the top of the homepage which will then take you to "The Essential Trustee: what you need to know".