Of course it is, we hope, and this is at the core of the Fundraising Promise, which every organisation agrees to when they register with the Fundraising Regulator https://www.fundraisingregulator.org.uk/about-fundraising/resources/fundraising-promise.
However, we note that the Charity Commission has recently opened a number of statutory inquiries where they feel there are questions to be answered. You can read more at https://www.gov.uk/government/organisations/charity-commission.