Castle Trust Bank savings rates — compare every account, plus switch offers and guides

Who they are

Castle Trust Bank began life as Castle Trust in October 2012, backed by J.C. Flowers & Co., a US private investment firm with deep experience in financial services. It started out focused on investment products and specialist mortgage finance, and has grown steadily since. In 2018 the business was invited to pursue a banking licence and, in June 2020, became Castle Trust Bank - a fully authorised UK bank. It is not a name you see on the high street, but in the financial year to September 2025 the bank made a profit before tax of £9.4 million, with around 36,000 customers holding just under £1.5 billion of savings. Alongside savings, it covers specialist bridging and term mortgages and retail finance - savings deposits effectively fund that lending book.

Savings accounts

The one product currently listed on DepositScout for Castle Trust Bank is the Notice e-Saver. It is a 120-day notice account paying 4.20% AER (variable) with a minimum balance of £1,000. Notice accounts were added to the savings range in May 2024, and there are no introductory bonuses or teaser rates attached - the rate you see is the rate you get, at least until the bank decides to change it.

The 120-day notice period is the central thing to weigh up. You need to submit a withdrawal request and then wait four months before the money arrives - a meaningful restriction that suits savers who know they will not need quick access to the funds.

On FSCS protection, eligible deposits with Castle Trust Bank are protected up to a total of £120,000 by the Financial Services Compensation Scheme. That limit is higher than the standard £85,000 you see at most banks, so it is worth noting if you are depositing a larger sum.

Is it right for you?

Castle Trust Bank suits a specific kind of saver - someone who has money set aside that genuinely will not be needed for at least four months and who wants a clean, no-bonus rate rather than a teaser that drops away. The online and app experience draws positive feedback, with customers noting the process from application to funding going through smoothly and quickly. There are currently no switch bonuses or current account products here, so if a switching incentive is part of what you are looking for, you will need to look elsewhere.

As always, the rate on this account is variable and can change. Check the live figure shown on this page before you apply - that is the most up-to-date number we have.