Maturity 1 Year Fixed Rate Cash ISA (FRISA136)

This is a maturity product, it’s designed to reward you as one of our loyal savings Members, you will benefit from higher rates than the products on sale to new customers. Our Maturity 1 Year Fixed Rate Cash ISA may be right for you if you have a lump sum to invest and you can leave your investment untouched for 1 year.

  Interest Rate Balance Tax-free^ each year AER†
Maturity Interest £500 - £20,000 4.55% 4.55%
Monthly Interest £500 - £20,000 4.46% 4.55%
  • You can only open this account if you have a Principality fixed term account coming to the end of its fixed term
  • Open this ISA in branch, at an agency, by post or online
  • Pay in from £500 to £20,000 in the current tax year
  • Transfer in your existing ISAs
  • You can add more money for up to 5 business days from the date you open it
  • Choose to have interest paid at maturity or every month
  • No withdrawals allowed before the end of the one-year term
  • If you close, or transfer the ISA early you must give up 90 days' interest
  • We can stop accepting applications at any time. While it remains available you can only open it within 14 days of the date your existing Principality fixed term account comes to an end
Summary Box
  Summary Box
What is the interest rate? Fixed annual interest      4.55% Tax-free^ each year     4.55% AER†
Fixed monthly interest    4.46% Tax-free^ each year     4.55% AER†

(See the meanings of 'Tax-free' and 'AER' at the bottom of this page)

Interest is calculated each day on the money in the account and paid:
  • at maturity, on the anniversary of your account opening or;
  • monthly, starting one month after the date your ISA is opened, and then each month after that;

  • whichever you choose.
    Can Principality change the interest rate? No, the rate is fixed for one year until the ISA matures (when the account comes to an end).
    What would the estimated balance be after 12 months based on a £1,000 deposit? £1,045.50

    This is based on you choosing to have interest paid at maturity and added to your ISA and you not making any further payments into the account.
    How do I open and manage my account?
    • You must be a Principality customer with a fixed term savings account coming to the end of its fixed term (maturing).
    • You must be 16 or over and a UK resident (see your Maturity 1 Year Fixed Rate Cash ISA account terms).
    • You can move money from your maturing Principality account in branch, at an agency, by post or online.
    • You must keep at least £500 (the minimum balance) in the account.
    • You cannot pay in more than the ISA Allowance each tax year. The ISA Allowance for the current tax year (2023/2024) is £20,000.
    • You can transfer unlimited amounts from ISAs from previous tax years, as these are not part of your current year’s ISA allowance.
    • You can keep making payments into your ISA up to 5 business days after opening the account.
    • Your ISA will mature after one year, on the anniversary of the account opening.
    • You can manage the account in branch, at an agency, by post, or by using the online service Your Account at
    • You can open the account up to 14 days after the date your existing Principality account matures unless we remove it from sale. We can stop accepting new applications for this account at any time.
    Can I withdraw money?
    • No, you cannot make withdrawals from your ISA before it matures.
    • If you close, or transfer your ISA before the end of the fixed-rate term (within one year), you will lose 90 days of interest. If you haven’t earned enough to cover the 90 days’ interest it will be taken from the money in the account. This means you may get back less than you originally put in.
    • We will write to you before your ISA matures to find out what you want to do with your money.
    • If we don’t receive any instructions from you before your ISA matures, we will move your money to our Variable Rate Cash ISA or the nearest equivalent we offer at the time.
    Additional Information
    • Service charges and costs may apply to your ISA. These are set out in our Tariff of Charges.
    • In certain circumstances we may refuse an instruction for using an account. These circumstances are set out in our Savings Terms and Conditions.
    • The tax treatment of your savings depends on your individual circumstances and may change in the future. This is set by HM Revenue and Customs (HMRC).
    • The interest rates quoted above were correct on 15/02/2024.

    Before you apply, please read the Maturity 1 Year Fixed Rate Cash ISA (FRISA136) Terms & Conditions

    You can only invest in one Cash ISA per tax year.

    As you will be bound by the account terms and your information is held in accordance with our privacy policy, you should read, print and save the below documents for your records. If you have any queries relating to them please contact us for further information.

    Please also read the following:

    ^Tax-free means UK Income Tax and Capital Gains Tax is not deducted from the interest you earn. This depends on your individual circumstances, and may change in future.

    †AER stands for Annual Equivalent Rate and illustrates what the interest rate would be if interest were paid once each year on the whole balance, including previous interest payments. 

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