ISA Addewid

Whatever you’re promising to save for – our Promise ISA gives you a competitive variable core rate plus a fixed bonus provided you make no more than two withdrawals each tax year.

Heb fonws amodol

  Balans Di-dreth^ y fl. AER†
Llog blynyddol £500 - £20,000 0.40% 0.40%
Llog misol £500 - £20,000 0.40% 0.40%

Gyda bonws amodol

  Balans Di-dreth^ y fl. AER†
Llog blynyddol £500 - £20,000 0.90% 0.90%
Llog misol £500 - £20,000 0.90% 0.90%
  • Open in branch
  • Save from £500 to £20,000
  • Interest is calculated daily and paid annually or monthly
  • Enjoy a bonus every year if you don't make more than 2 withdrawals per tax year
  • Enjoy the benefits of a flexible ISA
  • Withdraw your money at 30 days' notice or immediately with a loss of 30 days' interest
  • Closure permitted (and counted as a withdrawal)
Summary Box
  Summary Box
Account Name Promise ISA Issue 10
What is the interest rate?
Tax-free^ p.a.
Variable interest rate without bonus
Variable interest rate with bonus

Interest is calculated on your daily balance and paid annually on 6 April every year or monthly on the 6th day of each calendar month, depending on what you choose. The bonus is paid annually on 6 April. If the interest payment day is not a business day, interest will be paid on the next business day.
Can Principality change the interest rate? Yes, variable account rates could increase or decrease.

Customers will be given personal notification of any material reduction in interest rates a minimum of 14 days before the change takes effect.

To understand why rates may be reduced please refer to pages 13 and 14 of the Savings Terms and Conditions.
What would the estimated balance be after 12 months based on a £1,000 deposit? Based on the assumption that no further deposits or withdrawals are made during the 12 months.
Without bonus
With bonus
How do I open and manage my account?
  • You must be aged 16 or over, a UK resident for tax purposes and an individual applicant to open and operate this account.
  • Open your account in branch or agency.
  • The minimum balance is £500 and you can save up to the current annual Cash ISA limit of £20,000 (plus transfers-in of existing ISA balances) in this tax year. You need to keep the minimum balance in your account for it to remain open.
  • Manage your account in branch, agency, post or online via secure message (subject to Your Account eligibility criteria, available when you click “Register Now” at
Can I withdraw money?
  • Yes, all withdrawals from your account are subject to 30 days’ prior notice or loss of 30 days’ interest on the amount you withdraw, if you do not give 30 days' prior notice.
  • Closure permitted and this counts as a withdrawal.
  • The account offers a fixed bonus of 0.50% Tax-free^ as long as you don't make more than two withdrawals per tax year.
  • This is a flexible ISA Account. This means you'll be able to take money out of it and replace that money before the end of the same tax year, without the replacement contributing any further towards your annual ISA allowance. If you choose to have your interest paid into another account, this counts as taking money out under the flexible ISA rules, so you could pay in money to replace the interest removed, without it counting towards your Annual ISA Allowance.
Additional information
  • Service charges and costs may apply to your account. These are outlined in our Tariff of Charges.
  • In certain circumstances we may refuse an instruction to operate an account. These circumstances are outlined on page 5 of the Savings Terms and Conditions.
  • Rates correct as at 16/05/17.
Calculate your savings

Savings calculator

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Amount must be less than 20000

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Amount must be less than 20000

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  1. The results displayed were dependent on the information you provided and are for illustrative purposes only and are by no means an indication of being suitable for your individual circumstances.
  2. The calculations assume interest is paid gross* of income tax on the entire balance on an annual basis
  3. It has been assumed that no withdrawals or additional deposits would be made from the account during the saving duration, and that the interest rate also remains the same during this time (note that interest rates on variable rate savings account are subject to change, and when fixed rate deals end, there is no guarantee that the same rate will be available in the future). 

Before you apply below, please read the Telerau ac Amodau ISA Addewid Rhif 10

Os ydych yn trosglwyddo cyfraniadau ISA blynyddoedd blaenorol yn unig, nodwch mai £500 yw eich adnau dechreuol ar eich ffurflen gais. Bydd y ffurflen gais yn gofyn i chi a ydych yn trosglwyddo yn ddiweddarach yn y broses.

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

Gan y byddwch yn rhwym i Delerau y Cyfrif ISA, mae'n rhaid i chi eu darllen. Os nad ydych yn deall unrhyw un o'r telerau ac amodau cysylltwch â ni i gael mwy o wybodaeth.

Rydym yn argymell eich bod yn argraffu ac yn cadw copi o'r telerau ac amodau hyn ar gyfer eich cofnodion.

Darllenwch y canlynol hefyd:

^ Mae di-dreth yn golygu nad oes yn rhaid talu Treth Incwm a Threth Enillion Cyfalaf y DU ar y llog a enillwch. Mae eich sefyllfa o ran treth yn dibynnu ar amgylchiadau unigol a gall newid yn y dyfodol. 

† Ystyr AER yw Annual Equivalent Rate (Cyfradd Gyfwerth Flynyddol) ac mae’n dangos faint fyddai’r gyfradd llog pe byddai’r llog yn cael ei dalu a’i adlogi unwaith y flwyddyn.


ISA Addewid Rhif 10

  • 6ed cymdeithas adeiladu fwyaf y DU
  • Cymdeithas adeiladu gydfuddiannol, sy’n eiddo i’n 500,000 o aelodau ac yn cael ei rhedeg er eu lles
  • Dros 150 mlynedd o brofiad
  • Gofalu am werth dros £8 biliwn o asedau ein cwsmeriaid
  • Members can access a Member Rewards page featuring competitions, discounts and more.