Halifax has alerted customers about a key letter going out to savers about a change to their accounts. A confused customer reached out to the bank after receiving a notification in the banking app about a letter they had been sent.

The letter made referred to their bonus saver scheme "ending soon", and also had some information about an instant saver account. To clear up the confusion, Halifax said in response: "After 12 months the account changes to an instant saver."

The Bonus Saver offers a 3.05 percent interest rate across a 12-month term. This rate applies provided you make no more than three withdrawals during the 12-month span. Making four or more withdrawals results in the interest rate plummeting to 0.95%.

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The interest for this account is paid monthly, on the same day the account was opened. To open the account, you only have to deposit £1 and you can put in up to £9 million.

Nevertheless, once you reach the end of the 12 months, the account becomes an instant saver, offering a significantly lower interest rate of just 1.35%, meaning a reduction in your interest rate of 1.7%.

Moreover, those with a Bonus Saver should be aware that the interest rate is variable, so Halifax can change it at any point. The Halifax website provides this guidance: "We'll always let you know of any planned changes to the rate.

"Our account conditions explain when and how we do this. For example, we might change it if it costs us more to run this account for you." The account can be managed online, through the app, in branch or over the phone.

If you open the account and decide later on you don't want it, you can cancel the account free of charge within 30 days of opening. Halifax customers with an easy access savings account have the option to renew it into a bonus saver without needing to open a new account.

In other savings news, customers with Nationwide Building Society may want to note they have just days left to take advantage of a £200 switch offer. Existing members can get the bonus cash when switching from non-Nationwide account to a new or existing FlexPlus, FlexDirect or FlexAccount account.

The offer is available until Thursday, July 10. You can check if you qualify using the checker tool on the Nationwide website.