NS&I has clarified what happens if a person wants to add to their guaranteed growth bonds account after setting one up.

The Government-backed provider is currently offering its Guaranteed Growth Bonds and Guaranteed Income Bonds at 6.2 percent with a one-year fixed rate.

Twitter user David Chapman (@CarefulChapman) contacted the group to ask if customers can buy an amount of bonds today and then invest in more later, or if they had to purchase them all at once.

NS&I said in response: “Once you’ve bought a fixed-term bond, you can’t add any more money to it.

“You can buy more bonds though if they are still on sale, up to a total value of £1million per person in the current issue. Each bond you buy is a separate investment with its own maturity date.”

The man then asked if an account could be opened with £2,300 or if a saver had to invest multiples of £500. The minimum investment for the accounts is £500.

They also asked: “If still on sale next week, the person puts more money towards another fixed term bond then the term would be one week after the £2,300 investment?”

The provider explained that a customer would be able to do this, adding: “So long as the minimum deposit of £500 is made, you can invest what you wish.

“If a further investment is made next week, however, this would open under its own account number and the one-year term would start from then.”

Financial journalist Martin Lewis pointed to the growth bonds accounts as being “jaw droppingly outstanding” last week.

He said a key benefit of the accounts is a person can hold up to £1million and all the savings are guaranteed by the Government.

Customers with Growth Bonds are paid their interest at the end of the term, while those with Income Bonds get their interest paid each month.

Mr Lewis said on his BBC podcast last week: “If you’re in that fortunate position to be sitting on a large amount of cash, to be able to put all of it in the top rate in perfect safety, is relatively unheard of.

“I don’t think those NS&I accounts are going to be around for very long, so 6.2 percent in total safety with a big name really is quite an eye wateringly different deal that’s available right now.”

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