Nationwide Building Society has explained how the interest rates work for its accounts after a saver was surprised to see they had a rate of 0%.

The customer contacted the group over X saying: "I've just opened the Flex Regular Saver last night and currently in the app that account is telling me it's 0% interest rate."

They asked if this would be updated once they put some money into the account or if it would go up after 24 hours of the account being open.

The Flex Regular Saver offers an attractive 6.5% rate at the time of writing. You can deposit up to £200 a month into the account.

You can make up to three withdrawals during the 12-month term for the account and keep the rate, although upon making your fourth withdrawal, the rate will drop to 1.75%.

Nationwide said in response to the customer: "The interest rate will show as 0% until you deposit funds into the account, after which it'll update to the advertised interest rate. Hope this helps."

You can manage the Flex Regular Saver online using the Internet Bank service or via the banking app. You need to have a Nationwide current account to set up the savings account.

One perk of joining Nationwide from another savings provider at the moment is that you can get £175 in free cash as a switching incentive.

The offer is available if you switch from a non-Nationwide provider to a FlexPlus, FlexDirect or FlexAccount. If you already have one of these accounts, you can still bag the cash if you bring over some funds from another provider, as long as you meet the other criteria.

A customer recently asked Nationwide about the rules for the offer. The puzzled person asked: "I'm a little confused. As for depositing £1,000 into the switched over account, within 31 days of requesting the switch to qualify for £175 cash, does this mean from date of application, or from the earliest switchover date available?"

on the Nationwide website explains that to secure the £175, you need to deposit at least £1,000 into the new account "within 31 days of requesting the switch".

Clarifying the situation, the building society said in response to the customer: "You would need to add the £1,000 within 31 days of requesting the application rather than when the switch took place."

Also within this 31-day period you have to pay for something once using your new debit card for the account. Another person asked this question about the cash incentive, saying: "How long on average does the process take from applying to switch from another bank to your guys current account to receiving the £175 incentive?

"I'm currently just awaiting the card and pin in post to make my first purchase via card to get the £175." The building society responded to say the overall timeframe can vary.

The group added: "When you complete the criteria, you'll receive a text confirming this and then payment is made within 10 working days of the text."