Martin Lewis is urging people to claim £170 for free before the offer runs out in just five days time.
The cash is offered as an incentive for bank customers to switch to HSBC's Advance current account from another banking provider. Anyone wanting to claim the cash must do so by July 18.
And it's not available to everyone. In order to be eligible for the switch reward, you can't have had an HSBC current account, or opened one with its sister bank First Direct, since January 2019, to claim the cash.
READ MORE: Martin Lewis 'feels sick' as he urges people to prepare for energy price cap predictions
Customers must also transfer over at least two direct debits or standing orders and pay in at least £1,500 in the first 60 days. The £170 is then paid within 30 days.
According to Mr Lewis' article on Money Saving Expert, you must also be moving from a current account that's not with HSBC or First Direct. There is no minimum pay-in.
Similarly, First Direct's 1st Account is offering those who make the switch £150 for free. Many customers also get a £250 0% overdraft.
The account is also linked to a regular saver which pays 3.5% interest on up to £300 a month. To get the bonus, similarly to above, you can't have had a First Direct account before - or opened a current account with HSBC since January 2019 - and you must be switching from a current account that's not with First Direct or HSBC.
Once you've opened the account, you need to make the switch from another current account within three months and pay in at least £1,000. The £150 is then paid within 28 days. There is no set date listed for this offer to end, though First Direct's website states: "Offer can be withdrawn at any time."
Receive newsletters with the latest news, sport and what's on updates from the Liverpool ECHO by signing up here
READ NEXT:
Iceland boss issues warning over worrying new trend as food prices rise
Mum and dad fined after 'top of the year' pupil misses school
Full list of days when Ryanair and easyJet staff plan to strike in Spain
Coleen Rooney's verdict on moving to America ahead of Wayne's new career move
ITV Loose Women Coleen Nolan's reaction to son's wedding leaves Shane Richie baffled