Local MP Alan Mak has urged Lloyds and the Halifax not to close branches in Havant.
He has written to the Lloyds Banking Group, which also owns the Halifax, asking it to reconsider the decision to pull out of the town.
The Halifax is scheduled to close on January 15, 2026, while Lloyds is due to shut four days later.
If they do go, only the Nationwide branch and Barclays operating at Havant Library will be left in the centre of Havant.
Although Barclays closed its East Street branch in 2022, Mr Mak managed to get the company to maintain a presence in Havant Library at the Meridian Centre.
The big banks are closing branches across the country because of the growth of online and phone banking.
Mr Mak said: "It is disappointing that Lloyds and the Halifax in Havant are due to close and I've written to the Lloyds Banking Group urging it to think again.
"While it is true that many people do bank online today, others do still want and need an in-person service."
He added: "Nationwide and Barclays still have a presence in Havant, so I would urge people to keep using them to show there is local support for banks to stay open in Havant."
