HSBC has said it will close its branches in Llanfyllin and Llanfair Caereinion, just weeks after the banking giant announced it will also close in Whitchurch and Market Drayton.
It said it has made the decision to close the two Mid Wales branches because they have become financially unviable with more and more people using internet banking. Staff will be transferred to other branches.
Montgomeryshire MP Glyn Davies, Assembly Member Russell George and Llanfyllin county councillor Peter Lewis said they are all "deeply disappointed" by the announcement.
Mr Davies said: "The closure of the HSBC banks in Llanfyllin and Llanfair Caereinion is a huge blow to both towns, along with those who care about our rural services. I am meeting with HSBC's regional director Rachel Thomas to find out what hope there is of a change of heart.
"It's vital that HSBC make it a top priority to discuss new arrangements with elderly customers, and to lessen the impact of this decision as far as possible if the bank decides to force these proposals through."
Mr George who is also meeting with Ms Thomas, said he hopes HSBC will think again, before implementing what he called "devastating changes".
Councillor Lewis said he will work with fellow councillors in Llanfair Caereinion to limit the impact. He said: "I've written to HSBC's regional manager, insisting she comes to Llanfyllin to explain in person the reasons for these decisions.
"The loyal staff must be protected, and arrangements must be put in place to help the elderly and those with special difficulties. It's another desperate blow to local services."
The two banks will close on February 12 with HSBC saying it will improve internet facilities to help its customers.