The Bendigo Bank branch at Wanniassa will close on September 29.
The bank blames "a change to commercial leasing arrangements at the Wanniassa complex and fewer instances of in-branch transactions".
It is telling its Wanniassa customers they will have to do their over-the-counter transactions at the Curtin or Calwell branches.
The shock closure comes after the Bendigo Bank opened in Wanniassa in a blaze of publicity as it vowed to fill the void left by the closure of the Commonwealth Bank branch at the same location in 2001.
The closure of the Commonwealth Bank in Wanniassa 21 years ago prompted huge protests. The arrival of Bendigo Bank was hailed as a return to community, face-to-face banking.
The Bendigo and Adelaide Bank on Wednesday distanced itself from the decision to close the Wanniassa branch.
"The bank operates a community bank model which includes more than 300 branches across Australia. These branches are independently owned and operated," a statement from the bank read.
"The Wanniassa branch is one of three branches owned and operated by Molonglo Financial Services (MFS) Limited.
"The board of MFS, our community bank partner, have made the difficult decision to close its Wanniassa branch. Bendigo and Adelaide Bank Ltd has agreed to the decision.
"The decision to close the branch was not made lightly by MFS and followed a change to commercial leasing arrangements at the Wanniassa complex and fewer instances of in-branch transactions as customer preferences continue to evolve."
It's understood the neighbouring Capital Chemist is planning to move into the space left by the bank branch.
There has been speculation the bank might have some kind of presence in the expanded chemist, such as an ATM, but that has not been confirmed.
"The bank is still exploring options with [Molonglo Financial Services] to find a suitable location that is closer to Wanniassa than Calwell and Curtin," a spokesperson said.
"This decision has not been made by the bank, but at a local level by the board of MFS Limited," the spokesperson said.
"The branch closure does not change the commitment by the MFS board and branch staff to ongoing community investments in Wanniassa and surrounds via our grants, donations and sponsorships program. We look forward to continuing to support our customers and the wider community from our Calwell and Curtin locations."
The bank said no further branch closures were planned in Canberra and all staff from Wanniassa would be redeployed.
"There are two full-time and one part-time staff members at Wanniassa who have all accepted positions at our Curtin and Calwell branches. There are no redundancies," the spokesperson said.
"We are delighted that our Wanniassa staff have accepted offers to continue working within our ACT community bank network. Boosting staff numbers in our other branches means better customer service with more resources devoted to responding to customer enquiries and of course, our continuing community outreach work."
Bendigo Bank told Wanniassa customers all over-the-counter transactions could be conducted at Curtin (9km away) and Calwell (7.3 km away) community banks.
"Customers have the option of using the Coles supermarket next door to the Wanniassa branch as a cash-out option," the spokeperson said.
"The bank has also recently reached an agreement with Australia Post so that concession account holders can transact fee-free using Bank@Post at any LPO [local post office]. The bank is in the process of communicating these network changes to customers."
There is also no post office at the Wanniassa shops.