The Carnforth branch of NatWest bank will close next year.
The bank will shut on June 6 2017 – one of 14 closing across the county, leaving residents with miles to travel to reach their nearest branch.
NatWest said an increase in mobile and online users and a decline in branch users was the reason behind the “difficult decision”.
A NatWest spokesman said it was contacting its “vulnerable and regular customers” and admitted many customers weren’t confident with online and mobile banking.
Digital experts are set to be stationed at closing branches to support users with digital banking.
Coun John Reynolds, a Lancaster city councillor for Carnforth, said it was a “short sighted” decision.
“Hundreds of new houses are due to be built in the Carnforth area over the next 10 years and people will need these services,” he said.
“We also have a large population of elderly people who won’t find it easy to get to Lancaster or Morecambe.”
A spokesman for NatWest said: “The way people choose to bank with us has changed radically over the last few years.
“Between 2010 and 2015, mobile and online transactions have increased by over 400% and mobile transactions alone have increased by 1,350%.
“As a result of this change, we have seen the number of transactions in Carnforth branch declining by 18% since 2011 and 50% of the customers of the branch are actively choosing to use online and or mobile banking for their day to day banking needs.
“We are communicating with our customers affected by the closure and proactively contacting vulnerable and regular branch customers.”
The nearest branch for NatWest customers will be in Morecambe, six miles away.