The fund waives arrangement fees on lending and is designed to help with any cashflow shortages caused by the floods.
It was originally put in place as part of a range of support measures for those affected by Storm Desmond but it is also accessible to those impacted by further flooding.
Bank of Scotland area director for SME banking, Graham Blair, said: “We know how critical it will be for businesses affected by the floods to receive support with their cashflow and help them through any interruptions to their business.
“The aim of this fund is to help businesses with their working capital needs and cashflow shortfalls – for example, by allowing farmers to find food and shelter for livestock or small businesses to pay employees whilst they get their businesses up and running again.”
This announcement is in addition to a range of support already being provided UK wide by Lloyds Banking Group, for businesses and individuals across the affected regions.
Businesses can apply through Bank of Scotland branches and business centres.