All the offices will operate from 9 am to 3 pm in the next three days, from 28 to 30 July, the government has announced.
In the last week, the offices were open for only four hours on the last two working days, Wednesday and Thursday.
The decision on extending the office hours came as the authorities are trying to restore normalcy after days of clashes and curfew over the quota reform movement.
The situation is improving across the country, and the government is relaxing the curfew gradually.
Earlier, the government announced a general holiday from Sunday to Tuesday, in addition to imposition of curfew, to tackle the unrest.
An official from the public administration ministry said while office hours have been extended, other conditions of the recent general holiday will remain unchanged.
Essential services, including power, water, gas, fuel, fire service, port operations, sanitation, telephone, internet, postal services, and associated workers, will continue to operate without restriction, he added.
At the same time, healthcare facilities and emergency services will remain outside the purview of the restrictions.