Bristol City Council has developed its online open source operating system with outsourcer Capgemini to help streamline and improve its web services.
Bristol's move towards council wide open source adoption to save money started in 2010, and won central government support at the end of last year.
The new website platform is based on Drupal open source software, which the council says will add "flexibility and freedom when adding new online services", including both interactive transactional facilities and expanded information content.
Gavin Beckett, chief enterprise architect at Bristol City Council, said: "Moving to Drupal, with its extensive ecosystem of openly available modules and service providers, gives us the flexibility to enhance and extend the website in future to match changing customer needs."
Beckett said the streamlined website reduced the number of pages from 10,000 to 3,000, making searching for information and completing transactions "much quicker, easier and more intuitive than previously".
The move to Drupal, he said, also supported an expanding local ecosystem of IT companies - at the moment seven of them - involved in developing additional online services on behalf of the council.
The website project is one of the first to be completed under Bristol City Council's long-term contract with Capgemini, which has an operations centre in the area.