This department is responsible for administration of the city's financial affairs. This includes maintaining accounting records for all operations, custody and investment of funds, supervision of revenue collection and disbursements of city monies, administration of debt, payroll function, audit and budget preparation.

The Government Finance Officers Association (GFOA) recognized the City of Andover with the Distinguished Budget Presentation Award for the 2014 budget document. This award is the highest form of recognition in governmental budgeting, and its attainment represents a significant achievement by the City of Andover. In order to receive this award, a governmental unit must publish a budget document that meets program criteria as a policy document, as an operations guide, as a financial plan, and as a communications device.