Members of the community and the city’s leaders will mingle at the event which kicks off with a reception of canapés and wine.
One Voice Community Choir will lead the congregation with songs including O Little Town of Bethlehem, Away in a Manger, Joy to the World, Hark the Herald Angels Sing and Silent Night.
The event at Preston Town Hall in Lancaster Road will start with a welcome message from mayor coun Trevor Hart.
Reading with be given by Christine Abram, coun Peter Kelly and mayoress Laura King with a message from Rev Michael Everett.
Carols in the Chamber takes place on Thursday, December 6 at 7pm with reception starting at 6.30pm.
Proceeds go to Headway, the charity which raises funds and provide care for people with brain injuries, in both Preston and Chorley areas of Lancashire.