Lilias Day is a Kilbarchan festival said to be named after Lilias Cuninghame, daughter of an 18th century laird. In the past, Lilias Day was celebrated with a cattle market and races, with a procession through the village of men from different trades banging drums and waving flags. The Lilias Day tradition died out at the end of the 19th century, but has been restored in recent years.
Nowadays the village is decorated with flags and there is a fancy dress parade which includes a Festival Queen and her maids. The procession also includes figures from Kilbarchan history including a town crier, jester, St Barchan, druids and monks. Crowds gather to watch as St Barchan knocks on the door of Steeple Building and calls to Habbie Simpson to join the procession. Habbie comes down from the steeple, while his statue is covered by a flag. After a day of celebration, with entertainments of all kinds following the crowning of the festival Queen, Habbie returns to the steeple at midnight, bringing Lilias Day to an end for another year.