The rebuild was triggered by an assessment of the buildings as earthquake prone and the layout of the buildings, particularly the crematorium, compromised staff safety.
The open day, will also give the public the chance to take a behind-the-scenes tour of the facility including the current crematorium area to the rear of the chapel and get an insight into the "science of grave digging", Mr Bowles said.
Mayor Lawrence Yule said there was a "strong public service component in the region being able to rely on having a crematorium and chapel that allows people to bury their loved ones with dignity".
The open day will run between 10am and 3.30pm at the cemetery and crematorium, in Orchard Rd, Hastings.