The service at the Carterton Events Centre from 2pm would be attended by family members of some of the victims as well as local emergency services workers.
Guests will include Governor-General Lieutenant General Sir Jerry Mateparae and his wife Lady Janine, Police Commissioner Peter Marshall and many of the mayors from the Wellington region.
Mr Mark said the whole of the Wairarapa and people from the wider Wellington region backed the community after the tragedy.
"This included those who dropped in flowers and home baking, the members of the emergency services and victim support who assisted those affected by the accident, the people who visited Carterton over the days after the crash, and all those who sent messages of support."
Those killed were pilot Lance Hopping, 53, of Masterton; husband and wife Howard, 71, and Diana Cox, 63, of Wellington; husband and wife Desmond, 70, and Ann Dean, 65, of Masterton; cousins Valerie Bennett, 70, of Masterton and Denise Dellabarca, 58, of Paraparaumu; partners Stephen Hopkirk, 50, and Belinda Harter, 49, of Lower Hutt; and Johannes Jordann, known as Chrisjan, 21, of Wellington and girlfriend Alexis Still, 19, also of Wellington.
The Transport Accident Investigation Commission last week said an examination of the accident revealed a strength test on the balloon's envelope and a fuel system inspection were not done correctly, and documentation was incomplete.
It had not determined whether or not maintenance issues were a factor in the accident.
It recommended the Civil Aviation Authority check the practices of hot air balloon maintainers and the airworthiness of the remaining 73 hot air balloons nationwide.
The authority on Wednesday said there were concerns with checks carried out by the engineer responsible for certifying the airworthiness of the balloon that crashed.
It found the engineer, who is responsible for a further 16 balloons, did not conduct maintenance practices according to the manufacturer's specifications. Those balloons were effectively grounded until further checks have been carried out.