Tony (51) and Anne (52) Cleveland will receive the Child, Youth and Family excellence in foster care award at Government House.
But Mrs Cleveland said witnessing a change in a child was the greater reward.
''All these kids are damaged and gone through difficult times and you see them change, get more confident and smile - or even start to laugh - and relax, and then you see them doing quite well.
"It's really nice when they start calling your home their home and fitting in and being part of the family. It takes a while, but it is rewarding.''
The couple fostered at their four-bedroom home on nearly 0.5ha of land in Helensburgh.
Inside the home, toys are scattered on the floor, photos of smiling children are on the walls and sports trophies adorn shelves.
In the back yard are home-made rugby posts.
Mr Cleveland, a builder, said the couple had three boys of their own - now aged 29, 28 and 26 - and decided six years ago ''the time was right'' to foster.
Raising children was better the second time, he said.
''Because you know a hell of a lot more than you did the first time.''
Mrs Cleveland said that when her children moved out, she missed the daily routine of raising children, such as taking them to sport and school activities.
''Doing all those things, that if you didn't have kids, you just wouldn't do - it is busy but fun. I love it.''
Child, Youth and Family care and adoptions supervisor Rose Scott, of Dunedin, said the couple were selected for the award because they had fostered 19 children and young people and provided a ''home for life'' for two young brothers and were in the process of providing a ''home for life'' for a young girl.
A home-for-life child was no longer in CYF care and was legally in the care of the family.
The couple had also cared for three mothers and babies, Mrs Scott said.
CYF was always looking for carers, especially for teenagers.
Mr Cleveland said the first child they fostered was a teenage girl.
''It was trial by fire.''
Mrs Cleveland said when the young woman reached an age of independence, she continued to contact the family.
''It is special to know that they are thinking of you on Christmas.''
The awards, hosted by Governor-General Sir Jerry Mateparae and his wife, Janine, Lady Mateparae, were part of foster care awareness week and organised by fostering family support organisation Fostering Kids New Zealand and CYF.
Other award winners in Otago and Southland include Gillian Lynch, of Oamaru, and Lynda and John Mooij, of Invercargill.
Mr Cleveland said he would recommend other people foster children.
People should not be ''scared'' by it.
''You get rewarded every day.''