The "easygoing'' 50-year-old computer whiz and his 49-year-old partner were among 11 people who died in Saturday's ballooning tragedy near Carterton.
In a statement from his family, Mr Hopkirk's sister Ruth McIntosh said her brother had a kind heart and was deeply devoted to his late wife Pam.
Mr Hopkirk cared for her through her long illness.
"He and his recent partner Belinda were inseparable; together they enjoyed a whirl of outdoor activities.''
They lived together in Korokoro, Lower Hutt, and recently bought a bus which they planned to go exploring in.
"Having just returned from a trip mountain biking in National Park after Christmas, the early morning balloon ride was a surprise gift from Belinda for Stephen's 50th birthday on the 7th of January, something he had been wanting to experience.''
Ms McIntosh said her brother grew up in Ardmore, Masterton and Lower Hutt with a loving family. He is survived by a brother and three sisters.
He attended Naenae College and completed a degree in Botany at Victoria University.
Mr Hopkirk worked for IBM in Petone for many years.
She described him as an intelligent and practical man.
"Stephen could turn his hand at anything from computers to home renovation.''
He was the one his family and friends called on to help them, and he never said `no'.
"His beloved aunty recalls giving him a list of jobs on his frequent visits, which he would graciously work his way through. A real `kiwi' guy, quiet and unassuming but strong and determined.
She said January 7 had always been a special day for the Hopkirk family. The day is Stephen's parents' wedding anniversary for the past 56 years.
"Stephen also shared his birthday with a nephew. Now, it will also be known for the day he died.''
