The couple entered the promotion when taking out a debt consolidation loan with NZCU Baywide.
"We visited the branch in Napier to get a better rate so we could save money, and now we've won this amazing prize - we are so very grateful - I cried when I found out.
"Honestly, this could not have come at a better time as it's been an expensive year so far.
"We've had two wonderful weddings for close friends and our daughter is just about the turn 21 so we're having a party. We also usually have to save up for winter to cover the extra cost of power, so this prize is absolutely going to help out."
NZCU Baywide sales, marketing and channels general manager Andrew Quayle said the promotion was special because it removed the pain of paying bills for a while, provided an ongoing benefit and allowed a bit of financial freedom over winter.
"The prize money is split between $2000 for groceries, $1500 for petrol and $1500 is credited onto the winner's power account.
"This time of year is always more expensive for families as they prepare for winter. We are rapt to be able to provide some extra help so they have some leftover cash to spend on other things."
The promotion was open to any NZCU Baywide customer who took out a personal loan over $2000 between February 1 and April 30, 2018. The winner was drawn randomly from all those who had loans approved and drawn down across the 16-strong branch network, as well as online applications received nationwide.