Babies expensive, teenagers more so:

After all, there's the baby furniture, car seats, prams, medical expenses ... the list goes on at the start of a child's life.

But a new analysis has found that while the first couple of years are a stretch on the household budget, the teen age is even more expensive, with costs peaking when a child is 17.

The inaugural Suncorp Bank Cost of Kids Report found that teenagers cost their parents $237 per week, compared with $206 per week for infants, or birth to two year olds.

In those middle years, costs do get cheaper - ages three to four $167 and five to 12 years $163.

"While the fundamental costs for raising children remain the same, new expenses such as mobile communication, broadband, technology used for education and increased entertainment as children become teenagers are costing parents a small fortune," Suncorp Bank Executive Manager Craig Fenwick said, releasing the findings on Friday.

While the cost of raising a teenager exceeds $12,000 per year, it begins to skyrocket for those parents who opt for a private education over the public system.

"On average, the weekly cost of educating a child in the public system is blown out of the water from $18 to $393 if they choose to send their child to a private secondary school," Mr Fenwick said.

"That choice alone is worth the cost of a new car every year, for every child."

As such, he said it is important to have a savings and contingency fund built into the family budget for those unexpected costs associated with raising kids.