Naming parties are replacing christenings as families further remove religion from significant life milestones.
Dougal and Hayley Marks said they chose a non-religious celebration when their son Oscar, now 5 months old, was born.
"My husband is a Jew and I'm an atheist so we didn't want to go to a church - it seemed weird - but we still wanted godparents," Hayley said. "It feels like an empty role without a ceremony, so we wanted to talk about the reasons we'd chosen them."
Celebrant Penny Ashton said she's noticed an increase in the number of people opting out of religious rites at occasions such as weddings and baby namings. "They generally just say, 'We don't want it to be religious because we're not religious."'
This reflects a decline in people ticking the "Christian" box at Census time. In 1961, 89.9 per cent of the population identified as Christian but that dropped to 70 per cent by 1991. In 2006 it was 52 per cent, and this year's Census is predicted to reflect a continued decrease.
Baptisms declined even faster over the same period. In 1961 there were 4401 infant baptisms in the Auckland Anglican diocese, in 1990 there were 1418, and by 2011 the number had dropped to just 452. Catholic baptisms have risen over the past five years, as the church has been bolstered by immigrants.
Peter Lineham, associate professor of history at Massey University, said the pull of religious tradition was still there for some people.
"Even after you weren't required to belong to a church, still the minimum that was expected was that you were christened, married and buried in the church," said Lineham.
Hayley Marks said going to a church for a traditional christening would have felt like cheating.
"We hadn't really been to a church, ever, so it just seemed a bit weird," she said. "I loved the idea of it, but it would have felt fraudulent, like being a fair-weather friend, almost."
One of Oscar's godparents was religious, but Marks said she'd had no objection to a secular ceremony.
"We still use the word godparents, I don't mind having that level of involvement, but that's as far as the religious element goes."
Marks said family was the main focus of Oscar's celebration.
"All the people who are special to us got to talk. My Dad gave a speech, and everyone gave advice to be read out at his 21st. It's almost like a 'welcome to the family' ceremony."
Anglican Bishop of Auckland Ross Bay said there had been a decline in church attendance but he believed those who did take part were more focused than before.
"We don't encourage people to have their children baptised unless they're really serious about what it involves. So in a sense it's about the church taking itself more seriously.
"We're dealing with smaller numbers, but now we're dealing with people who are here thoughtfully and have made a conscious decision about being here.
"It marks a shift to a secular society. Within that, people are still looking for rituals to take part in, which represent the integrity of who they are."
• 4,401 in 1961
• 1,418 in 1990
• 452 in 2011