But little of it left behind here will go to those perhaps most in need, with New Zealand ranking low internationally when it comes to leaving charitable bequests.
A report from financial advisors JBWere estimates inheritances of around $27 billion in 2024 will grow, totalling $1.6 billion in transfers by 2050.
Lead author John McLeod told RNZ's Nine to Noon on Tuesday it was a "fairly easy equation".
"It's the number of people dying, and we're fairly good at counting that - about 37,000 per year in New Zealand - and the average wealth of those who are likely to die, which sits about $750,000, so you put those two together and you get $27 billion.
"That, 37,000 per year currently was only 27,000 20 years ago, and it's going to move to 66,000 in another 50 years, so you can really see it coming through in the number of people passing away. Between now and 2050 it'll be $1.6 trillion. It's a massive total."
He said New Zealand was a relatively wealthy country per capita - about seventh in the world, and despite growing inequality, was still fourth for median wealth.
"If you compare that to somewhere like the States, which has got a lot of wealthy people, they move from number four on average down to 14 on median. So your wealth is spread - while there's inequality, it's spread more evenly and that's good for the potential of bequests and average passing on in dollars."
Only 1.3 percent of wealth passed on from the deceased in New Zealand went to charitable organisations, McLeod said, "a fairly low number globally", with almost 99 percent going to partners and eventually, children and other family.
"So even if we were to see a doubling of that, it's still saying that 97 percent will stay with kids or family, so I don't think it's going to bite into it dramatically, it's just that the level left to charity is relatively low in New Zealand and Australia."
JBWere has a Philanthropic Services division which "helps 'for-purpose' organisations and philanthropic groups to deliver on their mission" through advice, education and investment governance.
McLeod said part of the problem was that wills were generally altered very few times in a person's life, charity not always front of mind.
"I think when we think about leaving a will or writing a will, we probably do it three times in our life at significant times. And so you're sitting with a solicitor for maybe an hour, three times in your life - so unless charity's forefront of your mind, you just want to get out of there. And they ask, 'How many kids have you got?' and you divide things by that number.
"I think if you think of things a little more broadly - and we're seeing this with a lot of the families we speak to, albeit slightly on the wealthier side - they're thinking about trying to pass on more than those assets. So they're thinking about, how do we pass on the values, the knowledge, the community connections, the things that have given us importance in life? And by having the families involved in their giving and their community connections earlier and adding something to a will, even if it's only 3, 4, 5 percent - which is, you know, three, four, times what happens now - that's really adding the, adding to the purpose that their children are going to have in life following that.
"So we actually think, when you think of the full family balance sheet including more than just the dollars, you're actually enhancing the kids' lives by getting that connection earlier. And you're really not cutting into the total dollars that they're having by any significant amount at all."
The amount going to charity will likely triple to about $1b over the next 20 years as more Boomers died, leaving behind larger amounts of wealth, but McLeod said that could
Currently about $320 million was left to charities in New Zealand annually, McLeod said, which "isn't bad" but could be $1 billion if the average bequest rose a few percentage points, because more people will be dying and leaving behind larger amounts of money.
"But if we could increase that 1.3 percent to 2 percent, 3 percent, you're talking about a tripling of that total value. That's highly significant for a charity sector that has total philanthropy around the $4 billion a year mark. If we can be adding $3 billion going out 20 years just from bequest, that's a significant addition and that improves the quality of life of all of us."
