Being single can be more expensive, but have you ever wondered how much?
Data shows the "single tax" - or the additional cost of doing life alone - varies over the course of a person's life.
Here's how the numbers stack up:
Working age
Economist Shamubeel Eaqub compiled data that showed, for people aged 25 to 49, single people were spending 14 percent more than their coupled counterparts.
The biggest differences were in housing - where they spent 53 percent more, health, where they spent 40 percent more and communication, where they spent 41 percent more.
Shirley McCombe, of Bay Financial Mentors, said it was "much" more expensive to live as a single person, especially if someone wanted to live alone.
"Trying to service a mortgage or pay rent on one income is very difficult and it is not just a matter of finding a one- or two-bedroom place as these are not necessarily proportionally cheaper and they are hard to find."
The Retirement Commission said couples were more likely to say they were financially comfortable, significantly less likely to experience the most common types of financial stress and more likely to have savings and investments as well as insurance.
Couples had more debt but that was probably because they were more likely to own homes.
They were less likely to say they were worried about their finances from pay to pay and more likely to say they could cover an unexpected expense.
Brad Olsen, chief executive at Infometrics, said Stats NZ data showed a one-person household in 2023 spent an average of $807.90 a week compared to $1611.30 for a couple.
"Overall, couples spend about the same per-person as a single person, but what that spending goes towards is quite different.
"Housing costs is the key area where costs can be lower for a couple. Sharing a bed means you can spread the cost of housing across two people in a couple. Single households spent $263 a week on average on housing and utilities, compared to $184 per person for those in a couple. That nearly $80 difference per week is money that couples can use to spend on other areas."
That was often going on things like transport and food.
"[Food spending was] $140 per person per week for couples versus $132 for a single person. Clearly the food need for a single and a person in a couple should be the same, so the additional spending implies that in saving in other areas of life like housing, those in couples have more money left over to spend more, or get higher quality or more luxury/non-necessary items."
Between the ages of 50 and 65, single people spent 11 percent less but still spent 53 percent more on housing and household utilities.
Single parents face additional challenges.
Retirement Commission research lead Jo Gamble said people should ensure they were getting the full government support available to them. Working for Families, for example, operates on a household income basis so single people could be more likely to qualify.
But it also creates higher marginal tax rates.
A recent Treasury paper found 13 percent of two-parent households and 30 percent of single-parent households were paying effective marginal tax rates of more than 50 percent.
For a single parent earning a median wage of $33 an hour in the 2025 tax year, working between eight and 20 hours a week would mean they only kept 10c of every additional $1 earned because of tax and the reduction in benefits and Working for Families credits they could receive.
Pre-retirement
In the five years just before retirement, single people were spending 9 percent less than couples, according to Eaqub's data, but 35 percent more on housing and utilities.
This is a time of life when many people are saving for retirement and a financial shock could be a big problem.
Gamble said the fact single people were more likely to report not having insurance or savings meant they could be financially exposed.
"From the Retirement Commission's perspective there are two prongs to work towards- financial goals and financial resilience.
There does seem to be an indication single people struggle on both of those... If you're part of a couple and one of you loses your job you're less vulnerable."
Retirement
Single people receiving the pension get about $520 a week after tax when they live alone, but couple get about $800 a week.
Research from Motu found a third of retired households were single people living alone and 15 percent single retirees living with others. Single people were more likely to be renting than to own their own homes.
Singles had total discretionary spending of $8523 a year compared to $24,461 for couples.
"This suggests that couple-only households spend more in per capita terms because they seek higher standards of living rather than due to diseconomies of scale in shared living."
Massey University's retirement spending guidelines show a single person living alone would spend $687 a week on a no frills lifestyle in a metro centre compared to just over $900 for a couple. In a provincial centre, they spent $564 compared to $1031.
For a choices life, they would $768.76 in metropolitan centres compared to $1739 for couples, and $752 a week in provincial areas, compared to $1210 for a couple.
Report author Claire Matthews said the extent to which it would cost more to be single would depend on the individual and their circumstances.
"There are certainly some economies you can make as a couple - you don't have to double everything. If you look at power, for example, if you're heating a room it doesn't matter whether there's one person or ten people in the room, it's going to cos the same."
But she said there could be other ways that being single was cheaper.
"It's one of those things where I don't think it's black and white."
