Gen Zers and millennials are currently rewriting the traditional money rules. Here are five examples, plus my best advice for communicating about money:

1. Keeping financial secrets

Almost two-thirds (63 percent) of Gen Zers (between ages 18 and 26) who are married or living with a romantic partner have committed financial infidelity against that person, according to a recent Bankrate survey.

At 54 percent, millennials (27 to 42) aren’t far behind. Yet only 29 percent of Gen Xers (43 to 58) and baby boomers (59 to 77) have done so. We’re talking about money secrets such as spending more than the other person would be okay with, harboring secret debt or maintaining an undisclosed credit card or bank account.

Strikingly, young adults are not only the most likely to commit financial infidelity — they’re also the most likely to say it’s worse than physical cheating. Maybe they got caught and their partner didn’t react well. More than 1 in 5 Gen Zers (22 percent) and millennials (21 percent) say money secrets are worse than physical infidelity, compared with just 5 percent of boomers and 4 percent of Gen Xers.

2. Separating their finances

Gen Zers in live-in romantic relationships are more than twice as likely as Gen Xers and boomers to maintain completely separate financial accounts from their partner (43 percent versus 19 percent and 18 percent, respectively; millennials came in at 31 percent). Only 26 percent of Gen Zers and 33 percent of millennials completely combine their finances with their significant other, versus 45 percent of Gen Xers and 50 percent of boomers. The rest have a mix of joint and separate accounts.

Many people like the independence of having at least some money they can claim all to themselves. Perhaps it’s for retail purchases, hobbies, nights out with friends, gifts or something else. I think that’s totally fine as long as you both agree upon the parameters ahead of time.

If you and your partner agree that you each get a certain dollar amount from every paycheck that you can spend no questions asked, then go for it — but don’t squirrel money away without the other person’s knowledge. It’s hard enough to meet your financial goals when you’re working together. It’s almost impossible if you’re pulling in different directions. And the breach of trust associated with secret spending or a clandestine account can be even worse than the act itself. It’s hard to get that trust back once you’ve lost it.

3. Delaying milestone events

Among people getting married for the first time, the median ages are 30.4 for men and 28.6 for women, the Census Bureau reports. In 2000, those figures were approximately 27 for men and 25 for women. Way back in 1947, they were 23.7 and 20.5, respectively.

While there are many potential explanations, the economy is among them. A 2022 Bankrate survey revealed that 14 percent of Gen Zers and 13 percent of millennials delayed getting married specifically because of economic issues. Only 4 percent of Gen Xers and 1 percent of boomers said the same.

Many couples are also pushing back their decisions to have children. The median age of a mother giving birth hit a record-high 30 in 2019, up from 27 in 1990, the Census Bureau reported. The aforementioned Bankrate survey found that 15 percent of millennials and 14 percent of Gen Zers delayed having children explicitly because of money matters, compared with a mere 3 percent of Gen Xers and 1 percent of boomers.

4. Buying homes before they’re married

Interestingly, Americans may be getting married later, but they’re not letting it hold them back from homeownership. About a third (31 percent) of all U.S. adults — and a whopping 41 percent of 18- to 34-year-olds — have bought a primary residence with someone they aren’t married to, according to Realtor.com data.

This new money rule makes me nervous. If you plan on buying a house with a romantic partner before you’re married, I think you should be especially careful about how the mortgage and property deed are structured. If the relationship doesn’t work out, you need clear guidelines on what happens to the home. Will you sell it and split the proceeds equally? Will one member of the couple continue to live in the home and buy the other out? It can be a murky issue, especially if you’re not married, so be very intentional about covering your bases before taking the leap into unmarried homeownership.

5. Sharing financial details

More than 4 in 10 U.S. adults said that knowing someone’s credit score would impact their interest in dating that person, a 2017 Bankrate study uncovered. That included 50 percent of women and 35 percent of men (42 percent overall). Older millennials were the most likely to say credit scores would impact their dating habits.

Salaries are another formerly taboo topic that young adults are bringing into the light. Forty-two percent of Gen Z workers and 40 percent of millennials have shared their salary information with a coworker or other professional contact, compared with 31 percent of Gen Xers and 19 percent of baby boomers, according to a 2022 Bankrate survey.

The bottom line

Society is constantly evolving, and the old rules need not always apply. Gen Zers and millennials are getting married later and are more likely to be members of a two-income couple. There can be positives to that, but I also see evidence that a lot of young adults are having trouble meshing their money personalities with their partner’s.

If you don’t get married until your 30s and have lived and worked independently for more than a decade, it’s understandable that you might be a little set in your ways. Relationships take work, so just like you need to coexist with your partner’s beauty products taking over the bathroom or dirty dishes stacking up in the kitchen sink, you need to find sources of commonality and compromise when it comes to your financial habits.

My best advice is to communicate early and often about money. Start small, maybe by setting a timer for 10 or 15 minutes and chatting briefly about upcoming bills and money that’s coming for the month.

Over time, aim to discuss deeper topics such as your money values and goals. Try to check in about your finances at least every few weeks. It’s great if you can get to a place where you’re pulling in the same direction toward something you both want, whether that’s a bucket list vacation, buying a house, retiring early, saving for your kids’ college education or something else. The more you talk about money, the easier it should become.

But you need to flex those figurative muscles first. Most people aren’t particularly comfortable discussing money matters, so you need to build up to it gradually, similar to an exercise program.

Have a question about credit cards? E-mail me at ted.rossman@bankrate.com and I’d be happy to help.