Planning a wedding? Finance expert recommends planning a 'pre-prenup' conversation to create a financial operating agreement.

• A prenuptial agreement, also known as a "prenup" is a set of expectations for the division of assets and finances in the event of a divorce, separation, or death of a spouse.
• There are several factors that may make getting one more appealing or necessary for millennials such as debt and family experience with divorce.
• Cynthia Loh, vice president of digital advice at Charles Schwab, says that one way to talk about getting a prenup or creating an alternative plan for one is with a "pre-prenup" conversation.

Planning a wedding is a substantial financial endeavor, but it's nothing compared to how much a couple compromises financially throughout a marriage. Money is one of the biggest causes of divorce, but many still enter into it without a clear view of their partner's expectations — let alone a financial plan. People who have a financial plan feel more confident about reaching their goals, yet according to our research, only 34% of millennials have one.

Modernizing the prenuptial agreement

It might sound counter-intuitive, but one way to spark a conversation with your partner about a financial plan is by discussing a prenuptial agreement. The word "prenup" may cause anxiety, but it can be a great tool to guide a conversation about each of your visions.

A couple doesn't even have to go through with a prenup to reap the benefits. Talking about one will inspire conversation about financial goals, assets, liabilities, income expectations, future (or current) children, and other topics that are best to cover before marrying. This is particularly important for millennials because:

• Millennials marry later in life – Over the past decade, we've seen an increase in the average age of Americans tying the knot as Millennials prioritize careers and societal norms shift.
• They carry higher levels of debt – Millennials come into a marriage with more debt from student loans and credit cards. Some also have more wealth accumulated from working and investing before marriage, meaning even more need for a plan.
• They're familiar with divorce – Many millennials have experienced divorce through their parents, with divorce rates much higher among older generations, and they know the financial difficulty it can cause – especially without a plan before marriage.

Having 'the talk'

Whether you opt for a prenup or not, talking about one can be a productive way to create a financial plan. Here are three topics to address in any 'pre-prenup' conversation:

• Find out each partner's financial situation – Do you carry debt? How will you pay it off? Does debt become a joint responsibility? Discuss any existing liabilities and assets, then establish what is owned individually vs. jointly.

• Share how you envision the future – Having a clear conversation about shared goals – and how you'll handle situations where you diverge – is critical. Decisions around your careers, or someone potentially staying home with children, will impact each of your futures.
• Decide if it's time for professional guidance – Be realistic about whether you can create a long-term plan that meets both of your needs on your own. Whether you find a financial advisor or a digital planning tool, there are many helpful resources.

A business school professor once told my class that choosing your partner is the biggest investment decision you'll make. You would never invest in something without talking about the terms of engagement, so why enter a marriage without laying out a concrete financial plan?

Having these conversations can help you and your partner avoid future conflict and feel confident that you've laid a strong foundation for communication that will enhance your marriage long after saying "I do."

This article was contributed by Cynthia Loh, vice president of digital advice at Charles Schwab, and a member of BI's Money Council.