Many couples have to work through tough money conversations, but that requires both people to come to the table. If one partner refuses to engage every time money comes up, that may be a sign that you’re incompatible.

That behavior, known as “stonewalling,” is the most glaring red flag to look out for when assessing how financially compatible you are with your partner, says Erika Wasserman, a financial therapist and CEO of Your Financial Therapist based in Parkland, Florida.

“If one person’s checked out, it doesn’t work in any part of your relationship — with sex, with religion, with money,” Wasserman says. “If you’re both not willing to work on [financial intimacy] and be open, then it’s time to evaluate the relationship.”

Whether we like it or not, we need money in life, which is why financial intimacy is so important, Wasserman says. A partner who refuses to talk about money early in a relationship will likely continue that behavior, even if you become more emotionally intimate with them, she adds.

“You want someone that’s willing to work on it, that are looking to build that conversation, to be vulnerable with you,” Wasserman says. When you have a partner who is willing to talk about finances, “then there’s hope for the relationship.”