Your non-negotiables, before you get serious

A non-negotiable is something you would end a relationship over, not something you’d simply prefer. Most lists are too long. The ones that hold up are short, usually five items or fewer, and get raised in the first month or two, before you’re invested enough to talk yourself out of them.

What counts as a non-negotiable?

The useful test is plain: would you leave over this? If the answer is “I’d be disappointed, but no,” it’s a preference. Preferences are fine. They just belong in a different column.

For many people in their forties, the short list tends to include things like:

• Children. Whether either of you wants them, or more of them, and how you each parent the ones you have.
• Honesty. Including about money, past relationships and health.
• How conflict goes. Whether disagreements get worked through or turn cruel.
• Substances. Drinking or drug use you can’t live alongside.
• Where you live. If one of you can’t move and the other has to.

Why do dealbreakers carry so much weight?

Because people react more strongly to a bad trait than to a good one, especially when they’re thinking long term.

In six studies with more than 6,500 people, psychologist Peter Jonason and colleagues found that dealbreakers counted more against a potential partner than dealmakers counted in their favor.1 Dealbreakers were also stronger when people were thinking about a long-term relationship than a short one.1

So it’s normal that one item on your list can outweigh three lovely qualities. That’s how most people are built. The question is whether the item really belongs there.

Why does a short list work better?

Long lists tend to fill up with preferences: height, income, a shared love of hiking. Research on what people say they want versus how they actually respond suggests some of those matter less in person than on paper.

A large review led by Paul Eastwick pooled 97 samples. A partner’s earning prospects had only a small association with how romantically people rated them.3 Physical attractiveness had a much larger one.3 In other words, some résumé items you’d write down may not move you much when someone’s sitting across the table.

A short list keeps your attention on what you’d actually leave over.

Why do non-negotiables slip?

Mostly because of how you feel at the time you’re tested.

In a 2022 pair of experiments, Jonason’s team found that people grew less interested in someone once they learned about a dealbreaker.2 But people who were lonelier, or had lower self-esteem, were more receptive to partners with dealbreakers.2

That’s worth knowing. A lonely winter, a hard custody season, or a bruising divorce can make it easier to let something slide that you’d never have accepted a year earlier. That isn’t weakness. It’s a reason to write the list down when you feel steady, and check it when you don’t.

Renata, 46, a hospital pharmacist with two teenagers, had one firm line after her divorce: honesty about money. Four months into seeing Gideon, she learned he’d borrowed from his brother and hadn’t mentioned it. Her first instinct was to let it go. She’d been lonely, and he was kind. She raised it instead, on a Saturday when the kids were at their dad’s, and asked what else she didn’t know.

When should you bring them up?

Earlier than feels romantic. Many people raise one big topic by the fourth or fifth date, and the rest within the first couple of months.

• Kids: often first, especially if you have them.
• Honesty and money: when something comes up naturally, like splitting a trip.
• Conflict: after your first disagreement, by talking about how it went.

Your list may change as you do. That’s fine. For more on how this decade shapes dating, see what’s different about dating in your 40s, and when you’re ready for the next step, how to ask about exclusivity.

What the dealbreaker research covers, and doesn’t

• Jonason’s studies mostly asked people to react to hypothetical partners, not ones they were actually dating.12
• The meta-analysis looked at traits like attractiveness and earning prospects, not the deeper items on most lists.3
• None of the samples were limited to people in their forties.
• The sorting game reflects common views; your own list can sort differently.
• Renata and Gideon are illustrative characters.