Women might shack up with a good-looking bloke but when it comes to tying the knot nice guys finish first, new research suggests.

The United States study found that for men, having an above-average personality coincided with a greater chance of marriage.

But for those with better-than-average looks, living with a partner was less likely to lead to wedding bells.

Otago University social psychologist Jamin Halberstadt said the findings were consistent with evolutionary psychology, which distinguished between marriageable men - and short-term mates.

"Crudely put, the distinction is that women are looking for highly fertile men for short-term relationships and highly dependable men for long-term ones. So women have different types of cues."

So while a strong-jawed, classically handsome man is viewed as being a good option for fathering offspring, a less good-looking man with a great personality will be considered a better bet for a stable, emotionally and financially committed marriage.

Researchers in the study examined three personal traits - physical attractiveness, personality and grooming - and weighed up their effect on living with or marrying a romantic partner, using data gathered from nearly 10,000 young adults.

The results showed women choosing who to marry were far more selective than women looking for a live-in lover.

The study also found married people, and those who lived together and eventually got married, were also generally better looking than people who were single or living alone.

"Changing attitudes about the institution of marriage, greater acceptance of alternative living arrangements, and increasing options for women outside the domestic sphere have all influenced how decisions about romantic relationships are initiated and sealed," the authors concluded.

Most research has found men value physical attractiveness and youth more than women when seeking a partner, while women show a preference for earning potential in a man. But it is not all about the looks or riches.

Overall, researchers found the sample group considered the "whole package" when picking a spouse.

Mate selection had also become more egalitarian, with both sexes choosing partners based on broadly similar traits.

The study, subtitled "We'll live with the good looking guy but we'll marry the nice guy", was published in the journal Social Science Research.