Study: Having a best friend is worth over $150,000 in extra income

Why having a best friend is worth over $150,000 in extra income
Why having a best friend is worth over $150,000 in extra income

Studies show that having a friend at work is crucial to your personal happiness and career. But having a strong group of friends outside of work is just as valuable.

A study published in the The Journal of Socio-Economics in 2008 set out to put a price tag on the value of social relationships. The research found that the benefit of having a good friend, from a happiness and life satisfaction perspective, is equivalent to an extra £85,000. Adjusted for inflation, that's roughly £112,000, or $150,000, today.

Nick Powdthavee, research author and professor of behavioral science at Warwick Business School in Coventry, U.K., tells CNBC Make It that though the monetary value may fluctuate over time, the key takeaway still holds true: People who have a rich social network report higher overall life satisfaction than those who don't.

The study analyzed 10,000 people over 18 years, using a dataset from the British Household Panel Survey, to determine what makes individuals happy, money or friendship. Friendship overwhelmingly came out on top.

"Income only plays a small part in influencing our well-being," the study reports. "Other possessions in life such as social relationships ... matter a lot more to happiness than what average level of income can normally buy in the long-run."

Bill Gates and Warren Buffett met in 1991 and have been friends for almost 28 years.
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Respondents were tasked with choosing their level of life satisfaction on a scale of one to seven, with one being very dissatisfied with life to seven being very satisfied with life. Respondents with a rich social network were two satisfaction points higher than those without.

The research also looked at the importance of friendship in relation to marriage. Again, friendship was found to be more valuable.

"On average, people with a rich social network report a significantly higher life satisfaction," says the researcher, "and it has nothing to do with work or marriage."

He then looked at how much money it would take to make someone without a close friend as satisfied as their counterpart, and arrived at $150,000 a year of extra income.

Powdthavee warns that the focus shouldn't be on the monetary number, but rather the day-to-day application of the study's findings. "We have to make trade-off decisions in life," he says, "like more hours in the office or more social interaction."

Choosing to spend extra time in the office, at the expense of your friendships, could be the worse choice in terms of life-satisfaction, he explains.

This is something to consider before accepting a job offer. If you want a job that pays more but reduces your social interactions, you have to be looking at about $150,000 more per year "on top of your current salary," says the researcher.

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