A worker mows the lawn of the British Consul General's home in California. It’s a prime example of how people who have money can use it to save them time. (AP Photo/Nick Ut)

You’re counting down until payday, waiting for the moment when a direct deposit turns your bone-dry bank account into a lush oasis. But what should you spend your hard-earned money on? Fancy dinners? The new iPhone? Avocado toast? We talk with Harvard Business School associate professor Ashley Whillans, who says that if you truly want your money to make you happier, consider spending it on things that will save you time.

Three Takeaways 

• You don’t need to spend tons of money on time to see gains in happiness. Whillans says her research found changes in mood occurred when people spent as little as $40 on freeing up time.
• So why don’t we spend more money on time? We’re not very good planners. We always think we’re going to have more time than we actually do. Researchers call it the "Yes-Damn" effect.
• Spending money on time can spruce up your relationship! In heterosexual couples, Whillans is currently collecting data that found that women benefit from time-saving purchases, like cleaning, more than men. But in a sort of domino effect, the research also found that men feel the positive effects when women benefit.

More reading 

• A Chicago Tribune columnist wonders whether buying time is smart or just lazy.
• Business Insider looks at the top three things Americans spend money on.
• NPR examines how retailers are reacting to the ultimate timesaver: online shopping.