People start side hustles for many reasons. More than a quarter, 27%, use their side hustle income to pay bills and expenses, 48% use it for extra spending money, and 10% use it to save for a goal or major purchase, according to a May 2020 DollarSprout survey of 698 U.S. adults.

For people in their 40s, generating extra income to put away for a comfortable retirement could be top of mind. "A lot of people are worried because when they were in their 30s," says Kathy Kristof, founder of Sidehusl.com, "there were so many things that they had to buy or pay off, like their education, that they got a late start on saving for retirement."

"Adding a little extra income at this moment in time can really help you make up for lost time," she says.

Here are five hustles for people in their 40s to consider.

Rent out used baby gear

Many 40-somethings are parents to young children or even teenagers. And a lot of them may be stuck with baby clothes, toys, and equipment they don't know what to do with. "For those who still have all of their baby equipment sitting in the garage," says Kristof, "there's a site called BabyQuip that will allow you to rent that out."

BabyQuip is designed for traveling parents who don't want to lug all of their gear around when they go on a trip and instead prefer to rent the essentials from other parents. Equipment on the site includes high chairs for $10 per day, strollers for $11 per day, and cribs for $24 per day.

There is a $200 fee to start and the site keeps 20% of your profits. Providers, as those who rent out their equipment are called, earn an average of more than $600 a month, according to the site.

Consult in your field of expertise

By their 40s, a lot of people have some sort of work background or experience, so "this is an ideal time to look at consulting in that field," says Kristof.

If you managed a restaurant, for example, you could consult other restaurants on how to do so efficiently. If you started a successful Etsy shop, you can consult other virtual store owners about that.

Consider where your expertise lies and what you could teach people, then reach out to some potential clients with your offer to help. "You can charge $2,500 to $5,000 for a half-day workshop on something that you know," Angelique Rewers, founder of BoldHaus, a consulting firm that helps small businesses land corporate clients, previously told Grow. "You build it once and you sell it over and over and over again."

Video by David Fang

Do some freelance writing

If you are skilled at writing, there are plenty of companies that could use your skills to write their various marketing materials. "The internet runs on a ton of content," says side hustle expert Michelle Jackson. "Companies only have so much capacity to facilitate that" with their in-house staff.

Consider offering your services to write blog posts, social media posts, newsletters, and website content on sites like Upwork and Fiverr, or looking for freelance writing gigs on FlexJobs. Freelance writers on Upwork charge between $35 and $100 per hour.

"Whether you're single or you have littles," says Jackson, "you can write that content whenever you feel like it based on a deadline" you agreed on with that company.

Rent out your space

By your 40s, you may have had the time and the means to upgrade your living situation, as a result of which you may have ample space to rent out to others. Whether you live in a sprawling mansion or a condo in the middle of the city, consider renting out your space on any of the following platforms:

  • SabbaticalHomes.com enables homeowners to list their houses for rent for days, weeks, or months at a time. An apartment in Cambridge, Massachusetts, is currently renting for $650 per week, and a home in Philadelphia is currently renting for $2,500 per month. There is an annual $85 listing fee (unless you're an academic, in which case the price is $60) and a $50 fee for every "match" made on the site.

Video by Stephen Parkhurst

Sell photos of your kids' events

If you frequent your kids' soccer games, ballet recitals, robotics tournaments, and so on, consider snapping a series of photos of them, then posting them on sites like Snapped4u for other parents to buy and download.

Snapped4u enables photographers to create accounts on which they upload photos for purchase, with a limit of $20 per photo. The site takes a $10 registration fee, as well as $0.50 per photo for photos priced $5 or less and 10% of the price on photos priced higher than $5 for U.S.-based accounts. Non-U.S.-based accounts must pay a $0.60 fee for photos priced $5 or less and a 12% fee on photos priced more than $5.

One thing to keep in mind when you're taking on a side hustle, says Jackson: Your capacity. "As we get in our 40s," she says, "we have all of these different things that we're managing, like family members, children, our own personal selves, parents." Consider how much time you really have available every week and how much time each of these hustles could take so you don't overextend.

"I think that capacity is a key part of saying yes to a project," she says.

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