You don't need to be sitting on a small fortune to start investing. You can buy some of the market's most compelling growth opportunities for under $20 a share.

Here are three stocks you can get started with now, all priced at $20 or less. All three of these companies have demonstrated tremendous growth in recent years, but they could just be getting started on their long-term trajectories.

So find a spare Andrew Jackson in a coat pocket or under the couch cushions, and let's get started. 

A person lifting dumbells at the gym.

Image source: Getty Images.

1. Xponential Fitness 

Xponential Fitness (XPOF 4.00%) is a monster growth stock trading at just under $20 a share. It is a franchisor that operates a large portfolio of fitness concepts, including Club Pilates, Rumble, CycleBar, Row House, and Pure Barre.  Xponential is growing so fast that it is one of the few growth stocks that have been impervious to the market sell-off this year, posting a 20% gain over the past year while the S&P 500 and Nasdaq Composite are down 17% and 28% over the same time frame.

How fast is Xponential Fitness growing? During the most recent quarter, the company grew revenue 66% year over year to $60 million while adjusted earnings before interest, taxes, depreciation, and amortization (EBITDA) rose an even more impressive 112% year over year.

Even better, Xponential felt confident enough to raise its full-year 2022 guidance to a range of $211 to $221 million in revenue at a time when many companies were reducing guidance. This revenue would be approximately 40% higher than the $155 million in revenue that the company brought in in 2021. The company also bumped full-year EBITDA guidance to $68 to $72 million (up from $67 to $71 million), which would represent monumental 156% growth at the midpoint compared to last year's $27 million in adjusted EBITDA. 

Xponential is growing like gangbusters by inking new deals with franchisees, opening new locations, signing up more members, and finding new concepts to acquire. The company now has 2,357 global studios open, a 21% increase from last year. It boasts 539,000 members, a 32% increase from the year before. 

We've all seen fitness fads that fall out of favor just as quickly as they get hot, but I think that Xponential Fitness can avoid that fate. The company's portfolio of 10 brands should help it to mitigate the downside of any one brand or concept falling out of favor, and the company has been very acquisitive, making nine acquisitions since 2017, showing that it has its finger on the pulse of the fitness industry. Xponential Fitness looks like a great growth stock under $20 that is just getting started. 

2. Bowlero 

With shares changing hands at just under $15, Bowlero (BOWL -1.97%) gives you ownership of one of the market's top under-the-radar growth stocks for well under $20.

Bowlero is the country's largest operator of bowling alleys, and its brands include its namesake Bowlero, AMF, and Bowlmor Lanes. The company also now owns and operates the Professional Bowlers Association as of 2019, making it an all-encompassing bowling powerhouse. And while some investors may not think of bowling as a fast-growing, cutting-edge industry, it has been growing at about a 4% compound annual rate for the past decade. 

In fiscal 2022, Bowlero posted record revenue of $912 million. This represents incredible year-over-year revenue growth of 130%. Revenue is now 31% higher than it was during fiscal 2019, showing that Bowlero isn't just beating easy comps from the COVID-19 time period when many bowling alleys were closed. Bowlero also grew adjusted EBITDA by 81% over the same time frame. 

Bowlero is growing fast because, as the largest operator of bowling alleys in the United States, it is using its scale to roll up acquisitions in a fragmented industry. The company acquired 29 bowling entertainment centers during the course of fiscal 2022, and it has been gaining momentum early in fiscal 2023 with one new acquisition and agreements signed for eight more. 

3. Build-A-Bear Workshop 

I know what you might be thinking -- the last two stocks sound great, but is Build-A-Bear Workshop (BBW 2.39%) really an explosive growth stock? It's a toy store that's been around since 1997. But there's a lot more to the Build-A-Bear story, which is what creates a compelling long-term setup for investors. 

Despite the fact that the company has been around for 25 years, it just posted record revenue in 2021 and record first-half revenue for 2022. Build-A-Bear is proof that a good management team can teach an old dog new tricks, as the company is transforming into an omnichannel powerhouse. Build-A-Bear's digital sales have grown at a whopping 34% CAGR since 2016.

Build-A-Bear management has been thoughtful about how it has built out this digital platform. It knows that families and children love the experience of creating their Build-A-Bear on-site at a Build-A-Bear location and that this is a large part of the brand's appeal, so web sales are more geared toward teen and adult collectors and gift givers, such as a collector buying a Star Wars-themed bear or a spouse buying a gift for an anniversary.

The company is also growing by inking deals with over 75 license partners ranging from pro and college sports teams to Disney, Marvel, and Pokémon. Don't overlook Build-A-Bear, trading at about $15 a share while it is successfully reinventing itself and getting ready for the next 25 years. 

Xponential Fitness, Bowlero, and Build-A-Bear Workshop are all potentially explosive growth stocks with a bright future ahead. You can acquire shares of them today for under $20 apiece, making this the perfect time to start building your growth portfolio with one or all three of these stocks.