You don't need a fortune to invest in the stock market. There are many stocks that trade at less than $100 that can potentially be good investments to build up a position in over time.
Some of the hottest growth stocks to buy right now include Archer Aviation (ACHR -3.21%), Quantum Computing (QUBT -3.11%), and Robinhood Markets (HOOD 2.82%). The stocks have all more than doubled in value in the past year, and I'll break down their opportunities and what their biggest risks are today to help you determine whether these stocks trading under $100 a share are suitable for your portfolio.

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Archer Aviation
In just the past 12 months, shares of Archer Aviation have skyrocketed 192% (as of June 24), propelling its value to around $5.9 billion. The company doesn't generate any revenue yet, but it has been securing deals that could change that.
Its Midnight aircraft is an electric air taxi that aims to change what short-distance travel looks like in big cities. It could ease congestion, and its coming-out party might be the 2028 Olympic Games in Los Angeles, with it already being named the "official air tax provider" for the event.
Entering this week, the stock was trading at around $10, and the biggest risk for investors is that the company may not generate much revenue anytime soon, and its cash burn will accelerate. It has burned through $376.7 million over the past 12 months with its day-to-day operations and will require frequent infusions (i.e., stock offerings) to fund its growth.
Archer is still in the very early stages of building out its aircraft and hopes to be making at least two per month by the end of this year.
It will require a lot of patience, but if you have a high risk tolerance, this investment could still rise further in the future.
Quantum Computing
Next-generation computing is another exciting opportunity that investors have been bullish on. Shares of Quantum Computing are up 2,950% in just 12 months. Given the rising need for greater computing power in the era of artificial intelligence (AI), quantum computers are likely to add a whole new level of efficiency for the tech sector.
Today, the company generates revenue primarily from professional services. But the hope is that in the future, Quantum's cutting-edge machines (which rely on photon technology) and foundry services will transform it into the next big tech stock.
With many other companies also investing heavily in developing supercomputers, competition may be fierce. The biggest risk with the stock is that the company will eventually run out of money.
Over the trailing 12 months, Quantum has burned through $16.8 million in cash from its operations. Its balance of cash and cash equivalents totaled $166.4 million as of the end of March, which provides it with adequate runway for now. But with quantum computers potentially being several years away from the mainstream, this stock still comes with considerable risks and uncertainty.
Quantum Computing stock does have the potential to rise from the $17.52 it's trading around right now, but this is primarily going to be suitable for investors who not only have a high tolerance for risk, but who are also willing to remain extremely patient and are comfortable with lots of volatility.
Robinhood Markets
The least risky stock on this list is Robinhood, which is already generating strong numbers. The fintech's online trading platform, which offers commission-free stock trades, is popular with retail investors. Last year, revenue came in at just under $3 billion, and net income totaled $1.4 billion.
On Tuesday, the stock was trading at around $82, and since the start of the year, the stock price is up about 120%. As excitement has been generated by not just the stock market but also cryptocurrencies, trading levels have been elevated, and investors may be anticipating lots more growth for the company in both the near term and over the long run.
With the company's market cap of nearly $70 billion, the biggest risk with the stock is that it may be a bit expensive. It trades at 44 times its trailing earnings, which means that expectations are high.
But with the business growing at an impressive 50% year over year through the first three months of 2025, the premium may be justifiable. If Robinhood Markets continues to deliver strong growth while padding its earnings along the way, there can still be room for the stock to climb higher.