Many investors think they need at least $1 million to retire comfortably in the United States. But according to a recent Schoeders survey, only 24% of working Americans expect to cross that threshold by the time they retire.

It can be tough to reach $1 million if you only stash your cash in savings accounts or CDs. But if you spread your savings across a few promising growth stocks, you could potentially turn a $100,000 account into more than $1 million in ten years.

Cash rains down on two happy people.

Image source: Getty Images.

To achieve that, investors should focus on companies that can potentially grow their annual revenues tenfold -- or at a compound annual growth rate (CAGR) of at least 26% -- from 2022 to 2032. That might sound challenging, but I believe three growth stocks -- Rivian (RIVN -7.03%), MercadoLibre (MELI -1.68%), and Twilio (TWLO -4.95%) -- could help generate those millionaire-maker gains.

1. Rivian

Rivian is a producer of electric pickups, SUVs, and delivery vans for Amazon (AMZN -2.29%). Amazon and Ford are its two biggest backers, and it recently partnered with Mercedes-Benz to co-develop electric vans via a new joint venture.

Rivian stands out in the EV market because it went public through a traditional IPO instead of merging with a SPAC (special purpose acquisition company), and it's already manufactured thousands of vehicles while most of its SPAC-backed peers are still struggling to produce a single vehicle or ramp up their production.

Rivian has already produced 14,317 vehicles so far in the first three quarters of 2022, and it plans to produce 25,000 vehicles for the full year. Analysts expect its annual production to nearly quadruple next year as it rolls out its R1S SUV and delivers more R1T pickup trucks and delivery vans, and to continue climbing over the next several years.

Rivian currently has an annual production capacity of 150,000 vehicles, but it expects its annual capacity to reach 600,000 after it opens its second plant in Georgia in 2024. Based on those expectations, analysts expect Rivian's revenue to soar from $1.82 billion in 2022 to $12.19 billion in 2024, which would represent a stunning CAGR of 159%. If it continues to scale up its operations through the end of the decade, it could easily deliver big multibagger gains for investors who ride out its initial volatility. Its stock also looks reasonably valued right now at five times next year's sales.

2. MercadoLibre

MercadoLibre is the largest e-commerce company in Latin America, but it's still worth less than $50 billion, making it a baby compared to Amazon's market cap of $1.2 trillion. But MercadoLibre is growing a lot faster than Amazon, and it could still have plenty of room to expand as income levels and e-commerce penetrations rise across Latin America.

Latin America's e-commerce penetration rate could double from about 8% today to 16% by 2025, according to Fidelity, then jump to 50% over the "next few decades". Americas Market Intelligence also expects Brazil, Argentina, and Mexico -- MercadoLibre's three largest markets -- to grow at CAGRs of 22%, 32%, and 24%, respectively, from 2021 to 2024.

Therefore, MercadoLibre's revenue could easily skyrocket over the next ten years. For now, analysts expect its annual revenue to rise from $10.5 billion in 2022 to $16.6 billion in 2024, which would represent a CAGR of 26%. That growth should also be amplified by the expansion of Mercado Pago, its digital payments platform for on-site and off-site payments.

MercadoLibre is well-poised to generate double-digit sales growth for the foreseeable future as it locks in more shoppers across Latin America, yet its stock still trades at less than four times next year's sales. That makes it a great addition to any retirement portfolio.

3. Twilio

Twilio's cloud-based communications platform handles integrated voice calls, text messages, and other content for mobile apps. Instead of building those features from scratch, which can be buggy and difficult to scale, developers simply outsource them to Twilio with a few lines of code. Twilio then charges the developers usage-based fees to access its platform.

Twilio enjoys a first-mover advantage in this market, and big companies like Airbnb, Lyft, and Stripe all use its services. It's been criticized for relying too heavily on acquisitions to drive its growth in the past, but it still expects to grow its top line by about 30% organically for the next several years as the mobile app market continues to expand. 

Twilio's stock trades at less than three times next year's sales, which is a surprisingly low price-to-sales ratio for such a high-growth stock. It trades at that discount because investors are fretting over its gross margins, which have recently been squeezed by new wireless fees (which are now charged whenever third-party applications access a carrier's network), as well as a higher mix of lower-margin overseas revenue over the past year.

Yet Twilio doesn't seem too worried. It expects its adjusted gross margins to rise above 60% over the long term -- compared to 53% in 2021 -- as it scales up its platform and locks in more apps. If that happens, its profits will stabilize, the bulls will rush back, and it could deliver massive multibagger gains over the next ten years.