Long-term investing is the way to go if you aim to build wealth, and that means holding stocks for at least five years. But there are some companies that you'll want to hang onto for much longer, and in certain cases, you may never want to let them go. These companies may be industry leaders or have unusual brand strength. Or they might have enormous selections of products that promise revenue as far as the eye can see.

These sorts of businesses make great additions to your portfolio because, over time, they're likely to offer significant earnings and share price growth. And the great news is you don't need thousands of dollars to start investing in some of these companies. In fact, you can buy at least one share of the following forever stocks with just $100.

Mickey Mouse stands in front of Sleeping Beauty's castle.

Image source: Disney.

1. Disney

Disney (DIS 0.25%) owns the world's most-visited theme parks, produces blockbuster movies, and is on track to bring its streaming service to profitability by the end of its fiscal 2024. The company has stumbled in recent times due to rising costs, partially linked to its investments in its streaming services.

But Disney may be about to enter a new phase of growth. Longtime CEO Bob Iger, who grew earnings and the share price when he originally held the role, is back. And after about nine months on the job in his new stretch, he has already put Disney on course to surpass his cost-savings target of $5.5 billion.

Iger also plans to scale back on the number of movies Disney produces to focus on those likely to be most successful, and he aims to shift ESPN to streaming to revive growth at the sports network. Meanwhile, Disney's park, experiences, and products business drives revenue -- and its brand strength means this is likely to continue.

Considering all of this, Disney stock -- trading at 22 times forward earnings estimates and down from more than 30 earlier in the year -- is a steal today.

2. Pfizer

Pfizer's (PFE 0.56%) vast selection of products -- and its promising pipeline -- make this pharmaceutical giant a potential long-term winner for your portfolio. We've all heard a lot about Pfizer in recent times thanks to its coronavirus vaccine and its antiviral COVID-19 treatment. Those products helped push its revenue above $100 billion last year -- a record for the company.

COVID-19 vaccine sales are on the decline, but as that trend weighs on Pfizer stock, we shouldn't worry. Instead, we should see this as a buying opportunity.

That's because Pfizer, like Disney, is heading into a new chapter of growth. The company right now is halfway through a key 18-month period during which it expects to bring 19 new products or indications to market. Pfizer expects revenue from these to start rolling in during the second half of this year.

Pfizer also expects its pipeline and new business development deals will add significantly to its revenue in the coming years, potentially resulting in non-coronavirus-related revenue of $84 billion by 2030.

That's why, today, trading for only 10 times forward earnings estimates, Pfizer looks cheap -- especially compared to some of its big pharma rivals.

PFE PE Ratio (Forward) Chart

PFE PE Ratio (Forward) data by YCharts.

3. Coca-Cola

Coca-Cola (KO 1.92%) offers investors a certain sense of security. The company's brand strength and presence around the world are a couple of reasons to be optimistic about its future. As the world's largest non-alcoholic beverage maker, it sells drinks -- the eponymous Coca-Cola as well as juices like Minute Maid and other well-known products -- in more than 200 countries.

The beverage giant's constant innovation and plans to expand its presence in developing nations mean Coca-Cola hasn't reached its limit when it comes to growth. Meanwhile, the company has managed to grow recently, even in a difficult economy, with revenue and earnings per share climbing last quarter. Coca-Cola even increased its revenue guidance for the year.

Coca-Cola is also a Dividend King, with a more than 50-year track record of annual payout hikes. So, you can count on the stock for passive income. And with free cash flow on the rise -- and rebounding in recent times after a dip -- it's clear the company has what it takes to keep the dividend growth going. And that means a small investment in this stock today could help take your portfolio a long way over time.