Would you like to retire with a seven-figure nest egg? Most people would, of course, but many people feel such a goal is out of reach with a relatively average income in their working years.

Well, good news: That's just not the case! The key to retiring with $1 million is committing what money you can -- even if it's just a little at a time -- to the market and then simply leaving those investments alone. If you choose wisely, you can stick with a pick for years on end while it makes forward progress.

To this end, here's a look at three core stock picks you can sit on for a few decades in a retirement portfolio.

1. JPMorgan Chase

JPMorgan Chase (JPM 0.67%) is the country's biggest bank, boasting $3.8 trillion worth of assets. It offers everything from consumer checking accounts to corporate fundraising to wealth management.

There's nothing particularly remarkable about its business. Like all its peers, most of its income is interest income earnings by lending money and simply sitting on its customers' assets. It faces the same cyclical ebbs and flows other banks do.

JPMorgan Chase is a shining star within the banking industry, however, by virtue of its sheer size. Not only are its pockets deeper, but its reach is greater. Its size makes it easier for JPMorgan to win new business as it becomes available. There's also the not-so-small detail that it can be difficult for a customer to simply abandon a banking service provider and reestablish a relationship with another bank.

Perhaps the top reason to own a stake in this company for the long haul, though, is its dividend. JPMorgan Chase isn't exactly dividend royalty. It's only raised its dividend payment for 13 consecutive years coming out of 2008's subprime mortgage meltdown in 2011. That's solid, but there are better dividend pedigrees out there.

However, the company's seemingly taking its dividend payments much more seriously than it has in the past. In several years prior to 2008's debacle, the bank didn't raise its annual payout much, if at all. The recent increases haven't been chump change either, growing from 2011's $0.80 per share to an annualized pace of $4.20 per share now.

You can step into this stock while the trailing dividend yield is 2.8%. Since this is a long-term retirement pick, you'll probably want to reinvest these dividend payments in more shares of JPMorgan, rather than just adding them to a cash position in your portfolio.

2. MercadoLibre

It's often called the Amazon of Latin America, and while that description is fair, it's arguably incomplete. MercadoLibre (MELI -2.35%) is also akin to payment platform PayPal, with a pinch of Shopify and United Parcel Service thrown in for good measure. E-commerce, logistics, digital banking, and even advertising solutions are in its wheelhouse. It's a true soup-to-nuts solutions provider.

So why haven't more people heard of it? Because the entirety of its business is aimed at the Latin American and South American markets.

Don't look past the importance of this detail. In many ways, where that region is now is where the North American market was a couple of decades ago, before Amazon evolved into the dominant name it is today. There is no dominant name in the payment and e-commerce arena in this region at this time, opening the door to MercadoLibre to become that leading company.

Up for grabs is a piece of the spending being done by 660 million consumers, many of whom are just now being exposed to reliable internet connectivity. Atlantico's 2023 Latin America Digital Transformation Report indicates penetration of the internet grew from only 43% of households as of 2012 to 78% of Latin American households last year. And like their North American counterparts, these consumers are falling in love with their smartphones, where MercadoLibre does especially well.

The company's clearly capitalizing on the advent of this connectivity too. Last quarter's total volume of merchandise sold via MercadoLibre's platforms soared by 59%, while the total amount of digital payments the company handled jumped by 121%. This growth translated into a year-over-year revenue increase of 69%. That was unusually big growth rooted in pronounced weakness a year earlier. However, analysts are still calling for double-digit sales and earnings growth through next year.

3. Berkshire Hathaway

Finally, if you're looking to become a self-made millionaire retiree, you can't go wrong by riding Warren Buffett's coattails. Owning a piece of Berkshire Hathaway (BRK.A) (BRK.B 0.39%) is an easy way of doing just that. Although Buffett's now got a team of analysts and acolytes helping him manage the $775 billion behemoth, the holding company still has his value-oriented fingerprints all over it.

Sure, value stocks haven't exactly kept up with growth stocks of late. Take a step back and look at the bigger picture though. Until rampant inflation began forcing the Federal Reserve's hand in mid-2022, interest rates had been lingering near rock-bottom lows for years. Now interest rates are at levels not seen since 2007.

It matters simply because low rates favor growth stocks far more than they work in value stocks' favor. Now that interest rates are high again, most value stocks have more compelling investment prospects than most growth stocks. It's a dynamic that could persist for years.

Then there's the other, related reason to step into a position in Berkshire Hathaway for the long haul.

You've likely heard a great deal about Berkshire's top equity holdings, which include big stakes in Apple, Bank of America, Coca-Cola, and several other well-known publicly traded stocks. Did you know, however, that only about half of Berkshire Hathaway's total market cap reflects the value of the fund's stock holdings?

The other half of the portfolio's value reflects the value of dozens of privately held companies, ranging from Geico Insurance to Clayton Homes to Pilot Travel Centers to Fruit of the Loom to Duracell batteries, and more. These are reliable, cash-generating businesses owned at a time when cash flow means much more than it did just a few years back -- when interest rates were markedly lower.

Buffett is still having trouble finding something worth buying with Berkshire's current cash stash of around $157 billion. That's a great problem to have, however, and new opportunities are sure to surface sooner or later. There's no need to rush into a subpar investment.