Blue-chip stocks are securities of companies that have been around for a long time, have an established track record, are profitable and are viewed as financially fit. Blue-chip stocks tend to be more stable during a market downturn and they are often the first names to recover when conditions improve. Because of their stability and financial health, blue-chip stocks tend to be millionaires’ preferred stocks as opposed to the more volatile stocks of unprofitable start-up companies. For wealthy investors, blue-chip stocks form the foundation of their portfolio. Look at the holdings of many of the most successful investors and you’ll find numerous blue-chip stocks. Here are three top blue-chip growth stocks to buy now for a millionaire investment strategy.

Apple (AAPL)

Apple (NASDAQ:AAPL) is among the most widely held stocks in the world. Large institutional investors ranging from university endowments to hedge funds own AAPL stock. So too do highly successful, multi-millionaire investors such as Warren Buffett and Ryan Cohen. In fact, Apple is the largest holding of Buffett, who continues to sing the technology company’s praises. Investors large and small like Apple’s product line, its profitability, strong cash position, and the long-term performance of its stock.

Shareholders of Apple also benefit from the stock’s quarterly dividend payment of 24 cents a share, and the fact that Apple buys back more of its own stock than any other publicly traded company. Apple has spent $550 billion buying back its own stock over the last decade, including a $90 billion repurchase in 2022. As for the performance of AAPL stock, it has gained nearly 40% in the last 12 months, risen 288% in the past five years, and its up more than 1,000% since June 2013. No wonder so many people see Apple as a cornerstone of a millionaire investment strategy.

American Express (AXP)

Another major holding of Warren Buffett and many other millionaires’ preferred stock is credit card giant American Express (NYSE:AXP). The company behind the popular slogan “Don’t Leave Home Without It” has been a consistent winner for its shareholders over the past 50 years. AXP stock has gained 21% this year and is up 77% over the past five years despite a difficult environment that included the Covid-19 pandemic and a prolonged suspension of travel, as well as high inflation and elevated interest rates.

American Express is such an established and reliable blue-chip name that it manages to grow in good economic times and bad. This is impressive considering that the company’s business has remained virtually unchanged since the late 1960s. AmEx credit cards remain popular with wealthy individuals who appreciate the lucrative loyalty rewards offered by the company. This has helped American Express continue to grow its annual revenues.

UnitedHealth Group (UNH)

Another rock solid blue-chip stock that is widely held among millionaires and institutions is UnitedHealth Group (NYSE:UNH), the largest health insurer in the U.S. and biggest insurance company by net premiums in the world. The company has annual revenues approaching $300 billion. UNH stock has been a steady long-term performer. Through five years, United Health’s share price has nearly doubled. This year, the stock is down 5%, presenting a buying opportunity for investors.

United Health also pays a strong quarterly dividend of $1.88 per share. And the company consistently posts stronger-than-expected earnings results. UNH’s annual revenue has nearly doubled over the last decade, rising from $144 billion in 2012 to $250 billion in 2022. The insurer’s revenue now surpasses that of JPMorgan Chase (NYSE:JPM), America’s biggest bank. United Health has grown largely through a successful acquisition strategy, with its targets small enough that they encounter little regulatory scrutiny.

On the date of publication, Joel Baglole held long positions in AAPL and MSFT. The opinions expressed in this article are those of the writer, subject to the InvestorPlace.com Publishing Guidelines.