Owning a stock for life requires patience and conviction, but the idea of earning regular passive income in the form of dividends can make it more alluring. Just reinvesting those payouts could give you a big leg up in your efforts to grow the value of your portfolio. 

How consistently a company pays and boosts its dividend, however, can make a big difference to your returns, so when choosing long-term income investments, you should cherry-pick companies that have demonstrated the attributes that will allow them to keep growing those payouts for years, and even decades.

If you're wondering where to find such dividend stocks, here are three that could pay you well for the rest of your life. 

A top-notch Dividend King to hold forever

Over the course of 181 years, Procter & Gamble (NYSE:PG) has built a massive business empire. Today, it boasts a portfolio of 65 brands, most of which are globally renowned household names such as Pampers, Oral-B, Gillette, Crest, and Vicks. In fact, the consumer products behemoth owned 170 brands until around five years ago, when management decided to slim the business down, cutting out low-margin products to build a leaner, more profitable portfolio.

In the intervening years, the company also made some big growth moves, including the $4.2 billion acquisition of Merck's consumer health business. P&G generated $71 billion in sales in its fiscal 2020, which ended June 30. The fabric and home care category (with brands like Tide and Swiffer) was the largest contributor, accounting for 33% of P&G's sales and 31% of earnings.

A dollar bag with hourglass beside a rising bar graph, denoting income growth.

Some dividend stocks can earn you extra income for a lifetime. Image source: Getty Images.

Because its daily-use products enjoy resilient demand, P&G has been able to generate large amounts of cash flow that it has doled out to shareholders. It has paid a dividend for 130 years, and increased its payout annually for 64 consecutive years. That has earned it a place among the rarefied class of Dividend Kings.

P&G just delivered a strong fiscal first quarter and upped its outlook for the full fiscal year. The stock currently yields 2.2% and the company expects to pay out $8 billion in dividends in the year. With management laser-focused on margins, cash flows, and dividends, income investors can count on being able to sit back and collect good payouts from P&G year after year.

A proven dividend payer you can rely on

Most utility companies pay dividends -- but no other utility has a track record quite like Consolidated Edison's (NYSE:ED): It increased its dividend for the 46th straight year in 2020. That's the longest such streak among all the utility stocks in the S&P 500. And management has picked up the pace with its payout hikes in recent years. The company grew its dividend at a compound annual rate of 3.3% between 2016 and 2020, compared with only 1.8% in the previous five years. You'd be astounded to see what a massive difference growing dividends can make to a stock's total returns over time.

ED Chart

ED data by YCharts

Con Ed provides electricity, natural gas, and steam services to 10 million customers in New York City and Westchester County. With New York now setting an ambitious target of generating 70% electricity from renewables by 2030, can Con Ed be far behind? Already, 71% of the company's current generating capacity is comprised of renewable energy sources, specifically solar and wind. Con Ed is, in fact, the second-largest solar power producer in North America.

Also, it aims to convert 100% of its light-duty fleet to electric vehicles by 2040 and pump $1.5 billion into energy efficiency projects by 2025 to meet state targets. That's over and above the billions of dollars it'll invest in upgrading infrastructure to win timely rate approvals from regulators. So while regular rate increases should boost Con Ed's top line, its drive toward clean energy should its lower costs -- a win-win for the company and its shareholders. With management targeting a long-term dividend payout ratio of 60% to 70% of adjusted earnings, and a current yield of 3.8%, Con Ed is an excellent stock for income investors to own for a lifetime.

This underrated dividend stock could make you rich

You may be tempted to dismiss American Water Works (NYSE:AWK) as a boring company and write off its relatively low yield of 1.4%, but the stock's jaw-dropping returns in the past decade should make you sit up and take notice.

AWK Chart

AWK data by YCharts

American Water, which provides water and wastewater services to 15 million customers across 45 states, has paid a dividend for decades and increased it annually for at least the past 10 years. Management has followed a clearly set-out dividend policy that calls for "dividend increases with long-term earnings-per-share growth" and a target payout ratio in the range of 50% to 60% of net income.

That policy suggests investors can expect 7% to 10% growth in American Water's dividends through 2024, in line with its similar target EPS growth, driven by rate increases. It's a regulated utility, so its rates are set and any hikes must be approved by public utility commissions. To ensure it wins timely approvals of those increases when it requests them, American Water is targeting $20 billion to $22 billion in capital investment over the next decade -- such moves go a long way toward convincing regulators. As its rates grow, so should profits and dividends, making American Water a reliable dividend stock to own for decades.