A handful of ordinary people have managed to take the typical retirement age of 63 and cut it nearly in half.
While every early retiree's journey is unique, there is usually at least one common feature of their stories: Each person has the discipline to save a large chunk of their paycheck — often, more than half of it.
Of course, saving is just part of the journey to financial independence. The key to building wealth is to invest that cash and make your money work for you. Still, learning how to squirrel funds away is a crucial start.
Here are five of the best money-saving tips we've learned from early retirees who have put away at least 50 percent of their income.
1.) Track your spending
Steve Adcock and his wife Courtney set aside up to 70 percent of their combined income to retire in their 30s. If you want to bank half your income or more, the Adcocks recommend recording your purchases.
"We know exactly what we bring in and exactly what we spend — and on what," says Adcock. "Knowing where our money goes is critical to maximizing our savings and pinpointing where we could probably cut back."
They prefer using an Excel spreadsheet, but sites like Personal Capital, Mint and You Need a Budget will keep track of your purchases for you.
2.) Start with the small changes
According to Chris Reining, who built a $1 million portfolio by age 35 and retired two years later, the key to saving big is to start small.
"I know there are some people out there that say you shouldn't worry about the $5 latte, but the more I think about it, cutting out the $5 latte was a good place to start," says Reining. "Because if you try to downsize your house, get rid of all yours cars and make all of these drastic changes, it's so overwhelming and you're not going to do any of it."
Ultimately, he says, "the small changes will lead you to be able to make the big changes."
3.) Focus on cutting the big 3
Keep the "big three expenses" — housing, transportation and food — as low as possible, says early retiree Justin McCurry. "Look at those top expenses and see if there's any negotiating room." Doing that helped him and his wife save up to 70 percent of their income and build a $1 million portfolio in a decade.
They stayed in the starter home they bought out of grad school and paid off their mortgage in 2015, meaning that, on a monthly basis, they only cover utilities and maintenance.
In terms of transportation, "we kept the cars that we bought brand-new in college for 16 years and just replaced them last year," says McCurry. And they only budget $500 a month for groceries.
4.) Pack your lunch
Scott Alan Turner paid off more than $70,000 in loans and became a millionaire by 35. His No. 1 savings tip is simple: Pack your lunch every day. After all, dining out can add up to hundreds or even thousands of dollars a month if you're not careful.
In the 10 years Turner spent working a corporate job, he only bought lunch out a handful of times. Instead, he cooked large batches of food on Sunday to eat throughout the week.
5.) Figure out what you actually need and cut out everything else
This Colorado-based couple saved $1 million in four years so they could retire by age 43. They did it by spending only what they needed to spend and saving the rest — no exceptions.
If you figure out what really makes you happy and don't waste money on things that aren't important to you, you too could curb your spending and leave the working world whenever you're ready.