There are two kinds of people: those who stick to the rules and those who believe rules are meant to be broken. If you’re in the first camp, this list might make you a little uneasy. Personal finance is packed with so-called “rules of thumb.” Some can be useful, but others can backfire — especially if they don’t fit your unique circumstances in retirement.
Here are six personal finance rules you should probably break for a better and more secure retirement.
1. Buy Low, Sell High
Conventional wisdom dictates that when it comes to stocks, you should buy low and sell high. However, this method is actually high-risk and typically leads to less-than-desirable returns. Stocks that are selling low are often in trouble as a result of deteriorating fundamentals or shrinking market share. When mutual fund managers recognize these issues, they sell (which effectively drives the price of the stock down). In other words, trying to buy low and sell high these days usually means you’re buying stocks that are on their way out.
A better rule of thumb is to buy high and sell higher.
Many smart traders look for stocks that are near their yearly highs in strong industries. These stocks are typically trending upward, and the stock has proved its value before you buy it. The potential for more growth is consistently better than fishing for bottom-feeder stocks.
2. Subtract Your Age From 100 to Determine How Much of Your Portfolio Should Be in Stocks
Financial advisors often recommend that when it comes to retirement savings, the younger you are, the more money you should put in stocks. This is because the older you are, the less time you have to recover from any downturns in the stock market. So as you approach and enter retirement, you should convert more of your volatile growth-oriented investments into fixed-income securities, such as bonds.
The traditional rule of thumb has been to subtract your age from 100. The difference represents the percentage of stocks you should keep in your portfolio. For example, at age 40, 60% of your portfolio should be in stocks, and by age 70, only 30% of your portfolio would consist of stocks.
But today, Americans are living longer, so some may consider that rule to be out of date. Financial planners now recommend that the rule should subtract your age from the numbers 110 or 120. Because you may need to make your money last longer, you’ll need the extra growth that stocks can provide.
Keep in mind that your exact allocation is dependent on many different factors not covered by this rule of thumb. You should consider wealth, time horizon, retirement date, inflation, risk tolerance, financial goals, and so much more.
3. Pay Off All Debt Before Retirement
It’s wise to enter retirement with as little debt as possible. The fewer monthly payments you carry, the more freedom you’ll have to cover essentials — like healthcare — and enjoy the extras, like travel or hobbies.
That said, not all debt is created equal. While paying off high-interest debt such as credit cards, personal loans, or car loans should be a top priority, the decision about your mortgage is more nuanced.
Many people dream of a mortgage-free retirement, but if your mortgage rate is relatively low, it may be smarter to direct extra cash into retirement savings instead. Money invested in a diversified portfolio has the potential to grow faster than the interest you’re paying on your home loan.
There can also be tax advantages. For example, higher-income households who itemize deductions may benefit from the mortgage interest deduction, which lowers taxable income. In some cases, the combined effect of investment growth and tax savings makes keeping a mortgage more efficient than rushing to pay it off.
Bottom line: Focus first on eliminating high-cost debt. Then weigh the pros and cons of paying down your mortgage versus investing more for retirement. The right choice depends on your interest rate, tax situation, and comfort level with carrying debt.
Review some more pros and cons of retaining a mortgage into retirement.
4. Replace 80% of Your Income for Retirement
How much income will you need in retirement? Many personal finance experts suggest that you should aim to replace 80% of your pre-retirement paycheck. That means if your pre-retirement salary is $100,000 a year, you’ll need to make $80,000 annually from Social Security, pensions, portfolio withdrawals, and other sources of income.
While this advice is well-intentioned, it is not one-size-fits-all. Many people actually need less income to maintain their standard of living in retirement because they’re no longer contributing to retirement plans, paying Social Security taxes, and paying Medicare taxes. Others spend more when they first retire, and then their spending tapers off. Your actual needs can vary considerably.
To get a better idea of the income you’ll need in retirement, you should look at your expenses (rather than your current income). Will your mortgage and other debts be paid off? Do you plan on spending a lot on retirement? Do you have children who could be financially dependent on you in retirement? Do you plan on cooking at home less and dining out more? How about medical costs?
Of course, we can’t predict the future. But rather than looking at 80% as a hard and fast rule, it may be a better idea to come up with a customized figure based on planned and potential expenses. Once you have a good estimate of your retirement spending needs, you can compare that to a sustainable level of portfolio withdrawals and other retirement income to see if your savings are on track.
5. The 4% Rule
Those who tend to favor simplicity over a customized retirement plan often refer to the 4% rule. This rule dictates that if you withdraw 4% per year from a diversified portfolio of stocks and bonds – adjusted annually for inflation – then you’ll have enough to last for 30 years in retirement (based on historical returns). For example, if you want $100,000 per year in retirement (not counting Social Security or pensions), you’ll simply divide $100,000 by 4% to get a target retirement savings of $2,500,000.
The problem with this rule is that the 4 percent rule was a product of the 1990s, a time when interest rates were significantly higher. In fact, the man who invented the 4% rule, William Bengen, now recommends the 4.7% rule.
No withdrawal rate can ensure you won’t run out of money in retirement or, conversely, withdraw so little that you end up with more savings than you’ll need late in life. A better idea is to start with a reasonable withdrawal rate that has a decent chance of making your money last, then making adjustments along the way based on investment performance. You may also explore using a bucket strategy.
6. Always Max Out Your 401(k)
Conventional advice says to put every spare dollar into your 401(k). While tax-deferred savings are powerful, this isn’t always the smartest move.
It can be a better idea to prioritize capturing your employer match, then balance retirement contributions with other accounts that give you flexibility and control. This is especially true if:
- Your plan has limited investment options or high fees, you might be better off directing some savings to an IRA or taxable brokerage account.
- Having accessible funds outside of retirement accounts will help you bridge early retirement years, pay for healthcare, or seize opportunities without penalty.
Learn more about the savings playbook, a common sense approach for knowing how much to save and where.
The One Rule You Should Follow
When it comes to your future, you can’t afford to make too many bad moves, but that doesn’t mean you always need to play by the same rules as everyone else.
You should definitely focus on retirement planning that takes your individual needs and circumstances into account and continue to adjust that plan as circumstances dictate.
About Boldin
The Boldin Planner is powerful software that puts you in control. It’s almost like having a financial expert at your fingertips. Research shows that people with a written financial plan do 2.7 times better financially. They’re also 54% more likely to live comfortably in retirement. That’s not luck, that’s taking control of your money. The Boldin Planner has been named the Best Financial Planning Software of 2025, and the company was selected as a Top Innovator in UpLink’s Prospering in Longevity Challenge and named to the FinTech 100 by CBInsights.
And, doing it yourself doesn’t mean doing it alone. Beyond the Boldin Planner, we offer classes, coaching, and expert guidance from CFP® professionals through Boldin Advisors.