Seven retirement rules of thumb to check your savings progress

You do not need a massive spreadsheet to figure out if you are on track for retirement. While detailed projections are eventually necessary, basic mental shortcuts can give you a surprisingly clear picture of where you stand. These seven rules of thumb offer a fast way to estimate your savings targets, asset mix, and withdrawal limits without getting stuck in the math.

1. The 4% Rule (Safe Withdrawal Rate)

Financial planner William Bengen introduced this standard benchmark in 1994 to help retirees avoid outliving their money. After reviewing decades of historical market data, he found a sweet spot. If you withdraw 4% of your portfolio’s value during your first year of retirement, then adjust that exact dollar amount for inflation every year after, your money has a high probability of lasting 30 years.

Say you retire with a $1,000,000 portfolio. Your first-year withdrawal is $40,000. If inflation runs at 2.5% that year, your second-year withdrawal bumps up to $41,000.

This rule assumes your money is invested in roughly 50% to 75% US stocks (shares of ownership in companies) and the rest in bonds (loans you make to companies or governments that pay fixed interest). If you plan to retire early and need your savings to last 40 or 50 years, you will want a slightly lower initial withdrawal rate. Aiming for 3.3% to 3.5% provides a wider margin of safety.

2. The 25x Rule (Target Nest Egg)

This is simply the math of the 4% rule running in reverse. It tells you exactly how much money you need to save to support the lifestyle you want. Find your target nest egg by estimating the annual income you need to pull from your investments, then multiply that number by 25.

If you figure you need $60,000 a year from your portfolio to cover your living expenses, multiply $60,000 × 25. Your target nest egg is $1,500,000. Because it is the inverse of the 4% rule, this shortcut relies on the exact same 30-year timeline and inflation adjustments.

3. The 80% Income Replacement Rule

How do you know what your future annual expenses will be in the first place? A good baseline is the 80% rule. It assumes you will need roughly 80% of your pre-retirement gross income to maintain your current standard of living after you stop working.

You rarely need to replace 100% of your paycheck. Once you retire, several major expenses vanish. You stop paying payroll taxes like FICA, your daily commuting costs drop, and you are no longer funneling 10% to 15% of your income into retirement accounts. If you earn $100,000 a year right before retiring, plan to need roughly $80,000 a year from all income sources combined. That total includes your investment withdrawals, Social Security, and any pensions.

4. The Rule of 72 (Doubling Time)

The Rule of 72 is a mental shortcut to estimate how long it takes for an investment balance to double at a fixed annual rate of return. Just divide 72 by your expected percentage return.

A 7% return is a standard baseline assumption for a diversified stock portfolio before factoring in inflation. Divide 72 ÷ 7, and the result is about 10.3. Thanks to compound interest—where your interest earns its own interest—your money will double every 10.3 years, even if you never deposit another dime.

5. The 15% Savings Rule

Financial planners generally recommend saving 15% of your gross income for retirement, provided you start in your twenties. The good news is that this 15% target includes any employer match. If your company matches 5% of your contributions, you only need to save 10% of your own paycheck to hit the mark.

This rule relies heavily on starting early. Doing so allows decades of compound growth to do most of the heavy lifting. If you begin saving later in life, you have to adjust the rule upward. Someone starting from zero at age 40 will likely need to set aside 20% to 25% of their income to catch up to their 25x target nest egg.

6. The Rule of 110 (Asset Allocation)

As you get closer to retirement, your capacity for risk decreases. A severe market crash the year before you retire is far more damaging to your plans than one that happens when you are 30. The Rule of 110 helps you calculate your asset allocation—the specific mix of stocks versus safer, less volatile assets like bonds in your portfolio.

Subtract your age from 110. The resulting number is the percentage of your portfolio that belongs in stocks. If you are 50 years old, 110 − 50 equals 60. You would keep 60% of your money in stocks and 40% in bonds. Some aggressive investors prefer a “Rule of 120,” but 110 is a solid baseline for a balanced approach.

7. The Rule of 55 (Early Access)

Most people know that pulling money from a traditional 401(k) or IRA before age 59.5 triggers a 10% early withdrawal penalty from the IRS. The Rule of 55 is a lesser-known tax provision that serves as a massive loophole for early retirees.

If you leave your job—whether you are laid off, fired, or quit—during or after the calendar year you turn 55, you can pull money from that specific employer’s 401(k) without paying the 10% penalty. You still owe regular income tax on the withdrawals. Also, the rule applies exclusively to the 401(k) associated with the job you just left. You cannot use it to empty out your previous accounts or IRAs early.

Turning rules into numbers

These rules are excellent starting points, but they mostly rely on nominal dollars—the literal numbers you will see printed on a future bank statement. For accurate long-term planning, you have to look at real dollars. Real dollars adjust your future balance for inflation to show what your money will actually buy. If inflation averages 2.5% a year, $1 today will only have the purchasing power of $0.42 in 35 years.

To run your own exact numbers, adjust for inflation, and see a month-by-month schedule of your growth and safe withdrawal limits, use our Retirement Calculator.