Good debt vs. bad debt: Why what you've been told is probably wrong

• Personal finance advice typically divides debt into two categories, with "good debt" including college loans, loans for buying a home and business loans.
• It's more complicated. The ability to turn a bachelor's degree into an income that outweighs the loans, and finance the purchase of a house with a mortgage you can afford and a value that increases beyond the sale price, are no guarantees in the U.S. today. 

As inflation continues to surge, hitting 8.5% in the U.S. in March, it's important find ways to protect your savings.

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You may have heard of debt being categorized as two types: good debt and bad debt. "Good" debt is defined as money owed for things that can help build wealth or increase income over time, such as student loans, mortgages or a business loan. "Bad" debt refers to things like credit cards or other consumer debt that do little to improve your financial outcome. These are oversimplifications. The distinctions between "good" and "bad" debt are a lot more nuanced.

It's worth revisiting this topic and understanding the new rules of the debt game. While student loans and mortgages can be used successfully to build wealth or increase your income, that isn't always — or necessarily — the case. Using "good" debt successfully depends on a number of factors.

Student loans

Debt is a necessity for many lower- to middle-income Americans who wish to fund a college education, but as we've all come to understand, not all degree programs are created equal. According to Carrie Schwab-Pomerantz, a financial advisor, board chair and president of the Charles Schwab Foundation, the rule of thumb is that you shouldn't borrow more (in total) than you expect to earn in your first year on the job.

For example, if you're pursuing a master's in education and the average starting salary for someone from your school with that credential is $65,000, then you shouldn't take out more than $65,000 in loans to fund that degree.

This guideline is premised on the notion that with yearly salary increases, you should be able to keep up with the interest in your debt and pay it off within the standard 10-year repayment window. That said, if you're graduating into a shaky economy or otherwise unstable job market, you may wish to have even less debt.

Of course, it's not possible to anticipate a recession years in advance, so matriculating freshmen can't reasonably know their job prospects at expected time of graduation. Still, if you're in school now, the situation suggests minimizing your debt even more than usual. Or if you're considering going back to school, avoid as much debt as possible. Some lingering effects of the Covid-19 recession may still be present at graduation.

Mortgages

Mortgage debt historically has been considered one of the safest forms of good debt, since your monthly payments eventually build equity in your home. However, as the Great Recession and subprime mortgage crisis taught us, prices don't always rise indefinitely, and borrowing more than you can afford — or using mortgage terms you don't fully understand, such as adjustable rate mortgages, also known as ARMs — can pose a significant risk. During the subprime mortgage crisis, millions of borrowers lost their homes to foreclosure as home prices dropped and ARM loan payments adjusted upward.

Mortgages still remain one of the most accessible ways for millions of Americans to build a relatively safe investment in the form of home equity, but it requires an understanding of how much one can borrow, as well as a solid grasp of the home market at the time you buy.

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Generally speaking, your monthly mortgage payment (including any PMI — private mortgage insurance) should be less than 28% of your gross monthly income. You should also consider other factors, such as the terms of your loan. While ARMs offer lower interest rates (and thus monthly payments) in the beginning, they can adjust upward over time, resulting in higher payments that you may not fully anticipate if you don't read the fine print.

Find a mortgage payment level that works for your household long term, factoring in the possibility of layoffs, a larger family or any other number of events that can affect your available income in the future.

The No. 1 debt question

Whether it's borrowing for a degree, home, car or new business, the final determinant of whether the debt you're amassing is good is this question: Will this debt pay me back more than what I put in?

It's a question that seems simple but might require a little thought. After you factor in principal repayment, interest payments and the alternative uses of that money, does the debt still make sense? Are you getting all your money back and then some? Could you have done something better with the time and money you're investing?

This thought process will help you determine whether any debt is more burdensome than beneficial, and when you consider it this way, in some cases even credit cards can be more good debt than bad. For example, if you repay all your monthly balances on time and generate significant cash back or rewards, or if you use a 0% APY balance transfer card to repay debt more quickly. 

The key is what the debt does for you — and it should always be more than what you do for the debt.

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