Good Debt, Bad Debt, and the Grey Area in Between

The simple version — and why it doesn't help most people

You've probably heard the rule: a mortgage is good debt, a credit card is bad debt.

That's true as far as it goes. But most people don't sit neatly at either end. They've got a car loan, a personal loan, maybe a few buy now pay later accounts ticking away in the background. The classic examples don't tell you much about where those actually sit.

So let's work through it properly.

What makes debt "good"

Good debt generally does one of two things: it funds an asset that grows in value, or it increases your ability to earn.

A mortgage fits this because property tends to appreciate over time and you're building equity as you pay it down. A student loan fits it (in theory) because higher qualifications can lead to higher income. A business loan fits it if the business generates more than it costs to service the debt.

The other thing good debt tends to have in common: relatively low interest rates. You're not paying a premium just to access the money.

What makes debt "bad"

Bad debt does the opposite. It funds something that loses value quickly — or has no lasting value at all — and usually comes with a high interest rate.

Credit card debt is the clearest example. You're often paying 20–25% interest on purchases that are already spent and gone. Payday loans are worse — the fees can translate to annual interest rates well above 100%.

If the interest costs more than whatever benefit the purchase gave you, it's bad debt.

The grey area — where most people's debt actually lives

Here's where it gets more useful.

Car loans

A car is a depreciating asset. The moment you drive it off the lot, it's worth less than you paid. That technically puts car debt in the "bad" column.

But most people need a car to get to work. If you borrowed a reasonable amount, at a reasonable interest rate, for reliable transport — it's hard to call that bad. It's a necessary expense you chose to finance.

It becomes bad debt when the loan is too large relative to the car's value, the interest rate is high, or you stretched the term out so long you're still paying it off when the car needs replacing.

Personal loans

A personal loan is almost entirely defined by what you use it for.

Use it to consolidate several high-interest debts into one lower-rate loan — that's a smart financial move. Use it to fund a holiday or a wedding — it's hard to call that anything other than bad debt. The loan itself isn't the problem; the purpose is.

Buy now pay later

This one catches a lot of people off guard.

BNPL feels different from debt. There's no interest (usually), no application process, and the amounts feel small. But it is debt — and it stacks up faster than most people realise.

The real danger with BNPL isn't any single purchase. It's having four or five of them running simultaneously, each taking a slice of your income every fortnight. That's money that can't go towards savings or paying off something more important.

If BNPL is replacing spending you couldn't otherwise afford, it's bad debt. If it's genuinely just smoothing out a large one-off purchase you planned for and can repay quickly, it's closer to neutral.

The question to ask about any debt

Rather than trying to classify each debt by type, ask yourself this: is this debt costing me more than it's giving me?

That includes interest, but also the opportunity cost — money tied up in repayments is money that can't go anywhere else.

High-interest debt is almost always worth paying off as fast as you can, regardless of what category it falls into. Lower-interest debt gives you more options.

Knowing which debt to tackle first

Once you've mapped out what you owe — and honestly assessed which debts are working against you — the next step is deciding what order to pay them off in.

That's where a tool like the Debt Payoff Manager is useful. It lets you enter each debt and compare two payoff strategies side by side: the Debt Snowball (smallest balance first) and the Debt Avalanche (highest interest first). You can see exactly how long each approach takes and how much interest you'll save.

Knowing which debt is "bad" is a good first step. Knowing exactly when you'll be free of it is better.

The bottom line

Good debt and bad debt are useful concepts, but the lines blur quickly in real life.

Most debt — car loans, personal loans, BNPL — isn't categorically one or the other. It depends on the interest rate, the purpose, the amount, and whether you have a plan to pay it off.

The clearest signal is usually the interest rate. If it's high, it needs to go. If it's low and it funded something genuinely useful, it can wait its turn.

What matters most isn't which category your debt falls into — it's whether you have a plan to get out of it.