Should you pay off debt or save money? How to decide

When you have spare money and both debt and an empty savings account staring at you, the decision about where to put it can feel paralysing. Both choices feel right in different ways. Paying off debt feels responsible. Saving money feels prudent. The way to make a clear decision is to look at the interest rates involved and work through a simple logic flow.

Compare the interest rate on your debt with the interest rate on savings

The core of the decision is mathematical. If your debt is costing you 20 percent in interest and the best savings account you can access is paying 5 percent, every pound you put into savings earns you 5 percent while costing you 20 percent in unpaid debt. You are 15 percent worse off for every pound saved rather than used to pay down that debt. In almost all cases, high-interest debt should be cleared before building savings beyond a minimal emergency buffer.

The calculation shifts when debt interest is low. A mortgage at 4.5 percent and a savings account at 5 percent means you are actually better off saving than overpaying the mortgage. Personal loans and 0 percent credit card deals also change the picture significantly.

Always maintain a minimal emergency buffer regardless

Even if you have high-interest debt, putting every available pound toward it with zero savings is risky. If something goes wrong, a car repair, an appliance breaking, a period of reduced income, you will likely need to add more to the debt to cover it. A small emergency fund of around £500 to £1,000 sitting in an easy-access account provides enough cushion to handle most small emergencies without touching the credit card again. Build this first, then focus on the debt.

Employer pension contributions are a special case

One situation where saving takes precedence over debt repayment almost universally is when your employer offers pension matching. If your employer will match your pension contributions up to a certain percentage, not contributing at least enough to get the full match is leaving free money on the table. Even if you have debt, getting the full employer match first and then directing remaining money to debt repayment is usually the right priority order.

The psychological case for saving something

Pure financial logic says pay off expensive debt first. But financial decisions are not made in a pure logic environment. Many people find that saving nothing and focusing entirely on debt feels demoralising and unsustainable. Splitting spare money, perhaps 80 percent toward debt and 20 percent into savings, produces slightly worse financial outcomes by the numbers but may produce much better outcomes in practice if it keeps you motivated and consistent. The plan you stick to beats the optimal plan you abandon.