Lesson 5 of 7
When you invest, your capital is at risk.
We're available whenever the markets are open, from Sunday night through to Friday night.
If you have money set aside to invest but you also carry debt, you face a decision that comes before any other investing question. Interest on that debt is already working against you, and each month it can reduce what you have available for other goals.
If your priority is how to get out of debt, understanding the true cost of what you owe is a practical first step. This article explains how to compare debt interest against potential investment returns, and how to decide where each pound is likely to do the most work.
Debt charges you interest. Investments offer uncertain returns. When the interest rate on your debt is higher than the return you might realistically earn, paying down the debt can be a more effective use of spare money than investing.
This is not about avoiding investing. It is about recognising that high-cost borrowing creates a headwind. The debt grows by a fixed, known rate. An investment can rise, fall or stay flat, and you may get back less than you put in.
Debt readiness is part of investing readiness. Bringing high-cost borrowing under control can reduce pressure on your monthly budget and make it easier to stick to a long-term plan.
Debt is money you owe to a lender. It could be a credit card balance, an overdraft, a personal loan, car finance, a student loan or a mortgage.
Each debt comes with an interest rate. This is the percentage charge applied over time for borrowing. You repay the debt through payments that usually cover some of what you borrowed (the balance) plus interest.
Not all debt is equally expensive. High-cost debt is typically unsecured borrowing where rates can be high and balances can be slow to reduce if you only make minimum payments. Common examples include credit cards, overdrafts, payday loans and some store cards.
Lower-cost, structured debt can work differently. Mortgages and student loans, for example, often have structured repayment rules and can be more predictable within a budget. This matters because not all debt blocks investing in the same way.
Affordability is the other checkpoint. If you cannot meet minimum repayments, or if a sudden expense would force you to borrow again, that is usually a sign to focus on stability first. Building an emergency buffer can help reduce the risk of taking on more debt. As shown in the graph below, the interest rate on your debt can help you decide what steps to take.
Interest rate is the deciding number. Compare what each debt costs you against what an investment might return. If the debt rate is higher, paying it down often has the stronger impact.
Guaranteed savings beat uncertain gains. Paying off debt saves interest you would otherwise pay. Investment returns are uncertain, and you can lose money.
Affordability comes first. Before you invest, confirm you can meet repayments and maintain a small emergency buffer.
Priorities have an order. High-cost debt is usually addressed before investing, while lower-cost, structured debt may be managed alongside longer-term investing once it is affordable.
Managing debt is ongoing. Even after you start investing, the same interest-versus-return comparison can help you decide what to do with spare money when circumstances change.
Suppose you have £1,000 available and two choices.
Choice one: Pay down a credit card balance charging 22% annual interest. If you clear £1,000 of that balance, you avoid paying about £220 in interest over the next year. That saving is certain.
Choice two: Invest the £1,000. The value of investments can go up or down, and returns are not guaranteed. Your capital is at risk.
In this situation, the certain interest saving from paying down the high-cost debt is likely to be more valuable than taking investment risk for an uncertain outcome.
Now change the picture. If your only debt is lower-cost and repayments are affordable, and you have an emergency buffer in place, you might decide to invest while continuing regular repayments. The key difference is that the interest cost is smaller and your budget can tolerate market ups and downs.
List every debt and its interest rate. Include credit cards, overdrafts, personal loans, car finance, student loans and any mortgage. Use statements or online accounts to find the rates.
Sort them by cost and urgency. Separate high-cost borrowing (often revolving credit like cards and overdrafts) from lower-cost, structured borrowing.
Check affordability and your emergency buffer. If you are relying on credit to cover essentials or would need to borrow again after a surprise bill, consider building a cash buffer before committing money to markets.
Decide where the next pound goes. If you are working out how to get out of debt, a practical approach is to direct spare money towards the highest-cost balances first while keeping up minimum payments on the rest.
Review regularly. This is a repeatable way of managing debt. Changes to income, expenses or borrowing costs can change the result, so revisit the list when something shifts.
If your debt feels unmanageable, free help on debt is available in the UK. Free services can help you understand your options and set out a realistic repayment plan.
Investing spare money while carrying high-interest debt: High-cost borrowing can outweigh what you might gain from investing, especially over shorter timeframes.
Ignoring the interest rate and treating all debt as the same problem: A lower-cost structured debt and a high-cost revolving balance often deserve different priorities.
Skipping the emergency buffer: Without a buffer, unexpected expenses can push you back into borrowing and undo repayment progress.
Chasing investment returns to try to outrun debt interest: Markets do not move on demand, and returns can be negative.
Check the interest rate on every debt before you decide where spare money goes.
High-cost debt often takes priority over investing because the interest saving is certain.
Low-cost, structured debt can sit alongside investing once repayments are affordable.
Build a small emergency buffer before committing money to markets.
Free UK debt help exists, and using it is a practical step when you need support.
It depends on the interest rate and whether repayments are affordable. If you carry high-cost debt, such as credit cards or overdrafts, clearing it first often makes sense because the interest you avoid is certain while investment returns are uncertain. If your only debt is lower-cost and affordable, you may decide to invest alongside repayments.
Start by prioritising the most expensive debt while keeping up minimum payments on everything else. Keep a small emergency buffer so you are less likely to borrow again when something unexpected happens. As high-cost balances reduce, you can choose how to split spare money between continued repayment, savings and investing.
Free UK debt advice is available through charities and government-backed services. They can help you understand options, set a budget and work out a realistic repayment plan. If you are struggling to keep up with payments, getting support early can be useful.
It can be, as long as repayments are affordable and you have an emergency buffer. Investing involves risk and returns are not guaranteed, so the decision depends on how stable your budget is and how you would cope if markets fall in the short term.
