Kill high-interest debt before you invest

Almost everyone who is "bad with money" is just running a guaranteed-loss arbitrage. They are paying 15–22% interest on revolving credit while their investment account targets 6–8% real returns. The bank wins both sides of that trade. Closing it is the highest-return move available to most households — and you do not need a single piece of investment knowledge to do it.

Step 1 — List every debt with its rate. On one page: lender, balance, minimum payment, APR. Sort by APR descending. Be honest about credit cards, store cards, "interest-free" plans whose grace period has expired, BNPL accounts, and any private loans. If you cannot see all of it on one page, you cannot fix it.

Step 2 — Pay minimums on everything, surplus on the top of the list. This is the "avalanche" method. It is the mathematically optimal order — every krona of surplus goes to the highest-rate debt until it is gone, then the next. Yes, the "snowball" method (smallest balance first) feels better psychologically; if you have failed at avalanche twice, switch to snowball — done beats optimal. But avalanche saves more money for the same effort.

Step 3 — Freeze the source. The single most common failure mode is paying off a credit card and immediately re-using it. Take the card out of every digital wallet, remove it from autofill, and either freeze it in the app or physically cut it. Keep one card active for emergencies, with a small limit, on a separate bank.

Step 4 — Refinance what you cannot pay off in 12 months. For debt that will take longer than a year, look at a low-interest consolidation loan or a balance-transfer card with a 0% intro period. Refinancing only works if you also do step 3 — otherwise you have a fresh credit limit on the original card and the new loan on top.

Step 5 — Resume investing the day the high-rate debt is gone. The threshold is roughly the expected long-run return on a diversified portfolio. Anything above ~7% APR: pay first, invest later. Anything below ~4% (typical mortgage): invest in parallel. The 4–7% band is judgment — usually pay first unless you would not start investing at all without the parallel habit.

Common mistakes: • Investing aggressively while carrying a credit-card balance. • Paying off the smallest debt for the psychological win when the largest debt has the highest APR. • Closing the credit account in panic — your credit score takes a hit and you lose the emergency tool. • Treating BNPL ("Klarna pay later") as not-debt. It is debt the moment the grace period passes. • Refinancing without freezing the source — you double the problem.

What success looks like: Every revolving debt at 0 SEK. One credit card with a small limit kept for emergencies, paid in full every month. The monthly amount that used to go to interest now goes straight into the investment account on payday.

Checklist: • Single page list of every debt with APR • Avalanche (or snowball) order chosen and written down • Autopay set for every minimum to avoid late fees • Source frozen for every paid-off account • Day-one investment transfer set up for the month after the last balance hits zero