Car loan, £11,400 left, 4.1% fixed, four years remaining. I have £300 a month spare beyond my regular investing. Emergency fund is full at six months. Mathematically I know the expected return argument, but 4.1% guaranteed isn't nothing and I hate the payment existing. Is there a framework for this beyond 'compare the rate to expected returns'?
Split it if you can't decide. £150 extra at the loan, £150 invested. You'll clear the loan roughly two years early and still keep investing. Nobody looks back at a 50/50 split and regrets it, whereas both pure options have a version where you feel dumb.
This is what I did with a similar rate. Also check for early repayment penalties before you overpay — some loans charge and it changes the maths.
One thing to verify: is 4.1% the APR or the flat rate? On some car finance the advertised rate is calculated on the original balance rather than the reducing one, which makes the effective rate close to double. If that's the case, pay it off and stop reading.
Checked and it's APR on a reducing balance, so 4.1% is the real number. Good thing to flag though.
Six month emergency fund plus regular investing plus £300 spare means you're doing fine either way. This is a good problem and the difference between the two paths over four years is small enough that peace of mind should win.
Slight dissent on the guaranteed-return framing: paying down a loan gives you a guaranteed 4.1% only in the sense of avoided interest, and that money is then locked in a depreciating car rather than in something liquid. That's worth weighing if your emergency fund is your only accessible cash.
@overlap_owen · 6mo ago · 3 replies
The framework I'd use is: what does the debt do to your flexibility, not just to your arithmetic.
A £300/month payment is a fixed claim on your income for four years. If you lose your job, the investment portfolio is optional and the loan isn't. Paying it off is buying certainty and reduced monthly obligations, which is a real product even though it doesn't show up in a spreadsheet return.
That said, 4.1% is genuinely low. If it were 9% this wouldn't be a question. At 4.1% with a full emergency fund, this is close enough to a coin flip that I'd let the tiebreaker be how much you dislike the payment — and you've already said you hate it. That's a legitimate input.
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@overlap_owen · 6mo ago
It's not soft at all. Reducing your required monthly outgoings raises the floor under every other decision you make for the next four years.
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@sinking_funds_su · 6mo ago
The 'fixed claim on income' framing is what I was missing. Makes the certainty side feel less like a soft factor.
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