It’s not that people fail at saving because they don’t understand money. Just about everyone can explain a savings account. Almost everyone understands that you have to spend less than you earn. And compound interest can be explained to a very patient child. But people don’t save their money. Something happens between the plan and the outcome, and most people quietly decide it means that they are bad with money, that they are weak-willed, that they are not trying hard enough.

None of that is quite right. What's actually happening is that your brain is running a specific calculation – and getting it consistently, measurably wrong.

The Calculator That's Broken by Design

Economists have given this the name “hyperbolic discounting” – it sounds like something a sixth-form physics teacher would invent to torment you. But the idea underneath it is genuinely fascinating. Your brain doesn’t treat money in the future as being worth the same as money in the present. That much you’d expect. And this is all perfectly rational: a pound today is worth slightly more than a pound next year – because of inflation, interest rates, basic logic. It’s accounted for by financial models, and it’s called the time value of money.

The calculation our brains use for choices between something now and something later is not rational — researchers have found that the brain applies a discount rate to the future reward that is completely out of proportion to anything happening in the real economy. A classic experiment had most people preferring £50 today over £100 in a year's time. Waiting would have effectively doubled their money – an annual return that no savings account on the planet comes close to offering.

Your brain, in other words, is quietly treating next year's £100 as if it were worth roughly £40 in today's terms. It isn't. But that's the sum being run.

The Moment It Kicks In Hardest

Here's the particularly awkward part of this distortion: it doesn't stay constant. It gets dramatically worse the closer “now” gets.

When you ask someone in January whether they’d like to save £200 in March or spend it in March, they’re very sensible about it. The concept of March in the future feels responsible. So they save it. But when March arrives as a Tuesday afternoon and there’s a perfectly good reason to spend £200, the calculation shifts almost completely. The future reward of having savings, of feeling secure, of being the version of yourself who’s sorted – this all suddenly feels very faint and far away. Meanwhile the present reward is right there, solid and real with a price tag on it.

So people who genuinely intend to save often just don’t. It’s not a character flaw. There’s just a timing problem. At the moment of decision – the checkout, the sale, the impulse – your brain’s discounting is at its most aggressive, and the future version of you who wanted the money saved is at its least vivid.

What It Feels Like From the Inside

Run faulty arithmetic and your reasoning looks sensible. Feel the here and now but can only very vaguely sense the future. But our brain reads our vague sensing of the future moment as evidence that it matters a bit less. And not in some dramatic or spendthrift sense. Just a bit. Slightly. Just enough.

This is the basis of saving advice: ‘transfer the money before you can spend it’. It’s very effective and, in a way, a bit annoying. The reason for this is that the advice isn’t about saving: it’s about taking the moment of decision and removing it. Automatic standing orders, salary sacrifice pension schemes and apps which round up your transactions and transfer the difference all work on the same principle: the saving happens before you’ve got to Tuesday afternoon and the broken calculator never gets switched on.

Recognising that your brain discounts the future by something closer to 50% than 5% doesn't fix the problem on its own. But it does make the failure make sense, which is more useful than blaming yourself. You're not bad at saving. You're just expecting your brain to do maths it was never built to do.

FAQ

What is hyperbolic discounting?

Hyperbolic discounting is the tendency for the human brain to give far greater value to money now than to money later on. The amount by which it does so exceeds what inflation and interest rates justify, and so explains why people who understand saving find it so hard to save in fact.

Why do people choose £50 today over £100 in a year?

Because the brain discounts future rewards much more than real economic conditions justify. A classic study found that most people chose to receive £50 today rather than £100 in one year’s time. The brain in effect calculates that £100 due in a year’s time will have the same value as about £40 today.

Why is it easier to plan to save than to actually save?

At the point of spending in March the present rewards are perceived to be strong and the future benefits of saving weak. The perception of saving £200 for March changes over time and is a function of timing rather than a character flaw.

How can I save money if my brain undervalues the future?

Removing the moment of decision by saving automatically before you can spend money is a better approach to managing your savings than knowing about the bias and hoping for the best. Set up a standing order, join a salary sacrifice pension scheme or use an app that helps you save by rounding up your purchases and transferring the difference to your savings account.