Mental accounting
The habit of sorting money into separate mental accounts by source or purpose, such as rent money, holiday money or ‘found’ money, and treating each by its own rules. Money is interchangeable in fact but not in how people spend it.
What drives it
Labelled pots make budgeting easier and limit spending without constant calculation. For identification it explains carrying a credit card balance while holding savings, spending a tax refund in a weekend, or treating winnings as ‘house money’.
How it shows
Work
A bonus spent in three days because it ‘wasn’t really salary’, using the whole training budget because the money is ‘there to be spent’, treating company money as less real than one’s own.
Relationships
Separate pots that partners guard: ‘my money’ and ‘our money’ with different rules, a gift from parents that can’t be touched, arguments when one partner moves money between pots.
Self
Notice which money feels easier to spend, such as cash from a sale, a refund or birthday money, and whether you keep savings while paying interest on a card.
What tells it apart
Emotional spending: Emotional spending is driven by mood. Mental accounting is driven by labels, and a windfall may be spent freely in a calm mood because it sits in the ‘fun’ account.
Loss aversion: Loss aversion weighs losses more than gains. Mental accounting decides which account a loss or gain is booked to, which can change how big it feels.
Money scripts (Klontz): Money scripts are beliefs about what money means. Mental accounting is a bookkeeping habit that runs alongside any set of beliefs.
A test
Ask whether the person would spend a £200 refund the same way as £200 from their salary. A clear difference in how freely each is spent points more likely to mental accounting.
Questions to carry
- Where did the money spent this week come from, and would it have gone the same way if it came from the salary?
- Which pot of my money do I treat as not quite real?
How strong the research is
moderate. Field data support the core claim that people don’t treat money as interchangeable: Hastings and Shapiro (2013) found that when petrol prices rose, households switched to cheaper grades of fuel more than the change in their income could explain. Mental accounting is an umbrella for several effects rather than one tested model, and many of its classic demonstrations rest on hypothetical choices.
Where it comes from
Richard Thaler, 1985 (Mental accounting and consumer choice, Marketing Science). Thaler, 1999 (Mental accounting matters)