Mental Accounting
Mental accounting is a cognitive bias described by Richard Thaler where individuals categorise money into separate mental 'accounts' based on subjective criteria — such as source, purpose, or emotional significance — and make different financial decisions for money in different accounts even when the actual amounts are fungible.
Mental accounting was formalised by Nobel laureate Richard Thaler as a component of behavioural economics, and it manifests pervasively in Indian investor behaviour in ways that impair optimal financial decision-making. The fundamental irrationality it captures is that ₹1 should be worth exactly ₹1 regardless of whether it came from a salary, a Diwali bonus, a maturity payment, or a win in a contest — yet most people treat these sources very differently.
One of the clearest manifestations in Indian investing is the treatment of 'bonus' or 'windfall' money. Investors who are disciplined about not touching their monthly SIP corpus often treat an end-of-year bonus or tax refund as 'extra' money that can be spent on discretionary purchases or parked in a low-yield savings account rather than deployed into the investment portfolio. The same investor who would never withdraw from their mutual fund to buy a television will freely spend a bonus on one — even though the economic value is identical.
The SIP vs lumpsum psychology is another textbook mental accounting case. Many investors feel that their SIP contributions are 'committed' and psychologically labelled as untouchable long-term investments, while a lumpsum windfall is coded as 'discretionary' and more susceptible to impulsive deployment or spending. This segregation causes suboptimal allocation — the lumpsum might sit in a savings account at 3.5% while the SIP compounds at 12%.
Another Indian-specific manifestation is the separate mental treatment of EPF corpus and voluntary investments. Many investors view their employer PF as guaranteed and 'separate' from their 'real' investment portfolio — leading them to hold excessive equity risk in the voluntary portfolio without accounting for the large, risk-free EPF corpus that already provides a significant fixed income allocation. Proper portfolio construction should view all assets in a single account.
Mental accounting also explains why investors resist realising losses ('the account is not closed until I sell') or are reluctant to use emergency funds already labelled as such even when a genuine emergency arises ('I built this over years and don't want to touch it'). Recognising these patterns is the first step; the corrective is developing a holistic net-worth view that treats all assets as part of a single fungible pool, optimised for total risk-adjusted after-tax return.