Definition
A cost-of-living adjustment, often abbreviated COLA, is an automatic increase applied to an income stream so that its real value keeps pace with rising prices. Without such an adjustment, a fixed payment buys steadily less each year as inflation erodes its purchasing power.
COLAs appear in many settings: government pension programs, union labor contracts, retirement benefits, and some long-term commercial leases. The adjustment is usually tied to a published inflation measure, most commonly the Consumer Price Index, so the increase is rule-based rather than negotiated each period.
Why it matters
How it works
A COLA formula specifies a reference index, a measurement window, and a rule for translating the index change into a percentage raise. For example, a program might compare average CPI in one quarter against the same quarter a year earlier and grant that percentage as the adjustment. Some formulas cap the increase or set a floor of zero so payments never fall. Because COLAs are mechanical, they spread inflation through the economy quickly, which critics note can reinforce a wage-price spiral if inflation is already high.