Glossary
Share of wallet
The percentage of a customer's total spending in a category that goes to one company rather than its competitors.
Share of wallet measures how much of a given customer's total spending in a product or service category a company captures, as opposed to how much goes to competitors. A retail bank customer, for example, might hold a mortgage, savings account and credit card, and a bank captures only a portion of that customer's total financial-product spending if some products sit elsewhere.
This differs from market share, which compares a company's revenue against the whole market across all customers, while share of wallet is calculated per customer or segment and requires estimating that customer's total category spend, often through surveys or third-party data, since a company rarely sees what a customer spends with competitors directly.
Share of wallet is used to find expansion opportunity within an existing customer base, which is usually cheaper to grow than acquiring new customers, and it is a common input to customer lifetime value and RFM analysis-based segmentation. The main pitfall is treating estimated wallet size as precise; because it relies on self-reported or modeled totals, small errors in the denominator can make share-of-wallet trends look more meaningful than the underlying data supports.
Last reviewed September 22, 2026