Retail deposit mix is the composition of a bank's deposits from individuals and small businesses, broken down by product: non-interest-bearing current accounts, instant-access savings, notice accounts and fixed-term deposits. It is usually also analysed by whether balances are covered by deposit insurance and by how long the customer relationship has lasted. Treasury teams track the mix because each type of retail deposit has a different cost and a different tendency to leave.
A mix weighted towards demand deposits is cheap but can be withdrawn at once; a mix weighted towards a term deposit base is more predictable but costs more. When interest rates rise, customers tend to move from current accounts into higher-paying products, which raises funding costs and the bank's deposit beta. The mix also drives the deposit runoff rate assumptions used in the liquidity coverage ratio.