The Impact of Investment Services on Core Bank Income: Income Contribution Calculator

The Bank Insurance and Securities Association (BISA) commissioned Kehrer Bielan to estimate the impact of an increase in investment services penetration on the use of deposit and lending products. The first stage of this research is summarized in Smart Investment: The Total Return on Investment Services to the Banking Enterprise, available to BISA members.

The Total Impact of Investment Services on Core Bank Income: Income Contriubution Calculator (November 2019)

How do increases in deposit and loan balances attributable to the existence of the investment services business impact the income statement of the institution? The answer to this question is not straightforward because the income from deposit and loan balances fluctuates with interest rate spreads and varies by type of product. Indeed, it also varies for the same generic product across institutions, given each institution’s pricing strategy, and different customer usage rates.

We created a dynamic calculator to help members make a case for the direct impact of investment services on the income of the member’s institution based on the estimates in the study and more detailed deposit and loan pricing for the member’s own institution. The calculator provides estimates of the increase in use of the following products due to the investment services relationship:

  • Checking accounts
  • Savings accounts
  • MMDAs
  • Credit cards
  • First mortgages
  • Second mortgages
  • HELOCs

The member provides information on the member institution’s:

  • Total retail customer households;
  • Share of those households that have an investment relationship with the institution; and
  • The institution’s own estimates of the contribution of each of the 7 banking products to the institution’s income.

The calculator computes the overall impact on the institution’s income due to the additional deposits and loans that investment services clients use.

In addition to using the calculator to demonstrate the value of investment services to the institution, the calculator can also be used to estimate the additional income contribution that would result from an increase in investment services penetration.

The Income Contribution Calculator is available to BISA members. To learn more about becoming a member of BISA and obtaining the report, contact


The Bank Insurance & Securities Association is the leading financial services industry association dedicated to serving those responsible for the marketing, sales and distribution of securities, insurance, and other financial products and advisory services through the bank channel. Member companies include depository institutions of all sizes, their broker/dealer and mutual fund subsidiaries, third-party marketing companies, product manufacturers and firms providing products, technology or services to support these enterprises. For more information, visit