Prismm, a FinTech company providing inheritance infrastructure for banks and credit unions, has launched its Deposit Mortality Index (DMI), a new measurement tool designed to help financial institutions identify future deposit risks linked to ageing account holders and wealth transfers.
The index estimates that $1.5tn in deposits could leave US financial institutions over the next decade as account holders pass away. Prismm said the DMI has scored all 8,429 federally insured US banks and credit unions, providing institutions with a benchmark for understanding the future resilience of their deposit portfolios.
Created by Prismm founder and CEO Martha Sylla Underwood, the index uses publicly available data sources including FDIC branch deposit figures, Census demographic information, Federal Reserve holdings data and Social Security Administration life tables to assess potential deposit outflows and retention opportunities.
Unlike traditional deposit reporting methods that primarily examine balances and historical trends, the DMI evaluates how deposit portfolios may perform as account ownership changes over time. Prismm said the tool is designed to help executives identify maturity risks within their customer bases and take action before assets leave the institution.
The launch comes as significant wealth transfers are expected to reshape the financial services landscape. Prismm said an estimated $124tn in US household wealth will change hands by 2048, with around 70% of inherited balances leaving the original financial institution.
Each DMI report provides institutions with a composite score, national tier and ranking compared with other scored organisations. The analysis also highlights demographic, growth and portfolio factors influencing deposit outlooks, alongside areas where institutions may be able to improve retention strategies.
Prismm said the index was calibrated once against the full national distribution of institutions and then frozen to ensure scores remain comparable over time. Financial institutions can request access to the methodology, assumptions register and change log, while individual reports are available for $799.
Prismm provides inheritance infrastructure for banks, credit unions and wealth management firms. Its platform integrates with existing financial systems to support the organisation, preparation and transfer of assets during major life transitions, helping institutions maintain customer relationships and improve continuity across generations.
Prismm founder and CEO Martha Sylla Underwood said, “Banks and credit unions have never had a way to measure the future health of their deposits until now. The Deposit Mortality Index gives executives a completely new perspective by revealing risks and opportunities that traditional reporting simply cannot see. As wealth changes hands over the coming decades, institutions that understand the maturity of their deposits will be far better positioned to preserve deposits and retain relationships for generations to come.”
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