Butler County filed a $10.9-million lawsuit against 15 phone providers for not billing and collecting 911 assessment charges.

The lawsuit, filed Wednesday in county court, seeks to recover six years of funds. The charges are added to phone bills to help pay for the county’s 911 operations. Data obtained by the county suggests that up to 15 telephone companies may have misrepresented the types and number of phone lines the 911 assessments are applied to, causing “significant” underbilling.

The suit said the misrepresentation results in a lot less funding for the 911 system. The county spent $3.1 million in 2014 to support the system, with $1.7 million coming from 911 fees and $1.4 million coming from tax money.

“Butler County and its taxpayers should not have to subsidize this gap. This is a tax burden on all of our residents and especially impacts our seniors and lower income residents,” said Commissioner Kim Geyer in a statement.