The Washington Utilities and Transportation Commission's consumer protection staff has recommended about $15.6 million in penalties against CenturyLink, one of the largest amounts ever recommended by commission staff. 

The commission will host a prehearing conference on the case on April 30. 

The proposed fines stem from an investigation spurred by what commission staff characterizes as a "substantial increase" in customer complaints against CenturyLink, which is the largest local telephone company in Washington state with about 650,000 business and residential lines statewide. 

In its investigation, commission staff reported over 1.66 million violations involving service quality, service interruptions, and outages from spring of 2023 to earlier this year. 

State law allows the commission to levy fines of up to $1,000 for each offense committed by public service companies.