Newsletter platform Substack has raised $100 million in Series C financing led by BOND and The Chernin Group, with participation from existing backer Andreessen Horowitz and individual investors Rich Paul and Jens Grede. The round lifts the San Francisco-based company’s valuation to about $1.1 billion, nearly 70% higher than the $650 million level reported in 2021 and formally places Substack in so-called unicorn territory. Substack’s co-founders said the fresh capital will be directed toward enhancing the Substack app, expanding distribution tools and deepening support for writers and other creators as the firm experiments with advertising and content bundles. The company reported surpassing five million paid subscriptions in March and has now secured roughly $200 million since its 2017 founding. As part of the latest deal, BOND partner Mood Rowghani will join Substack’s board of directors.