Social Capital and American Express Ventures backed Simplee, a startup that aims to facilitate medical bill payments, in its latest $20 million funding round.

Simplee says it works with over 900 hospitals and physicians and helps process “over $1 billion in annual payments” in the U.S.

“Simplee has developed a smart technology platform that reduces the friction in healthcare payments, an increasingly complex ecosystem to navigate,” said Amex’s Harshul Sanghi. “We’re pleased to invest in solutions that provide a more seamless experience for patients and providers alike.”

83North and Heritage Group also participated in the investment, which including its seed round brings funding up to at least $37.8 million for Simplee.

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