Chargebee - Chargebee lets you manage subscriptions and payments at scale, handle custom recurring billing scenarios, reduce subscription churn and simplify accounting.

Donorhut - Donorhut offers cloud fundraising software for charities and non-profits of any size.

Recurly - Subscription billing and recurring billing management. Recurly offers enterprise-class subscription billing for thousands of companies worldwide.

Txt2Give - Txt2Give helps churches, non-profits, schools, alumni associations, and political campaigns receive donations with text messages.

Zuora - Zuora creates cloud-based software on a subscription basis that enables any company in any industry to successfully launch, manage, and transform into a subscription business.

Little Green Light - Illuminating Data. Advancing Nonprofits.