Castos vs Transistor: private subscribers, apps and price

Castos vs Transistor: the short answer

Castos and Transistor charge the same at each of three tiers, so the choice comes down to limits. As read on October 18, 2026, both sell at $19, $49 and $99 a month, billed monthly (Castos Essentials, Growth and Pro; Transistor Starter, Professional and Business), and at $190, $490 and $990 a year, billed annually. At $49 a month Transistor Professional lists 500 private subscribers against 250 on Castos Growth, but Growth adds the Castos mobile app.

Private subscriber limits and how each host counts them

Castos counts private subscribers, the people who each receive their own private feed: up to 100 on Essentials, 250 on Growth and 500 on Pro. Above 500, Castos adds $50 a month per extra 500, though its pricing page, FAQ and help articles each describe the route differently.

Transistor counts subscribers too, each identified by email address: 50 on Starter, 500 on Professional and 3,000 on Business, with Enterprise above that. Its help center says the numbers are shared by all private shows in an account and that a person on several private shows counts as one. No Castos page states a counting rule for one person on two private shows. Downloads are counted differently too: Transistor says its plans are based on monthly downloads and sends accounts above 250,000 a month to Enterprise, while Castos lists unlimited downloads on every plan.

Listener apps, Spotify and the web player

Castos includes its mobile app from Growth, with a push notification when an episode is ready. Transistor's pages name no branded app: each subscriber gets a personal feed, a dedicated website player and an email notice for each new episode.

Spotify is where they split. Castos says Spotify does not support private feeds. Transistor offers Spotify Open Access, Spotify's way of connecting a host's private feeds, on all plans, and its subscribers need their own Spotify account. Spotify's own help lists Transistor among its Open Access platforms and does not list Castos.

Team seats, single sign-on and enterprise plans

Team members are the people you invite to publish. Castos allows just you on Essentials, up to 5 on Growth and up to 10 on Pro, and Transistor allows unlimited team members on every plan. Castos lists single sign-on on Castos Premium only, so ask whether it covers listeners or only account holders. Transistor's pages read name no single sign-on, and its Enterprise plan starts from $199 a month, contact Transistor.

Who should pick Castos and who should pick Transistor

Pick Castos for 100 private subscribers at $19 a month, billed monthly, where Transistor Starter lists 50, and for an app that follows your subscriber list from Growth. Castos's fair use policy describes Essentials as built for individual creators and small teams, and the app starts on Growth. The Castos review has each plan's limits.

Pick Transistor for 500 private subscribers on Professional or 3,000 on Business at the same prices, for unlimited team members, or for Spotify listening. Libsyn, on its own page about Transistor alternatives, names private podcasting for an internal corporate team as a reason to choose Transistor.

Both hosts offer 14 days; Castos asks for a card when the trial starts and does not charge it until the 14 days are up, and Transistor's pricing page does not say either way. See private podcast hosting cost and does Spotify allow private podcasts.