Where a subscriber came from is now a first-class filter on audiences and automations.

One-to-many actions, a dedicated settings page, richer analytics, and previews that let you see how an automation would have performed in the past.

On patching a 1981-era system mid-flight

Two new filters and columns for keeping tabs on bouncing subscribers — even before they're marked undeliverable.

Metadata, transactional emails, and integrations now require a paid plan for new accounts — existing users are exempt.

Attack mode, embedded fingerprinting, and denied user agents — three new ways to keep spam out of your newsletter.

X.400 said what must be possible. SMTP said what must be done.

Your newsletter can make your company feel like a local small business.

One fewer setting to deal with! (Maybe)

Gate your archive content behind a subscription — no paid plan required.

Gather round while an old man yells at cloud (email)

While other projects floundered in red tape, email thrived in it.

Our public postmortem for the incident on March 31st, 2026.

The email feature that got added because people kept marking email newsletters as junk.

Share book recommendations with rich embeds from Bookshop.org

It turns out you’ve been using agents since way before the AI variety started deleting everything in their owners’ inboxes.

Skip the password entirely and sign in with just your passkey.

"First name" and "first_name", together at last

Updated DPA, privacy policy, sub-processor list, and cookie policy.

Honestly, it’s more conceptually complicated than technically complex.

Use your fingerprint, face, or security key as a second factor when signing in.

A deep dive into our date-based API versioning system, inspired by Stripe, and how it lets us ship breaking changes without breaking your integrations.

The first email was sent from space three days after the first webpage was published.

A new API version that defaults to draft instead of sending, with a one-time confirmation header for immediate sends.

Invisibly making your newsletter safer

If you lose your authenticator device, recovery codes let you get back into your account.

Quickly find your best (and worst) performing emails by filtering on open rate, click rate, and delivery rate.

Making every ID in our API self-describing, one endpoint at a time

The machinery behind Buttondown's link checker is more involved than you might expect.

Mailing lists died out to make way for newsletters. But there are a lot of reasons to bring back group discussions over email.