What's new in May 2026

Audience API Write Endpoints Replace Three Nested Routes

The audience API can now create, update and delete segments, topics and properties, update lists and contacts, and create contacts in bulk.

A contact can be added to or removed from a list or a topic, and lists can also be added to or removed from many contacts at once, or deleted in bulk. Writes need the audience:write scope and don't work with sandbox API keys; reads need audience:read.

Three nested endpoints were removed in favour of filters. GET /audience/lists/{id}/contacts and GET /audience/segments/{id}/contacts are now GET /audience/contacts?list_id= and ?segment_id=, and GET /audience/lists/{id}/segments is now GET /audience/segments?list_id=.

The contacts list response changed from {contacts, total, page, per_page} to {contacts, pagination: {…}}, and the lists inside a contact no longer include contacts_count. Check these changes in any integration built before May.

Topic Opt-In And Opt-Out Defaults Corrected

A topic set to opt_out now subscribes new contacts automatically and opt_in requires them to subscribe, the reverse of how both used to work.

The setting was implemented backwards, and the app's own descriptions matched the wrong behaviour. The fix applies to contacts created through the API, CSV import and the app.

Stored topics were not changed, so every existing topic now behaves the opposite way from before. Check the setting on every topic before the next send.

Segment AND And OR Rules Corrected In The API Reference

The API reference now says conditions within a group are joined by OR and groups by AND, which is how segments have always worked.

The reference used to say the opposite. Only the text was wrong: segments and the app's own labels always worked this way, so existing segments have not changed and don't need saving again.

Segments built by following the reference instead of the segment builder match the opposite of what was intended, so check them. We're sorry for the time this cost.

Automatic Unsubscribe Footer And List-Unsubscribe Headers On Campaigns

Every campaign now has an unsubscribe link and one-click unsubscribe headers, even when the email has no unsubscribe tag.

When the HTML contains neither {{unsubscribe_link}} nor {{unsubscribe_url}}, a short footer is added at sending time, and the saved email is not changed. Every campaign also sets List-Unsubscribe and List-Unsubscribe-Post, so the one-click unsubscribe button works in Gmail and Apple Mail.

The footer can't be turned off; adding your own unsubscribe tag is the way to replace it. The campaign editor shows a banner with an “Insert link” button when the tag is missing, and warns before saving an email without one.

Unsubscribe Confirmation Page With Reasons And Resubscribe

The unsubscribe link in an email now opens a page that asks for confirmation, instead of unsubscribing the recipient as soon as the page loads.

Recipients can pick a reason (too many emails, not relevant, never signed up, or their own text), which is saved in the contact's history. After unsubscribing, the page offers a one-click way to subscribe again, since many of these clicks are accidents.

The one-click unsubscribe in the mail client still unsubscribes right away, as the standard requires.

Unsubscribe And Web Version Pages In 19 Languages

The unsubscribe and web version pages now show in the recipient's language, in 19 languages, where they used to be English only.

The language comes from the contact's communication language, then from a team default the owner sets in Team settings → Overview, then English. Only the page around the email is translated: the email itself is shown as written, and the default unsubscribe footer added to campaigns stays in English.

Arabic and Hebrew are not included yet, because the pages don't support right-to-left text. Unsubscribe reasons are saved the same way whatever language the recipient saw, so they can be compared across languages.

Emailed Confirmation Codes For Sensitive Actions On SSO Accounts

Accounts that sign in with Google or GitHub now confirm sensitive actions with a six-digit code sent by email.

These accounts used to skip the check entirely when changing the password or account email, turning two-factor authentication on or off, or deleting the user or a team. The code is valid for 10 minutes, and one confirmation covers all of these actions for 15 minutes. Accounts with a password still confirm with it.

Changing the account email now sends the verification email again; it used to mark the account unverified with nothing to click. Password fields on sign-up, password reset and settings also show a live checklist of the rules: at least 12 characters, upper and lower case, a number and a symbol.

Campaign Test Sends Use The Production Sending Path

Campaign test sends now go through the same sending path as the real campaign, so they show what recipients will get.

Tracking is on, and the unsubscribe and web version links work, opening preview pages that change nothing. The “Send test” button in the editor opened from a campaign now uses the same path; it used to send without the unsubscribe footer or web version link, and with the wrong sender and subject.

Boolean Segment Conditions No Longer Require A Value

Segment conditions on true/false properties (is_true and is_false) no longer require a value.

Every condition used to require one, so a condition on a true/false property was rejected, both through the API and in the app's segment builder.

Plan Contact Limit Check Before A Campaign Is Sent

The campaign editor now shows an “Upgrade required to send” dialog with your contact count and plan limit when a send would go over the limit, instead of failing during the send.

Duplicate Action For Segments

The row menu on the Segments list has a new Duplicate action that copies a segment's conditions and list, then opens the copy.

CSV And JSON Export Of Domain DNS Records

A new “Send to developer” menu on each domain page downloads the DNS records the domain needs as CSV or JSON.

It works for sending, tracking, inbound and storage domains, and uses the domain's own values from the page.