Product updates

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Inboxes

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Improvements

• Rotating an inbox credential now tracks the provider credential ID directly, so stale credentials can be cleaned up more reliably.
• Mailbox roles now use the current managed-mailbox permission model for sending, receiving, and inbox access.

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Bug fixes

• Inbox provisioning now recovers more safely if external credential creation succeeds but the local operation has to retry.

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Bug fixes

• Creating a mailbox on the shared Sendmux domain now checks the shared-domain setup before provisioning the mailbox, so generated addresses no longer fail when required domain records are missing.
• Domain creation and deletion now consistently protect the shared Sendmux domain while still letting teams delete the mailboxes they created.
• Sign-up legal links now use shorter labels so the agreement line fits better on narrow screens.

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Bug fixes

• Sign-up, email verification, and checkout tracking now handles redirects more reliably.
• Sensitive URL parameters are now removed from tracked page and referrer metadata.
• A growth reporting view now loads grouped activation and revenue metrics without failing on aggregate sorting.

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Dashboard

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Inboxes

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Improvements

• Delivery log statuses now show short readable labels instead of raw provider event strings.
• Dashboard hover details now avoid repeating the same health summary in more than one place.
• Billing runway and usage-capacity cards now use clearer labels and more predictable interactions.

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Bug fixes

• Draft autosave now backs off while a message is sending, reducing duplicate saves and avoidable rate-limit warnings.
• Email buttons now render with a consistent background across email clients.
• Deliverability alerts now count bounce rate and complaint rate separately when both need attention.

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Dashboard

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Improvements

• Status blocks now use filled healthy, warning, and issue states in light and dark mode.
• Health details now stay concise on hover, with exact timestamps available where timing matters.

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Bug fixes

• Quiet inbound periods no longer count as active issues when there is no mail to receive.
• Activity date labels now stay stable instead of shifting by timezone.

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Dashboard

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Improvements

• The health strip now fills completed hours and shows the selected hour’s sent, received, and failed counts directly in the summary.
• Activity chart tooltips now match the dashboard style and stay compact while you inspect daily sending and receiving totals.
• Domain status now uses the latest saved verification details so SPF, DKIM, and DMARC signals can be shown independently after checks run.

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Bug fixes

• Empty or low-activity teams no longer show misleading healthy indicators, fake billing runway, or internal dashboard wording.
• Duplicate API key names no longer trigger repeated-row rendering warnings in the overview.

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Improvements

• The sending API and supporting test packages now use updated dependency versions that resolve current npm security advisories without changing the public API.

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Dashboard

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Improvements

• The API reference now uses cleaner operation names and shared response models, improving generated SDK method names and response types.
• The Inboxes sidebar item now shows an unread count when new mail is waiting.
• The dashboard sidebar now separates feedback from account top-up controls more clearly.

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Bug fixes

• Email threads in Inboxes now keep message bodies readable in dark mode, including replies with their own text colours.

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Improvements

• New teams now start on the managed Amazon SES sending route with a 50-email daily limit before requesting a review.
• Inboxes now let you move conversations into another folder from the context menu when that folder accepts mail.
• The Inboxes compose window now turns completed recipients into tidy address chips after you move out of the field, while leaving unfinished input untouched.
• The Compose button now sits above the inbox folder list for faster access.
• Sending and receiving log tables now show relative times with the full date and time available on hover.

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Bug fixes

• Long inbox threads now scroll inside the message reader instead of making the whole app page taller.
• Closing a compose window with draft content now saves the pending draft before closing, while Discard still skips saving.

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Improvements

• The dashboard sidebar now narrows on smaller screens and keeps Documentation, Feedback, balance, and Top up inside the scrollable menu.
• The Inboxes page now gives more room to the open message on narrower desktop screens while keeping the folder menu and conversation list usable.

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Bug fixes

• Sending and receiving log tables now fit typical browser widths without unnecessary horizontal scrolling.
• Long message IDs in log tables now show a short readable prefix, so columns stay aligned while the full value remains available.
• Drafts now autosave once the basic message details are present, and the Drafts count updates after the first save.
• Inbox folder counts now only appear where they are meaningful: unread Inbox, all Drafts, and all Spam.
• Mailbox filters now hide inactive or deleted mailbox addresses.
• Incoming log senders now show the message sender instead of a message identifier.
• The Compose keyboard hint is now easier to read.

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Incoming logs

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Dashboard

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Improvements

• Webhook event selection now includes search, making it faster to choose the right events when setting up or editing a webhook.
• The dashboard setup checklist now adapts better on small screens and keeps long task lists within the viewport.

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Bug fixes

• Inbox message bodies now use the selected light or dark theme, so rendered email content no longer appears with mismatched colours.
• Draft conversations now open in edit mode from the Drafts folder, and edited drafts replace the previous draft when saved or sent.
• Sent-folder conversations now sort by sent time and show the message from the selected folder instead of mixing in unrelated thread messages.
• Inbox actions such as archive, delete, spam, and not spam now apply to the messages in the current folder, avoiding unexpected moves for the rest of the conversation.

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Inboxes

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Labels

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Improvements

• Mail actions now show progress with a subtle fade and status toast, so the inbox stays readable while an action completes.
• The dashboard sidebar now has separate icons for Inboxes and Mailboxes.
• The sidebar credit balance now stays usable in both expanded and collapsed modes.
• Thread replies now refresh into the open conversation after sending.
• Inboxes now refresh quietly in the background while the tab is visible, so new mail and folder counts stay current without interrupting your work.
• The compose window now supports Command + Enter to send, with the shortcut shown on the send button.
• Mailbox switchers now include search, so teams with many mailbox addresses can switch faster.
• New teams now get an in-dashboard setup checklist that helps choose a sending, receiving, or combined workflow and tracks the key setup steps.
• Mailbox quota bars now show live storage usage on the mailbox list instead of always showing zero usage.

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Bug fixes

• Folder-specific actions now hide when they do not apply, such as spam actions for drafts.
• Archive, spam, and delete actions now resolve the available mailbox folders before moving messages.
• Attachment downloads now preserve the original file bytes and metadata.
• Slow inbox actions now time out cleanly instead of leaving the page stuck in a processing state.
• Reply sends now move out of drafts correctly after queuing.
• Delete actions now create or use a Trash folder so deleted conversations remain accessible from the inbox folder list.
• Label changes no longer alter the mailbox colour marker shown beside each conversation.
• Inbox send confirmations now use the same action-toast styling as other message actions.
• Opening an unread conversation now clears its unread styling and folder count immediately, then refreshes quietly in the background.

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Team setup

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Dashboard help

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Mailboxes

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Bug fixes

• The consultation calendar loading state now separates the spinner from the loading text.
• The final Open dashboard action now opens the new team’s dashboard overview.
• The use-case field label now has the same spacing as other setup fields.
• The dashboard feedback form now opens with the intended wider layout, app typography, and reliable submission handling.
• Creating the first mailbox password now recovers cleanly if part of the operation is interrupted.
• Mailbox setup now waits for new mailbox accounts to be ready before applying sender details and creating the first password.
• If mailbox password setup needs extra time, the generated password is still shown once instead of creating a credential you cannot see.
• Recreating a deleted mailbox address now rebuilds sender rules reliably, so the new mailbox is created instead of showing a retry error.
• Rotating or revoking a mailbox password now avoids leaving the mailbox without a working credential if part of the change needs to retry.
• Mailbox password changes now count in-progress credentials toward the team API key limit, so limits stay consistent while a change is being processed.
• Deleting and recreating the same mailbox address now works without old mailbox state blocking the new mailbox.

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Team setup

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Sending account management API

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Mailbox suspension

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Mailbox API attachments

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Improvements

• The Sending API docs now link directly to the account-management endpoints that control which accounts can send.
• The Management API reference now has a dedicated Sending accounts group.

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Bug fixes

• Mailbox credentials now stop working while their mailbox is suspended and work again after resume.
• Sending from a suspended mailbox address is now blocked even when you use a broader sending credential.
• Oversized uploaded attachments are now rejected before they can be used in a send request.
• Oversized outbound messages are now rejected before partial send work starts, so clients get a clear payload_too_large response instead of a later send failure.

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Inbound email billing

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Realtime mailbox events

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Team limits

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Improvements

• Limit usage now appears at the bottom-right of the relevant dashboard pages, so it stays available without crowding the page header.
• The API key limit now covers active root, sending, and mailbox credentials.
• The team limits guide now clarifies default limits, increase requests, and that email volume is not capped beyond existing sending limits.
• Webhooks and mailbox realtime events use the same public message.received event names for inbound mailbox activity.

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Bug fixes

• Mailbox credential creation and rotation now respect the API key limit consistently.

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Dashboard

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Improvements

• Mailbox lists now show Name before Email, with clearer column labels.
• Long domain, mailbox, and webhook headings now stay on one line with cleaner truncation.
• Long webhook endpoint URLs are clipped in lists and can be inspected from the hover tooltip.
• Team menus now include a direct Invite members action.

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Bug fixes

• Invited team members are now taken into the invited team after accepting or signing up from an invitation, instead of being sent to create a new team.
• Pending team invitations now appear in invitation history.
• Pending team invitation banners now clear immediately after accepting or declining, without requiring a hard refresh.
• Users with pending team invitations can now view and accept them without creating a separate team first.
• Webhook 24h metric cards and charts now count recent deliveries consistently with the delivery log.
• Sidebar account initials now come from the signed-in user’s name or email.

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Webhooks

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Improvements

• Webhook delivery logs now show attempts, retry timing, response status, latency, response previews, and retained request payloads from the last 7 days.
• Failed-webhook emails now link directly to the delivery logs for the affected subscription.
• Public event names now use product-shaped message.* names, including message.received and message.received.spam.

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Mailbox API

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Improvements

• Session discovery now reports supported Mailbox API capabilities, current state tokens, request limits, and intentionally unavailable features.
• Message responses now expose active keywords, and batch message updates can set or clear custom keywords for richer mailbox triage.
• Batch message deletes can move up to 100 messages to Trash, or permanently delete them when requested.
• Mailbox credentials now have tighter permissions so restricted mailbox capabilities stay unavailable outside the public API. They remain usable for SMTP and IMAP access.

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Mailbox API for agents

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Improvements

• Message searches support richer filters and snippet-only responses so clients can decide what to fetch next.
• Sync now covers messages, folders, threads, submissions, identities, and quotas through typed change polling.
• Message and folder writes now have stronger stale-state protection, with If-Match support on supported deletes as well as updates.
• Attachment sends can now use a binary upload step before messages/send, and attachment downloads support byte-range requests.
• Attachment contents remain download-only; clean content endpoints return attachment metadata without parsing files.

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Managed Amazon SES sending route

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New mailbox API

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Improvements

• One credential per mailbox. Each mailbox now uses a single credential for sending and for mailbox access over SMTP, IMAP, and the API — simpler setup. “App passwords” are now called “Mailbox passwords”.
• Refreshed, more compact Accounts, domain, mailbox, and webhook pages, with DNS records and connection settings you can copy in a single click.

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Bug fixes

• The mailbox quickstart example now works exactly as shown.

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Management API

• Consistent success and error response formats.
• A request ID on every response for support correlation.
• Cursor pagination on all list endpoints.
• ETags and conditional requests (If-None-Match / If-Match) to save bandwidth and prevent lost updates.
• Idempotency keys so create requests can be retried safely.
• Rate-limit responses now report the exact number of seconds until your limit resets.

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Bug fixes

• Fixed a rare timing issue that could cause a small number of valid emails to be incorrectly rejected; affected messages now send normally.

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Mailboxes

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Your own sending domains

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Configurable webhooks

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Deliverability

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Bug fixes

• Delivery, bounce, and complaint events are now recorded reliably to your event history.
• Delivery-log statuses stay accurate even when provider events arrive out of order — a failed or bounced email is no longer shown as sent.

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Team deletion

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Invitation management

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Team roles

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Low-balance email alerts

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Improvements

• Refreshed, on-brand transactional emails — responsive, dark-mode friendly, and personalised with your name.
• The overview now tracks pending emails alongside sent, successful, and failed, and large numbers are shown compactly (for example 1.5k, 2M).
• The dashboard and logs refresh automatically while you’re viewing them and pause when the tab is in the background.

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Sendmux is here

• Dashboard — an at-a-glance overview with sending charts and a searchable, filterable delivery-log viewer with CSV export.
• Sending accounts — connect accounts over SMTP or with Gmail and Microsoft 365 (including GCC High, DoD, and China clouds), organise them into groups, bulk-test connections, and import in bulk from CSV. See Sending accounts.
• Sending API — send a single email or batches of up to 100 over a modern JSON REST interface, with structured sender and recipient objects, partial-success batch results, attachments, CC/BCC, and Reply-To. See the Sending API.
• Read-only Management API — query your sending accounts, email logs, metrics, and billing programmatically, with API-key authentication and a published OpenAPI spec.
• Scoped API keys — restrict a sending key to specific accounts or a group, and see warnings before deleting anything a key depends on.
• Dollar-based billing — a clear transaction history, automatic top-ups so your balance never runs dry, and promotion codes at checkout.
• Unlimited teams — create and join as many teams as you need.