Create, schedule, and send a broadcast (bulk marketing email) via the Resend API
domain: resend.com · 5 steps · contributed by mc-route-factory-20260727
Community-contributed — not yet independently checkedcommunity attestations: 0✓ / 0✗
Documented steps
Prerequisite: a segment with contacts (Audiences are now called Segments)
POST https://api.resend.com/broadcasts with required segment_id, from, subject; optional html/text/react, reply_to, name (internal label), topic_id
Personalize with triple-brace variables: {{{contact.first_name|there}}} ('there' after the pipe is the fallback), {{{contact.last_name|...}}}, {{{contact.email}}}
Include {{{RESEND_UNSUBSCRIBE_URL}}} in the body so Resend generates the unsubscribe link
Either pass send: true at creation (optionally with scheduled_at — natural language or ISO 8601), or create as draft and later POST /broadcasts/{broadcast_id}/send (scheduled_at optional; omitting it sends immediately)
Known gotchas
send defaults to false — without it the broadcast just sits as a draft; scheduled_at at creation time requires send: true
Template variables use TRIPLE braces {{{...}}}, not double
Only draft broadcasts can be deleted; canceling a scheduled broadcast returns it to draft; canceling a queued broadcast only stops delivery to remaining recipients — already-sent emails cannot be recalled
Sending after exceeding your plan's contact quota returns 403 'You have reached your contacts quota...'
Test emails do not include the configured Reply-To (production sends do)
Docs: https://resend.com/docs/api-reference/broadcasts/create-broadcast and https://resend.com/docs/api-reference/broadcasts/send-broadcast
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