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Create a batch of SMS messages

POST
/v1/sms/batches
const result = await bird.sms.sendBatch({
  messages: [
    {
      from: "+15557654321",
      to: "+15551111111",
      text: "Hi Alice!",
      category: "marketing",
    },
    {
      from: "+15557654321",
      to: "+15552222222",
      text: "Hi Bob!",
      category: "marketing",
    },
  ],
});
Response202
{
  "data": [
    {
      "id": "sms_01krdgeqcxet5s7t44vh8rt9mg",
      "direction": "outbound",
      "status": "scheduled",
      "to": "+15551234567",
      "from": "+15557654321",
      "text": "Your order has shipped and is on its way.",
      "category": "transactional",
      "requested_language": "pt-BR",
      "resolved_language": "pt-BR",
      "template_id": "smt_01krdgeqcxet5s7t44vh8rt9mg",
      "template_version_id": "smv_01krdgeqcxet5s7t44vh8rt9mg",
      "template_content_hash": "sha256:9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08",
      "segments": {
        "encoding": "GSM_7BIT"
      },
      "cost": {
        "amount": "0.00990",
        "currency_code": "USD",
        "transaction_amount": "0.00790",
        "passthrough_amount": "0.00200"
      },
      "tags": [
        {
          "name": "category",
          "value": "welcome"
        }
      ],
      "options": {
        "smart_encoding": true
      },
      "carrier": "Verizon",
      "mcc_mnc": "311480",
      "last_error": {
        "code": "invalid_destination",
        "description": "Carrier filtered as spam"
      }
    }
  ]
}

Sends up to 100 independent SMS messages in one request. Each item is a complete send request with its own recipient, content, ID, status, and cost. For a single message, use Send an SMS message instead.

Acceptance is all-or-nothing: every item is validated before any is queued, and one invalid item rejects the whole batch with a 422 (nothing is sent). A batch from a workspace with no wallet balance fails with a 402. The 202 response lists the accepted messages in submission order; each delivers asynchronously and is tracked individually, like a single send.

Request Payload

messages
array
required

SMS message send requests, up to 100. Each is an independent send; all are validated before any is queued.

Show child parameters
messages.to
string
required

Recipient phone number in E.164 format (for example +14155550100). One recipient per message. The number is stored and returned in canonical E.164; a recipient that cannot be routed returns a 422 SMSInvalidRecipient.

messages.from
string

Sender to send from. It must be a sender the workspace holds: a number it owns in E.164, such as +15557654321, a short code it holds, such as 24680, or an alphanumeric sender ID it has claimed, such as MyBrand. A sender the workspace does not hold returns a 422 SMSSenderNotConfigured, and an alphanumeric sender must also be permitted, and where required registered, for the destination country. Required on a free-text send and when sending a workspace template. Omitting it in either case returns 422. A built-in template selects its sender automatically and rejects from.

messages.text
string
required

Free-text message body. Required unless template is supplied (the two are mutually exclusive). At least 1 character, up to a 12-segment cap (roughly 1836 GSM-7 or 804 UCS-2 characters). Bird does not truncate; a body exceeding 12 segments is rejected with a 422. The cap applies to segments because GSM-7 and UCS-2 encodings differ in characters per segment.

messages.category
string

Content classification: why you are sending. Required on a free-text send; omit it on a template send, where the category is derived from the template. Where the destination country requires the sender to be registered, a category outside what that registration covers returns a 422 SenderCategoryNotPermitted.

messages.validity_period
integer

Preview feature: how long, in seconds (60-172800), the carrier may keep attempting delivery before the message is marked expired. Currently unavailable; supplying this field returns 422 SMSUnsupportedFeature.

messages.tags
array of object

Structured {name, value} labels for filtering and analytics. Tags become first-class query dimensions: filter the list endpoint by tag name, slice analytics by tag, and surface in webhook payloads. Maximum 20 tags per send. Use tags for low-cardinality dimensions (category, experiment_variant). For arbitrary structured context you do not need as a filter dimension, use metadata instead.

Show child parameters
messages.tags.name
string
required

Tag name. ASCII letters, digits, underscore, and hyphen only. Case-sensitive. Maximum 32 characters.

messages.tags.value
string
required

Tag value. ASCII letters, digits, underscore, and hyphen only. Case-sensitive. Maximum 64 characters.

messages.metadata
object

Arbitrary JSON object stored on the message, returned on API reads, and echoed in webhook payloads. Maximum 2 KB serialized. Use metadata for per-send context like internal IDs and foreign keys. For low-cardinality filterable labels, use tags instead.

messages.options
object

What Bird does to this message on its way out, such as smart_encoding. The message being relayed stays at the top level: its recipient, sender, content, and the delivery instructions the carrier acts on.

Show child parameters
messages.options.smart_encoding
boolean

Replace characters outside the GSM-7 alphabet with their closest GSM-7 equivalent before sending: typically curly quotes, dashes, ellipses, fullwidth forms, and non-breaking spaces.

One such character forces the whole body into UCS2, which more than halves the characters that fit in a segment, so replacing them often lowers the segment count and the cost.

Disabled by default, because it alters the body you composed. The replacement is all-or-nothing: a body that still holds a character outside the alphabet afterwards, such as an emoji or a non-Latin script, is sent exactly as you supplied it. Read the message back to see what was applied: text is the body as sent.

messages.options.track_clicks
boolean

Preview feature: link click tracking. Defaults to false. Currently unavailable; setting this to true returns 422 SMSUnsupportedFeature.

messages.options.max_price_per_segment
number

Preview feature: per-segment price ceiling. Currently unavailable; supplying this field returns 422 SMSUnsupportedFeature.

messages.media_urls
array of string

Preview feature: multimedia (MMS) attachments. Currently unavailable; supplying this field returns 422 SMSUnsupportedFeature.

messages.messaging_profile_id
string

Preview feature: sender selection from a messaging profile pool. Currently unavailable; supplying this field returns 422 SMSUnsupportedFeature.

messages.scheduled_at
string

Preview feature: send-later scheduling. Currently unavailable; supplying this field returns 422 SMSUnsupportedFeature.

messages.broadcast_id
string

Preview feature: broadcast correlation. Currently unavailable; supplying this field returns 422 SMSUnsupportedFeature.

messages.campaign_id
string

Preview feature: campaign correlation for analytics. Currently unavailable; supplying this field returns 422 SMSUnsupportedFeature.

messages.audience_id
string

Preview feature: audience-targeted sends. Currently unavailable; supplying this field returns 422 SMSUnsupportedFeature.

messages.contact_id
string

Preview feature: contact-targeted sends. Currently unavailable; supplying this field returns 422 SMSUnsupportedFeature.

messages.topic_id
string

Preview feature: topic-gated sends. Currently unavailable; supplying this field returns 422 SMSUnsupportedFeature.

messages.personalization
object

Preview feature: per-recipient substitution for batch sends. Currently unavailable; supplying this field returns 422 SMSUnsupportedFeature.

Response Payload

data
array of object
required

One entry per message in the batch, in submission order.

Show child attributes
data.id
string
required

ID of the message, assigned when the send is accepted. Pass it as message_id to the get-message endpoint.

data.direction
string
required

Whether the message was sent from a Bird sender (outbound) or received from a subscriber (inbound).

Possible values: outbound, inbound

data.status
string
required
data.to
string
required

Where the message went. On an outbound message this is the recipient's phone number in E.164 format; on an inbound one it is your own number that received it.

data.from
string
required

Where the message came from. On an outbound message this is the sender you sent it from: an E.164 number, an alphanumeric sender ID, or a short code. On an inbound message, this is the phone number that sent it to you.

data.text
string

The message body. Every message carries body text, attachments, or both, so this is absent only on a received message that carried attachments and no text. For a template send, this is the rendered text after parameter substitution. When category is authentication (a message carrying a one-time code), this is **REDACTED**: the code still reaches the recipient, but the API does not retain it for later reads.

data.category
nullable string

Content classification supplied for free text or derived from the template. Null for inbound messages.

data.requested_language
nullable string
required

The template language requested by the send, in canonical form. Null when the send named no language or used no template.

data.resolved_language
nullable string
required

The template language whose text was rendered, in canonical form. Null when the send used no template. This can differ from requested_language when the template's fallback policy selects another language.

data.template_id
nullable string
required

The template rendered for this message, or null for a free-text message.

data.template_version_id
nullable string
required

The workspace published version or synthetic built-in version rendered at acceptance, or null for a free-text message. For a built-in template, template_content_hash identifies the exact catalogue source.

data.template_content_hash
nullable string
required

The rendered language's source fingerprint, or null for a free-text message.

data.segments
object
required

Segment breakdown for the body.

Show child attributes
data.segments.count
integer
required

Number of segments the body is split into. Each segment is a billable unit.

data.segments.encoding
string
required

Encoding used for the body. The GSM_7BIT encoding fits 160 septets (seven-bit units) in one segment, or 153 per part in a multi-segment message. The UCS2 encoding applies when the body contains a character outside the GSM 03.38 alphabet, including emoji, CJK, and some accented characters. It fits 70 UTF-16 code units in one segment, or 67 per part.

Neither limit counts characters, and both alphabets have characters that cost two units. Under GSM_7BIT there are ten such entries, and they are the whole set: ^, {, }, \, [, ], ~, |, €, and the form feed control. Eighty of those fill a single segment. Under UCS2 an emoji outside the Basic Multilingual Plane is a surrogate pair costing two code units, so 35 of those fill a single segment.

Possible values: GSM_7BIT, UCS2

data.segments.characters
integer
required

Character count of the body, counted in Unicode code points under either encoding. This is not the segment measure: a GSM_7BIT extended-table character counts once here but costs two septets, and a UCS2 emoji outside the Basic Multilingual Plane counts once here but costs two of the segment's 70 code units.

data.cost
nullable object

What the message cost, split into Bird's charge and any third-party fees passed through. Null until the message has been priced.

Show child attributes
data.cost.amount
string
required

Total charged, as a decimal string: the sum of the components below. Net of tax, which applies to your wallet balance rather than to an individual charge.

data.cost.currency_code
string
required

ISO 4217 currency code. Every component is denominated in this currency.

data.cost.transaction_amount
nullable string
required

What we charged to carry the message, as a decimal string. null when this component was not priced; "0.00000" when it priced at zero.

data.cost.passthrough_amount
nullable string
required

Third-party fees we pass on, as a decimal string, such as US 10DLC carrier surcharges. null when this component was not priced; "0.00000" when it priced at zero.

data.tags
array of object

Structured {name, value} filter labels applied to this message.

Show child attributes
data.tags.name
string
required

Tag name. ASCII letters, digits, underscore, and hyphen only. Case-sensitive. Maximum 32 characters.

data.tags.value
string
required

Tag value. ASCII letters, digits, underscore, and hyphen only. Case-sensitive. Maximum 64 characters.

data.metadata
object

Arbitrary JSON metadata stored on the message and echoed in webhook payloads.

data.options
object

The settings applied to this message, with any option you omitted filled in with the default in force when you sent it. Absent on inbound messages, and on any outbound message for which no settings were recorded.

Show child attributes
data.options.smart_encoding
boolean
required

Whether Bird replaced characters outside the GSM-7 alphabet in this message's body with their closest equivalent before sending it. When true, text is the body as sent and segments describes that body.

data.validity_period
integer

Preview feature: how long, in seconds, the carrier may keep attempting delivery before the message is marked expired. Not returned yet.

data.carrier
string

Carrier that handled the message. Absent until a delivery receipt identifies it, and on a received message the carrier reports it only where a carrier fee applies.

data.mcc_mnc
string

Mobile country code and mobile network code of the carrier. Absent until the carrier is identified.

data.last_error
nullable object

Failure detail on a message that failed, was rejected, was not delivered, or expired. Absent otherwise.

Show child attributes
data.last_error.code
string
required

Standardized failure reason:

  • invalid_destination: The number is unassigned, ported out, or malformed.
  • unreachable: The handset is off or outside coverage.
  • blocked_by_carrier: The carrier filtered the message.
  • blocked_by_fraud_protection: Bird fraud protection blocked suspected SMS pumping.
  • blocked_by_recipient: The recipient device blocked the sender.
  • landline_unreachable: The destination is a landline that does not accept SMS.
  • content_rejected: The carrier rejected the content.
  • sender_unregistered: The sender is not registered for the destination.
  • recipient_opted_out: The recipient is on a suppression list.
  • provider_unavailable: The provider remained unavailable after retries.
  • insufficient_balance: The workspace wallet could not fund the send.
  • unknown: The failure could not be classified.

This is an open enum. Accept unrecognized values.

Possible values (may grow over time): invalid_destination, unreachable, blocked_by_carrier, blocked_by_fraud_protection, blocked_by_recipient, landline_unreachable, content_rejected, sender_unregistered, recipient_opted_out, provider_unavailable, insufficient_balance, unknown

data.last_error.description
string
required

The failure in words: the provider's reason text, or Bird's explanation for a fraud protection block or a message refused before submission. Free-form, so branch on code and show this to a human.

data.last_error.carrier_error_code
nullable string

Raw provider-supplied error code, finer-grained than the code that normalizes it. Not a Bird-defined value, so quote it to support when asking why a message failed. Null when the provider sent none, including any failure decided before one was reached.

data.last_error.occurred_at
string
required

When the failure occurred.

data.created_at
string
required

When the message was accepted (outbound) or received (inbound).

data.sent_at
nullable string

When the message was handed to the carrier. Null until then.

data.delivered_at
nullable string

When delivery was confirmed. Null until then.

summary
object
required

Aggregate result for the batch.

Show child attributes
summary.accepted_count
integer
required

Number of messages accepted in the batch. Acceptance is all-or-nothing, so this equals the number of messages submitted.

Related resources

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