Send to Many People

Surge has two mechanisms for sending to multiple recipients: Blasts for one-time sends and Audiences for reusable contact lists. The choice between them depends on whether the same group of people will receive messages more than once.

Blasts vs Audiences

Use a Blast when you have a list of recipients you’re assembling specifically for this send. You pass the recipient list at send time and don’t need to maintain it afterward — weekly flash sales, event announcements, one-time notifications. Use an Audience when the same group of people receives messages regularly. You maintain the audience over time (adding and removing contacts), then blast the whole audience — weekly newsletters, customer cohorts, or geographic segments. Both send the same underlying message; the difference is how you manage the recipient list.

Blasts

Send to a list of phone numbers

The simplest case: pass phone numbers directly in the to array.

from surge import Surge

surge = Surge()

blast = surge.blasts.create(
    account_id="{account_id}",
    from_="pn_01jrzhe8d9enptypyx360pcmxm",
    body="Flash sale: 30% off everything this weekend. Shop at acme.com/sale",
    to=["+18015551234", "+18025551234", "+18035551234"],
)

import Surge from "@surgeapi/node";

const surge = new Surge();

const blast = await surge.blasts.create("{account_id}", {
  from: "pn_01jrzhe8d9enptypyx360pcmxm",
  body: "Flash sale: 30% off everything this weekend. Shop at acme.com/sale",
  to: ["+18015551234", "+18025551234", "+18035551234"],
});

require "surge_api"

surge = SurgeAPI::Client.new

blast = surge.blasts.create(
  "{account_id}",
  from_: "pn_01jrzhe8d9enptypyx360pcmxm",
  body: "Flash sale: 30% off everything this weekend. Shop at acme.com/sale",
  to: ["+18015551234", "+18025551234", "+18035551234"]
)

client = Surge.Client.new(System.get_env("SURGE_API_KEY"))

{:ok, blast} =
  Surge.Blasts.create(client, "{account_id}", %{
    from: "pn_01jrzhe8d9enptypyx360pcmxm",
    body: "Flash sale: 30% off everything this weekend. Shop at acme.com/sale",
    to: ["+18015551234", "+18025551234", "+18035551234"]
  })

curl -X POST https://api.surge.app/accounts/{account_id}/blasts \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "from": "pn_01jrzhe8d9enptypyx360pcmxm",
    "body": "Flash sale: 30% off everything this weekend. Shop at acme.com/sale",
    "to": ["+18015551234", "+18025551234", "+18035551234"]
  }'

Send to contacts

Pass contact IDs (with ctc_ prefix) instead of phone numbers. This links the blast to your contact records for tracking and opt-out management.

blast = surge.blasts.create(
    account_id="{account_id}",
    from_="pn_01jrzhe8d9enptypyx360pcmxm",
    body="Your subscription renews tomorrow. Manage it at acme.com/account",
    to=[
        "ctc_01jrzhe8d9enptypyx360pcmxa",
        "ctc_01jrzhe8d9enptypyx360pcmxb",
        "ctc_01jrzhe8d9enptypyx360pcmxc",
    ],
)

const blast = await surge.blasts.create("{account_id}", {
  from: "pn_01jrzhe8d9enptypyx360pcmxm",
  body: "Your subscription renews tomorrow. Manage it at acme.com/account",
  to: [
    "ctc_01jrzhe8d9enptypyx360pcmxa",
    "ctc_01jrzhe8d9enptypyx360pcmxb",
    "ctc_01jrzhe8d9enptypyx360pcmxc",
  ],
});

blast = surge.blasts.create(
  "{account_id}",
  from_: "pn_01jrzhe8d9enptypyx360pcmxm",
  body: "Your subscription renews tomorrow. Manage it at acme.com/account",
  to: [
    "ctc_01jrzhe8d9enptypyx360pcmxa",
    "ctc_01jrzhe8d9enptypyx360pcmxb",
    "ctc_01jrzhe8d9enptypyx360pcmxc"
  ]
)

{:ok, blast} =
  Surge.Blasts.create(client, "{account_id}", %{
    from: "pn_01jrzhe8d9enptypyx360pcmxm",
    body: "Your subscription renews tomorrow. Manage it at acme.com/account",
    to: [
      "ctc_01jrzhe8d9enptypyx360pcmxa",
      "ctc_01jrzhe8d9enptypyx360pcmxb",
      "ctc_01jrzhe8d9enptypyx360pcmxc"
    ]
  })

curl -X POST https://api.surge.app/accounts/{account_id}/blasts \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "from": "pn_01jrzhe8d9enptypyx360pcmxm",
    "body": "Your subscription renews tomorrow. Manage it at acme.com/account",
    "to": [
      "ctc_01jrzhe8d9enptypyx360pcmxa",
      "ctc_01jrzhe8d9enptypyx360pcmxb",
      "ctc_01jrzhe8d9enptypyx360pcmxc"
    ]
  }'

Schedule a blast

Add send_at to queue the blast for a future time:

blast = surge.blasts.create(
    account_id="{account_id}",
    name="April sale launch",
    from_="pn_01jrzhe8d9enptypyx360pcmxm",
    body="Acme Corp: Our biggest sale of the year starts now. Shop: acme.com/spring",
    to=["+18015551234", "+18025551234", "+18035551234"],
    send_at="2026-06-01T09:00:00Z",
)

const blast = await surge.blasts.create("{account_id}", {
  name: "April sale launch",
  from: "pn_01jrzhe8d9enptypyx360pcmxm",
  body: "Acme Corp: Our biggest sale of the year starts now. Shop: acme.com/spring",
  to: ["+18015551234", "+18025551234", "+18035551234"],
  send_at: "2026-06-01T09:00:00Z",
});

blast = surge.blasts.create(
  "{account_id}",
  name: "April sale launch",
  from_: "pn_01jrzhe8d9enptypyx360pcmxm",
  body: "Acme Corp: Our biggest sale of the year starts now. Shop: acme.com/spring",
  to: ["+18015551234", "+18025551234", "+18035551234"],
  send_at: "2026-06-01T09:00:00Z"
)

{:ok, blast} =
  Surge.Blasts.create(client, "{account_id}", %{
    name: "April sale launch",
    from: "pn_01jrzhe8d9enptypyx360pcmxm",
    body: "Acme Corp: Our biggest sale of the year starts now. Shop: acme.com/spring",
    to: ["+18015551234", "+18025551234", "+18035551234"],
    send_at: "2026-06-01T09:00:00Z"
  })

curl -X POST https://api.surge.app/accounts/{account_id}/blasts \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "April sale launch",
    "from": "pn_01jrzhe8d9enptypyx360pcmxm",
    "body": "Acme Corp: Our biggest sale of the year starts now. Shop: acme.com/spring",
    "to": ["+18015551234", "+18025551234", "+18035551234"],
    "send_at": "2026-06-01T09:00:00Z"
  }'

Audiences

Create an audience

An audience is a named contact list. Create it first, then populate it.

audience = surge.audiences.create(
    account_id="{account_id}",
    name="Premium subscribers",
)

const audience = await surge.audiences.create("{account_id}", {
  name: "Premium subscribers",
});

audience = surge.audiences.create(
  "{account_id}",
  name: "Premium subscribers"
)

# Surge.Audiences isn't typed in the Elixir SDK yet — use the raw client.
{:ok, audience} =
  Surge.Client.request(client, :post, "/accounts/{account_id}/audiences",
    json: %{name: "Premium subscribers"}
  )

curl -X POST https://api.surge.app/accounts/{account_id}/audiences \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Premium subscribers"
  }'

{
  "id": "aud_01jrzhe8d9enptypyx360pcmxz",
  "name": "Premium subscribers"
}

Add contacts to the audience

surge.audiences.add_contact(
    audience_id="aud_01jrzhe8d9enptypyx360pcmxz",
    id="ctc_01jrzhe8d9enptypyx360pcmxa",
)

await surge.audiences.addContact("aud_01jrzhe8d9enptypyx360pcmxz", {
  id: "ctc_01jrzhe8d9enptypyx360pcmxa",
});

surge.audiences.add_contact(
  "aud_01jrzhe8d9enptypyx360pcmxz",
  id: "ctc_01jrzhe8d9enptypyx360pcmxa"
)

{:ok, _} =
  Surge.Client.request(client, :post,
    "/audiences/aud_01jrzhe8d9enptypyx360pcmxz/contacts",
    json: %{id: "ctc_01jrzhe8d9enptypyx360pcmxa"}
  )

curl -X POST https://api.surge.app/audiences/aud_01jrzhe8d9enptypyx360pcmxz/contacts \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "id": "ctc_01jrzhe8d9enptypyx360pcmxa"
  }'

Repeat for each contact, or build this into the workflow that creates or updates contacts.

Blast the audience

Pass the audience ID in the to array.

Surge expands the audience at send time and applies opt-out status automatically — opted-out contacts are skipped, so you never need to filter the list yourself.

blast = surge.blasts.create(
    account_id="{account_id}",
    from_="pn_01jrzhe8d9enptypyx360pcmxm",
    body="Your monthly update from Acme Corp: acme.com/newsletter/april",
    to=["aud_01jrzhe8d9enptypyx360pcmxz"],
)

const blast = await surge.blasts.create("{account_id}", {
  from: "pn_01jrzhe8d9enptypyx360pcmxm",
  body: "Your monthly update from Acme Corp: acme.com/newsletter/april",
  to: ["aud_01jrzhe8d9enptypyx360pcmxz"],
});

blast = surge.blasts.create(
  "{account_id}",
  from_: "pn_01jrzhe8d9enptypyx360pcmxm",
  body: "Your monthly update from Acme Corp: acme.com/newsletter/april",
  to: ["aud_01jrzhe8d9enptypyx360pcmxz"]
)

{:ok, blast} =
  Surge.Blasts.create(client, "{account_id}", %{
    from: "pn_01jrzhe8d9enptypyx360pcmxm",
    body: "Your monthly update from Acme Corp: acme.com/newsletter/april",
    to: ["aud_01jrzhe8d9enptypyx360pcmxz"]
  })

curl -X POST https://api.surge.app/accounts/{account_id}/blasts \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "from": "pn_01jrzhe8d9enptypyx360pcmxm",
    "body": "Your monthly update from Acme Corp: acme.com/newsletter/april",
    "to": ["aud_01jrzhe8d9enptypyx360pcmxz"]
  }'

You can mix audience IDs, contact IDs, and raw phone numbers in the same to array.

Volume caps

Campaign volume limits apply to all sends, including blasts:

Campaign volume	T-Mobile limit
`low`	2,000 SMS segments per day
`high`	Up to 200,000 segments per day (subject to TCR trust score)

Surge queues messages within your daily cap and delivers them in order. If you regularly approach the low cap, request a volume increase through support after your campaign is approved.

Tracking a blast

Blast-level delivery metrics (deliverability rate, opt-out rate) are available in the dashboard under the Blasts section. Per-message delivery status comes through the message.sent, message.delivered, and message.failed webhook events — see Track Message Delivery for the full mechanism.

Get started

Register your business

Sending messages

Receiving messages & webhooks

Phone numbers

Verifications

Channels roadmap

Embeddable UI components

Concepts

Send to Many People

Blasts vs Audiences

Blasts

Send to a list of phone numbers

Send to contacts

Schedule a blast

Audiences

Create an audience

Add contacts to the audience

Blast the audience

Volume caps

Tracking a blast

​Blasts vs Audiences

​Blasts

​Send to a list of phone numbers

​Send to contacts

​Schedule a blast

​Audiences

​Create an audience

​Add contacts to the audience

​Blast the audience

​Volume caps

​Tracking a blast

Blasts vs Audiences

Blasts

Send to a list of phone numbers

Send to contacts

Schedule a blast

Audiences

Create an audience

Add contacts to the audience

Blast the audience

Volume caps

Tracking a blast