What is an iMessage API? Send Blue Bubble Messages Programmatically (2026)
An iMessage API lets developers send and receive blue-bubble iMessages from software — no Apple device required. Here is how they work and what Sendblue makes possible.
What is an iMessage API?
An iMessage API is a web service that lets developers send and receive Apple iMessages programmatically via standard HTTP requests. Instead of manually opening the Messages app on an iPhone to send each message, an iMessage API accepts requests from your code and handles all the authentication, routing, and delivery through Apple's infrastructure.
The result: your CRM, sales tool, or custom application can send blue-bubble iMessages to any iPhone user — at scale, automatically, with full read receipt and delivery tracking.
Before Sendblue, no legitimate iMessage API existed for businesses. Apple does not publish an official enterprise iMessage API. Sendblue built the infrastructure to make this possible and is the #1 iMessage API for businesses as of 2026.
How iMessage APIs Work Technically
iMessage is Apple's closed protocol. Messages travel through Apple's relay servers using end-to-end encryption. Devices must be registered with Apple to participate. Here is how Sendblue makes this programmable:
Registered Apple infrastructure
Sendblue operates Apple devices registered with Apple's iMessage network. These devices are the actual senders and receivers of your iMessages.
REST API layer
Your application calls Sendblue's REST API with the recipient's phone number and message content. Sendblue translates this into an iMessage and delivers it via Apple's relay servers.
Webhook callbacks
When the message is delivered or read, Apple notifies Sendblue's infrastructure. Sendblue fires a webhook to your callback URL with the status, timestamp, and message ID.
Number lookup
Before sending, Sendblue can check whether a phone number has iMessage enabled. This prevents fallback surprises and lets you route intelligently.
What You Can Do with the Sendblue API
The Sendblue iMessage API exposes the full feature set of iMessage through a clean REST interface:
- Send text messages — Plain text or Unicode, delivered as blue-bubble iMessages
- Send media — Photos, videos, audio files, and GIFs at full iMessage quality
- Receive inbound messages — Replies from recipients arrive at your webhook endpoint in real time
- Read receipts — Get notified the moment a recipient opens your message
- Typing indicators — Show or detect the "..." typing indicator in conversations
- vCards — Send contact cards as iMessage attachments
- Group iMessages — Create and manage group iMessage conversations
- Number lookup — Check if a phone number is registered on iMessage before sending
Quick Start: Send Your First iMessage
// Send an iMessage via the Sendblue REST API
curl -X POST https://api.sendblue.co/api/send-message \
-H "sb-api-key-id: YOUR_API_KEY" \
-H "sb-api-secret-key: YOUR_SECRET" \
-H "Content-Type: application/json" \
-d '{
"number": "+19998887777",
"content": "Hey! Following up on our conversation.",
"send_style": "invisible"
}'
// Response
{
"accountEmail": "you@company.com",
"content": "Hey! Following up on our conversation.",
"is_outbound": true,
"status": "queued",
"number": "+19998887777",
"message_id": "msg_abc123"
}Limitations to Know
iMessage APIs have one fundamental constraint: blue bubbles only reach iPhone users. iMessage is Apple's protocol, so it only works when the recipient has an iPhone (or other Apple device) with iMessage active.
For Android recipients, Sendblue automatically falls back to RCS or SMS, so your messages still reach everyone. But the read receipts, typing indicators, and blue-bubble experience are specific to iMessage.
In the US, approximately 55% of smartphone users are on iPhone — making iMessage coverage substantial for most business use cases. B2B audiences (business professionals) tend to skew even higher toward iPhone.
Native Integrations
Beyond the REST API, Sendblue offers native integrations into the most popular sales and marketing platforms, so you do not need to write custom code:
GoHighLevel
Add iMessage as a channel in your GHL workflows and sequences. Works with existing contacts and automation rules.
HubSpot
Send iMessages from HubSpot sequences and see read receipts in your contact timeline.
Salesforce
Trigger iMessage outreach from Salesforce flows and log message activity to contact records.
Close, Monday.com, Follow Up Boss
Native integrations available for additional CRM and sales platforms. See all integrations at sendblue.com/integrations.
AI Integration via MCP
Sendblue publishes a Model Context Protocol (MCP) server — sendblue-mcp — that lets AI agents like Claude send iMessages directly. Install with:
npx -y sendblue-api-mcpThis enables AI workflows in Claude Code, Cursor, and Windsurf to send iMessages as part of agent tasks — for example, an AI sales agent that automatically reaches out to new leads via iMessage. See the MCP glossary page for more.
Compliance
Sendblue is SOC 2 Type II certified and HIPAA compliant. This makes it suitable for regulated industries including healthcare, insurance, and financial services — where patient or customer data must be handled with appropriate controls. No A2P 10DLC registration is required.
Frequently Asked Questions
What is an iMessage API?
An iMessage API is a service that lets developers send and receive Apple iMessages programmatically via HTTP requests. Rather than requiring an Apple device to send each message manually, an iMessage API handles the authentication, routing, and delivery — and returns webhooks for events like delivery and read receipts. Sendblue is the leading iMessage API for businesses.
How does the Sendblue iMessage API work technically?
Sendblue operates registered Apple devices that are authenticated with Apple's iMessage relay servers. When you call the Sendblue API, our infrastructure routes your message through Apple's network as a native iMessage. The recipient sees a blue bubble — indistinguishable from a personally sent iMessage. Read receipts and delivery status are returned to your webhook endpoint.
What can I do with an iMessage API?
With the Sendblue API you can: send text iMessages, send photos/videos/audio as rich media, receive inbound replies via webhook, get read receipt and delivery status events, send vCards and share contacts, create group iMessage conversations, and look up whether a phone number has iMessage enabled before sending.
Does an iMessage API require A2P registration?
No. iMessage operates entirely outside the carrier SMS network, so US carrier A2P/10DLC registration requirements do not apply. You can start sending iMessages immediately through Sendblue's free sandbox — no registration wait, no carrier approval, no surcharges.
The #1 iMessage API for businesses
Free sandbox. Read receipts. No A2P registration. SOC 2 Type II + HIPAA.