Two-way SMS and MMS on every DID

Inbound SMS — every DID, by default

Every SMS-capable DIDHub DID receives inbound SMS automatically. Route the inbound to:

• Webhook — your endpoint receives a POST with sender, body, timestamp, MMS attachments. Common for chat/CRM integrations.
• Email — SMS forwards to a configured email address. Common for low-volume support inboxes.
• SIP MESSAGE — SIP-native delivery to your PBX or softphone. Used by 3CX, FreePBX, Asterisk for in-app SMS.
• SMS-to-Slack/Teams — via webhook + your team's bot platform.

Inbound SMS is included in the monthly DID rental — no per-message charges for receiving.

Outbound SMS — registered, compliant, scalable

Outbound SMS varies dramatically by country in 2026. The era of unrestricted outbound SMS ended around 2020-2022 as regulators across major markets cracked down on spam. DIDHub handles the country-specific compliance for you, but the rules vary:

DIDHub manages the registration paperwork. You give us your business info, expected message volume, and templates; we file the registrations and you go live once approved. Most customers go from signup to compliant outbound in 1-3 weeks depending on country.

MMS support

MMS (Multimedia Messaging Service) is supported on US/CA local and toll-free, UK 07xxx, and a growing list of EU mobile DIDs. Standard MMS attachments — images, PDFs up to 1MB — are handled inline; larger attachments are returned as a download URL.

For markets without native MMS, DIDHub falls back to URL-based image delivery in SMS body — most modern handsets render the URL as a tap-able preview.

API surface

SMS and MMS are first-class in the DIDHub REST API. The four primary calls:

# Send SMS
POST /v1/sms/send
{"from": "+15551234567", "to": "+447700123456", "body": "Hello from DIDHub"}

# Receive SMS via webhook (configured per-DID)
POST https://yourapp.com/sms-inbound
{"from": "...", "to": "...", "body": "...", "timestamp": "..."}

# Send MMS
POST /v1/mms/send
{"from": "+15551234567", "to": "+15555551212", "body": "...", "media": ["https://..."]}

# Status delivery receipts
GET /v1/sms/{id}/status

See the API section on the homepage for SDK quickstarts in Node, Python, Go, and PHP.

Per-country SMS notes

Some countries require special handling worth knowing about:

• India: DLT registration is template-based. Every SMS template must be pre-registered with TRAI; sending a non-registered template fails. Marketing-vs-transactional categorization matters for delivery routing.
• US 10DLC: brand + campaign registration. Per-day throughput limits apply per campaign. DIDHub manages the throughput pool.
• UAE / Saudi: sender ID approval is content-sensitive. DIDHub provides templates that pass first-time approval.
• China: outbound SMS to Chinese mobile numbers is heavily restricted. Inbound-only is the standard for production use.
• Israel: light regulation. Most templates pass without trouble.

Frequently asked questions