Importing an Infobip phone number into Azure Communication Services

Question

Importing an Infobip phone number into Azure Communication Services

Stephen Sutherland 20

I'm trying to set up a SMS forwarding service in Azure Communication Services. As I'm UK based, Azure pushes me towards Infobip as a vendor of a phone number compatible with ACS.

I've purchased a number from Infobip but it doesn't seem to be recognised in ACS as a phone number available to add? What am I missing? How do I get ACS to recognise that a phone number if available from Infobip?

I have an API Key from Infobip but can't see where I would connect Azure to Infobip or enter the API?

Any help appreciated!

Ajay Rathod 440 Reputation points Microsoft External Staff Moderator

2026-09-02T22:12:59.96+00:00

Hello Stephen,

You purchased a number from Infobip on the understanding that it could be attached to your ACS resource, and it has not appeared as an available number. You are also looking for the place in Azure to enter your Infobip API key. I have confirmed both behaviours against current product documentation, and I can tell you exactly why neither is working. Root cause - confirmed. Azure Communication Services has no import or bring-your-own-number capability for SMS; direct routing covers voice only. Infobip numbers are supported solely through Messaging Connect, which is currently in Public Preview and has no SLA. Messaging Connect binds your ACS resource to the partner account at the start of the flow, so the purchase must be initiated from the Azure portal. Because your number was bought at Infobip independently, it was never associated with your ACS resource, and there is nothing for Infobip to sync back. Separately, the Infobip API key is by design never entered into Azure - Microsoft does not store, log or persist partner credentials; the key is supplied on each send request and discarded immediately afterwards. Step 1: In the Azure portal, open your Communication Services resource, go to the Messaging Connect blade, select Infobip and accept the terms. Why this matters: this is the step that creates the link between your ACS resource and your Infobip account. How to verify: you are redirected to Infobip's portal. If the blade is unavailable, confirm a paid subscription (free credits are not eligible) and Owner or Contributor rights. Step 2: Contact Infobip and ask them to associate your existing number with the ACS-linked account and trigger the sync, rather than buying a second number. Their guide: https://www.infobip.com/docs/integrations/microsoft-azure-acs-messaging-connect Why this matters: only partner-synced numbers surface in ACS. How to verify: the number is listed under ACS > Phone numbers with a populated "Operator Name" column. Approval and activation timelines are set by Infobip; Microsoft is not involved in vetting, and instant provisioning is not supported. Step 3: Generate the API key at https://portal.infobip.com/dev/api-keys using Create New API Key, and enable the API scope sms:message:send. Pass it per request in the messagingConnect object with partner set to "infobip". Why this matters: without this object a Messaging Connect number is rejected with 400 "MessagingConnect option isn't provided"; a mismatch returns 400 "MessagingConnect option isn't matching with the number information"; an unassociated sender returns 401. How to verify: a test send returns a message ID and a delivery report arrives via Event Grid. Step 4: Pin the supported preview versions - API 2025-05-29-preview, JavaScript SDK 1.2.0-beta.4, .NET SDK 1.1.0-beta.3. Why this matters: Python and Java SDKs do not yet support Messaging Connect, and older client versions do not expose the option at all. How to verify: your installed package version matches the beta above exactly. Recommended alternative. For a UK-only SMS forwarding service, ACS sells UK Mobile numbers directly with Send SMS and Receive SMS both at General Availability, which gives you two-way messaging without a partner and without preview risk. Requirements: a paid subscription (Azure free credits and Azure Prepayment are never eligible) on Pay-As-You-Go, Modern Customer Agreement, CSP or Enterprise Agreement, with a billing location in Australia, Belgium, Denmark, Finland, Ireland, Latvia, Netherlands, Poland, Sweden, the United Kingdom or the United States. Acquire it from ACS > Phone numbers > Get, country United Kingdom, number type Mobile. UK Toll-Free and Local numbers are voice only and will not work for SMS. Cost note. On Messaging Connect, Microsoft charges a 0.0025 USD platform fee per SMS send request, applied whether or not the message is delivered. Infobip bills number leasing and delivery to you directly unless you arrange an Azure Marketplace private offer. References: Messaging Connect - https://learn.microsoft.com/azure/communication-services/concepts/sms/messaging-connect Relevant sections: Get a Phone Number with Messaging Connect; Required Payload Format Phone number management for United Kingdom - https://learn.microsoft.com/azure/communication-services/concepts/numbers/phone-number-management-for-united-kingdom Relevant sections: Number types and capabilities availability; Subscription eligibility

Answer accepted by question author

SHOUMIK CHAKRAVARTY 575

You haven't missed anything. There's no field for the Infobip API key because Azure doesn't store it. It goes in each send request instead. From the Messaging Connect docs:

"Microsoft doesn't retain any credentials used to access external Messaging Connect partners. Partner API keys are used only to process each message request and are immediately discarded after the request is complete."

That's why there's no setting for it in the portal.

The phone number is the real issue, and I think it comes down to how you bought it.. The flow is meant to start on the Azure side rather than at Infobip. You open your ACS resource, go to the Messaging Connect blade, pick Infobip, accept the terms, and Azure hands you off to Infobip to buy the number. Infobip provisions it, syncs it back, and it appears in your resource automatically.

Going straight to Infobip skips the part that ties your Infobip account to your ACS resource, which is almost certainly why nothing is showing. Before you buy a second number, walk through the blade and then ask Infobip support whether they can attach the one you already have. Their integration guide covers their side of it.

Two things worth knowing before you get much further.

It's still public preview, and the docs recommend against building production workloads on preview features. Worth factoring in for something you're planning to run as a service.

You'll also need the preview SDKs, and Python and Java aren't supported yet. .NET and JavaScript both have preview packages with MessagingConnect in them.

You also need the send-with-options overload rather than the plain send. The docs give this example:

smsClient.Send(
    from: "<YOUR-ACS-NUMBER>",
    to: ["<RECIPIENT-NUMBER>"],
    message: "Hello",
    options: new SmsSendOptions(true)
    {
        MessagingConnect = new MessagingConnectOptions("<YOUR-INFOBIP-API-KEY>", "infobip")
    });

Two smaller things. Provisioning isn't instant, and the timing is Infobip's rather than Microsoft's, so a delay doesn't necessarily mean something has gone wrong. When the number does appear it'll carry an Operator Name label, which is how you tell Messaging Connect numbers apart from ones provisioned directly by Azure.

And since you mentioned forwarding, make sure you're getting a Long Code (VLN). Alphanumeric sender IDs can only send, they can't receive.

Help make this community better for everyone: if this answer resolved your issue, please accept it or leave an upvote. If not, share more details in a comment so we can continue the discussion and find the right solution.

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Answer 1

For Infobip numbers, ACS does not import the number by manually entering the phone number or API key in the normal Phone numbers flow. The supported flow is Messaging Connect.

What is missing:

In the Azure portal, open the Azure Communication Services resource.
Go to the Messaging Connect blade.
Choose the partner, accept the terms, and complete number acquisition in the partner portal.
After Infobip provisions the number, the partner triggers the sync with Azure Communication Services.
Once that sync completes, the number appears automatically in the ACS resource and is ready to use with the ACS SMS API.

Key point: there is no separate step to manually “add” the Infobip number into ACS from the standard phone number screen.

About the Infobip API key:

The Infobip API key is used when sending SMS with a Messaging Connect number.
It is not described as a portal field for linking the number into ACS.
In Infobip, the documented steps are: sign in to the Infobip portal, create a new API key, enable sms:message:send, and save the key securely.

When sending with a Messaging Connect number, the API call must include the messagingConnect / MessagingConnect object with:

the Infobip API key
partner set to infobip

If that object is omitted, the request fails with a validation error.

So the practical path is:

Verify the number was acquired through the Messaging Connect partner flow from the ACS resource.
If the number was bought directly in Infobip outside that flow, wait for or confirm the partner sync into ACS from the partner side.
Use the Infobip API key only in the ACS SMS send request for Messaging Connect.

Messaging Connect