WhatsApp Business API on AWS

What we set up

WhatsApp on AWS runs through AWS End User Messaging Social. Your WhatsApp Business Account (WABA) is linked to your AWS account, messages go out with SendWhatsAppMessage, and inbound messages and statuses arrive at an event destination you choose. It is part of what AWS calls Communication Developer Services.

FactualMinds has no published WhatsApp engagement. The facts on this page come from AWS documentation and our WhatsApp field guide, which links every source.

Architecture

AWS publishes two samples of this reply path: end-user-messaging-bedrock (WhatsApp to SNS, Lambda, and an optional Bedrock agent) and the two-way multi-channel chat sample (SMS and WhatsApp). Neither is a FactualMinds deployment.

One-time passcodes on WhatsApp

Since October 16, 2026, Notify can generate, send, and verify a passcode on WhatsApp from an AWS-managed template. That removes your own code store. Meta’s Authentication fee still applies on top of the AWS message fee.

WhatsApp in Amazon Connect

If live agents should take WhatsApp contacts, the same linked number can be imported into Amazon Connect. Customers write on WhatsApp, the contact flow routes them, and agents answer in the agent workspace with the rest of the contact history. Amazon Lex can take the first turn.

Engagement phases

1. Fit check. If the customer has never written to you on WhatsApp, a business-started thread needs a template and a Meta fee. For some jobs the RCS page is the better start.
2. Account and number. Link or migrate the WABA and confirm the origination number is ACTIVE. The public samples refuse to run without it.
3. Templates. Get one Utility template approved for order status before any model is connected.
4. Event path. Subscribe Lambda to the SNS topic and prove that a status event never reaches Bedrock.
5. Agent and handoff. Connect the Bedrock agent with read-only tools, set a session lifetime, and route money changes to a person or to Connect.
6. Cost reporting. Log AWS fees and Meta fees on separate lines.

What could go wrong

• Every status event hits the model. Delivery and read events share the topic with user messages. Filter first.
• Wrong template category. A Marketing template sent as a support reply is a different Meta meter and a different opt-in.
• Budget from the AWS fee alone. 10,000 outbound messages are $50 in AWS fees (29 September 2026 rate), plus whatever Meta’s row says for that country and type.
• Sessions that never expire. Using the phone number as the session id is fine only after you decide how long a session lives.

Who this is for

Good fit if:

• Your customers already message you on WhatsApp, or you serve countries where WhatsApp is the default way people contact businesses.
• You want WhatsApp sending, events, and billing to run in your AWS account next to your existing IAM, logging, and event pipeline.
• You have a clear job for the channel: order status, appointment reminders, support replies, or one-time passcodes.
• Someone on your side can approve company details with Meta and own the opt-in language.

Not a fit if:

• Your main goal is bulk promotions to people who have never messaged you. Marketing templates need opt-in and are subject to Meta rules that vary by country.
• You need a hosted inbox with no AWS involvement. This is a developer service, and the agent workspace is Amazon Connect or something you build.
• You cannot take your number out of the WhatsApp or WhatsApp Business app, since a number in use there must be deleted first.
• You operate from China, where AWS does not offer the service.

Approach and architecture

1. Account link. In the End User Messaging Social console you link a business account and complete Meta’s sign-up flow. You can create a new WABA, migrate an existing one, or add a phone number to an existing one. You give AWS access to the WABA and allow it to bill you for messages.
2. Phone number registration. The number must receive an SMS or voice passcode during sign-up. If you import a WABA, you need the PIN for each number on it.
3. Templates. One Utility template for order status or the job you start with, an Authentication template if you send codes, and Marketing templates only where you hold opt-in. Meta reviews templates, and approval status shows in the console.
4. Sending. Inside the 24-hour customer service window, all message types can be sent. Outside it, only approved templates to users who opted in. The window starts or refreshes each time the customer messages you. We code this branch once and test it.
5. Inbound and status events. Turn on a message and event destination for the number, point it at an Amazon SNS topic, and subscribe a function. Delivery, read, and fail statuses share that stream with user messages, so the function filters them. A recipient who is not on WhatsApp produces an event with a status of fail.
6. Reply path. Either the Bedrock agent described above, or an Amazon Connect queue for live agents. For follow-ups with attachments or long content, hand off to Amazon SES.

Deliverables and engagement boundaries

We deliver:

• A fit check and a written number plan: which number, which jobs, which countries
• The account link or migration, walked through with your Meta admin
• Template drafts per job, with category and variable mapping, submitted for your approval
• The SNS event path, status filter, alarms, and a test that proves a read receipt never reaches a model
• The window-versus-template send logic in your codebase or as a reference module
• A cost sheet with the AWS fee and the Meta fee on separate lines
• Handover and a runbook for template rejections and quality-rating drops

You or third parties own:

• The Meta Business Account, the WABA, and compliance with WhatsApp’s terms and messaging policy. Meta can prohibit your use of the service at any time.
• Meta’s template decisions, quality ratings, and per-country pricing
• Opt-in capture and records
• Message content and the production application
• Support staffing if you route to live agents

Prerequisites, limits, and restrictions

• A Meta Business Account (can be created during sign-up) and a number that can receive an OTP by SMS or voice.
• A number already in the WhatsApp Messenger or WhatsApp Business app must be deleted from it first.
• Imported WABAs need the PIN for every number.
• Not available to customers located in China.
• Regional availability for End User Messaging Social expanded during 2026. We confirm your Region against the AWS page before design.
• Templates are the only message type allowed outside the 24-hour window, and only to users who opted in.
• AWS rates are on the pricing page, and Meta’s are set by Meta. We do not state Meta rates here.
• AWS also documents newer WhatsApp features such as Flows and calling. We scope them only when a job needs them, and they are not part of the starting engagement.

Related guides and services

• WhatsApp field guide
• Communication Developer Services decision hub
• SMS and 10DLC guide
• RCS guide
• AWS Communication Developer Services consulting
• RCS Business Messaging on AWS
• Amazon SES consulting
• Amazon Connect

Next step

Tell us whether you have a WABA today, which countries you serve, and which jobs WhatsApp should handle. Contact us.