What is the difference between a linked device and the WhatsApp Business API?

A linked device is a companion session on a normal WhatsApp or WhatsApp Business app account: up to four devices, working even while the phone is offline, as long as the account reconnects on the primary phone at least every 14 days. The Business Platform (API) is a separate Meta product for programmatic messaging at scale, accessed through the Cloud API or a Meta solution partner, with template categories and per-message pricing. They are different products with different rules.

Is automating WhatsApp through a linked device allowed?

WhatsApp’s help content prohibits unauthorized automated or bulk messaging on the consumer and Business apps and says accounts showing spam-like automated behaviour can be restricted or banned, with machine-learning detection. The Business Platform is the sanctioned route for automation. Any tool automating through a linked-device session, ours included, operates outside that sanctioned route and carries restriction risk that no vendor can honestly promise away.

Which transport does Conversa use today?

Linked-device transport, stated plainly on our features page. It keeps onboarding fast and keeps the agency on its existing number, and Conversa is designed to behave like a human-paced conversation layer rather than a broadcaster: it only ever messages buyers who already enquired, with paced follow-ups and warm-up protections. That reduces the risk profile; it does not eliminate it, and we say so rather than promise otherwise.

When should an agency insist on the official API?

When compliance or procurement requires the sanctioned route, when volumes go beyond conversational scale, when you need template campaigns (which only exist on the API), or when the number must never depend on a phone reconnecting every 14 days. The trade: BSP onboarding, template approval, per-message fees for templates, and replies inside the 24-hour service window being the free part.

Linked device vs WhatsApp Business API for real estate

TL;DR

There are exactly two ways software can sit on an agency’s WhatsApp: a linked-device session on a normal WhatsApp/Business-app account, or the WhatsApp Business Platform (API), Meta’s product for programmatic messaging.
Linked devices: up to four companions, they keep working while the phone is offline, and the account must reconnect on the primary phone at least every 14 days (official). The free Business app’s built-in automation stops at greeting, away and quick-reply messages (official).
WhatsApp’s help content prohibits unauthorized automated or bulk messaging on the apps and describes ML-based restriction of accounts that behave like spammers (official). The API is the sanctioned automation route (official).
Conversa runs on linked-device transport today, deliberately conversational and enquiry-only. That choice has real advantages and a real risk profile; both are below, and pretending otherwise is how this industry earns its reputation.

Transport one: the linked-device session

Multi-device is an official WhatsApp feature: link up to four companion devices (Web, desktop, tablets, a second phone) to one account, and they keep receiving and sending “without the need to keep your primary phone connected”, provided you “log in to WhatsApp on your primary phone every 14 days” or linked devices are disconnected (About linked devices; the Business-app variant works the same). The account stays a normal consumer or Business-app account: your number, your chats, no Meta onboarding.

What the free Business app officially automates is short: greeting messages for first contact, away messages for off hours, and up to 50 quick replies (greeting, away, quick replies). No AI, no CRM logic, no per-listing behaviour. Anything smarter riding on this transport comes from third-party software driving a linked session, which is where the policy question begins.

Transport two: the WhatsApp Business Platform (API)

The Business Platform is Meta’s separate product to “programmatically message and call on WhatsApp” at scale, accessed via the Cloud API or a Meta solution partner (overview, partners). Since 1 July 2025 it is priced per delivered template message by category and country: marketing templates are always charged, utility and authentication templates are free inside an open service window, and “all non-template messages are free” inside the 24-hour customer-service window a user’s message opens (official pricing; EUR rate cards are downloadable there). The old “1,000 free conversations a month” tier is history: it belongs to the deprecated conversation-based model, replaced in July 2025.

For a real-estate reply workflow, one detail matters enormously: replying to a buyer who wrote to you is the free part of the API. Template fees exist chiefly for business-initiated and marketing messages.

What the policy actually says

WhatsApp’s help centre is explicit: do not “bulk message, auto-message, or auto-dial” using WhatsApp or the Business app; unauthorized automated or bulk messaging violates the Terms of Service, and WhatsApp uses “machine learning technology and reports from users” to restrict or ban accounts that behave that way (unauthorized automated or bulk messaging, restricted accounts). Note the precision: the policy targets unauthorized automation on the apps. Automation as such is not banned; the Business Platform is its authorized home.

The honest conclusion, which most vendor pages in this category avoid writing: any tool that automates through a linked-device session, Conversa included, operates outside WhatsApp’s sanctioned automation route and carries a restriction risk no vendor can promise away. If a vendor tells you a linked-device bot is “fully compliant”, they are describing their hopes.

The honest trade-off table

Linked device, for it: onboarding in hours on your existing number; no template approval process; no per-message Meta fees; full conversation history stays in your app.
Linked device, against it: outside the sanctioned automation route with ML-based restriction risk; tethered to a phone that must reconnect every 14 days; one account rather than a platform contract; scale is conversational, not campaign.
API, for it: the authorized route; no phone tether; scale and templates; free service-window replies.
API, against it: partner onboarding and template review; per-message fees for business-initiated messages; the number lives inside Meta’s business platform with its own rules.

How Conversa holds this risk today

We state the transport on the features page and here: linked device. The design keeps the risk profile as low as that choice allows: Conversa only ever messages buyers who already enquired about a property (when the enquiry arrives from a portal by email, it sends that buyer the first WhatsApp; it never cold-contacts anyone), follow-ups are paced like a person, new numbers go through warm-up protection, and volume stays conversational because qualification is the product, not broadcasting. Reduced is not eliminated: an agency that needs zero transport risk, or whose procurement requires the sanctioned route, should demand the API and we will say so to their face. The rest of what we do and do not claim lives on the evidence page.

Questions to ask any vendor, including us

Which transport is this, exactly: a linked-device session or the Business Platform? (If the answer is vague, it is a linked device.)
If linked device: what happens to my conversations when the session drops or the account is restricted? What pacing and volume protections exist?
If API: which solution partner, which template categories will I pay for, and what does the EUR rate card say for Spain?
Either way: who owns the number, and how do I leave with my history?

Then test the actual behaviour: the public demo shows how Conversa converses; this article is the transport disclosure to read next to it. For the money side, our cost comparison covers the human alternative.

Linked device vs WhatsApp Business API: the honest transport guide for real-estate agencies