HubSpot WhatsApp: Native Channel vs Marketplace App vs Custom Build

WhatsApp keeps creeping up the agenda for UK B2B teams on HubSpot. Buyers expect to message you the way they message everyone else, and sales and service want those conversations attached to the right contact record rather than trapped on someone's phone. The question is rarely whether to support WhatsApp. It is which route to take: HubSpot's native channel, a certified marketplace app, or a custom build on the Custom Channels API.

This is a decision-stage guide, not a setup tutorial. We will lay out what each option actually gives you, where each one stops, and how to choose without painting yourself into a corner. The right answer depends on your volume, your number pool, the routing logic you need, and how cleanly any third party maps to your CRM data model.

Option 1: HubSpot's native WhatsApp channel

HubSpot can connect WhatsApp directly into the conversations inbox and Help Desk. This requires Marketing Hub or Service Hub at Professional or Enterprise tier (the exact hub and tier depend on your portal, so check before you commit). You connect a WhatsApp Business account (not a personal one, which is Meta's rule), and you need admin access to the company's Meta Business Manager along with the business phone number you want to send from.

The native channel is the cleanest path because there is no engineering involved. A few details shape whether it fits:

• Business verification gate. An unverified Meta Business Manager is capped at 50 business-initiated conversations per day. Verified accounts go beyond that.
• Number capacity. Each WhatsApp Business account can have up to 25 phone numbers associated with it.
• Template message ceiling. HubSpot applies a cap of 1,000 template messages per month, shared across all connected WhatsApp business accounts, resetting on your subscription start date. For B2B conversational volumes this rarely bites; for high-volume outbound it can.
• The 24-hour window. A session stays open for 24 hours after the customer's last reply. Outside that window you must send an approved template message to re-initiate, which is Meta's customer service window rule surfaced inside HubSpot.
• Inbox exclusivity. Once connected to HubSpot, messages no longer appear in the WhatsApp mobile or web app. They live only in the HubSpot inbox.
• No historical sync. Only new messages after connection sync across. Prior conversation history does not migrate.

Native fits when you have one or a handful of business numbers, conversations are handled by people or bots inside HubSpot, and your outbound template volume sits comfortably under the cap. You accept the inbox-exclusivity trade-off and Meta's template and window rules in exchange for zero build cost.

A note on consent

HubSpot collects WhatsApp consent two ways: a keyword opt-in, where the contact sends a standalone keyword such as START (the message must contain only the keyword, so "Can I START?" will not trigger it), or a manual opt-in by an admin where the contact has given explicit, verifiable consent. There are two subscription types, WhatsApp Marketing and WhatsApp Transactional. Worth flagging: this messaging consent is a different system from HubSpot's website cookie banner and Google Consent Mode, which govern tracking, not WhatsApp. Do not conflate the two. Treat all of this as background rather than legal advice, and sign off your consent approach with your own legal team before you go live.

Option 2: A certified marketplace app

When native limits start to bite, a certified WhatsApp app from the HubSpot App Marketplace is the middle option. These come from messaging vendors and business solution providers, and they tend to add richer campaign tooling, broadcast features, multi-number handling and analytics that the native channel does not offer.

It helps to know what "certified" actually means, because it is a real quality signal. To certify, an app needs a minimum of 60 active installs (raised from six in May 2024), must have been listed in the Marketplace for at least six months, and now recertifies every two years. HubSpot's Ecosystem Quality team assesses apps on security, privacy, reliability, performance, usability, accessibility and value, responding within 10 business days and completing review within 60. From 31 March 2026, listing submissions need demo videos rather than test credentials, and legacy CRM cards are being retired in favour of app cards.

A marketplace app fits when a vendor already solves your shape: they hold the business solution provider relationship, they offer the campaign and broadcast tooling you want, and you are comfortable with their pricing and data model. The caveat we always raise: certification confirms the app is secure and reliable, but it does not guarantee the app maps cleanly to your CRM model. If your associations, custom objects or routing logic do not fit the vendor's assumptions, you inherit a gap you cannot close.

Option 3: A custom build on the Custom Channels API

HubSpot's Custom Channels API went generally available in April 2025 and lets you bring any text-based, two-way messaging channel into the conversations inbox and Help Desk. It requires Sales or Service Hub at Professional or above. WhatsApp, SMS, Instagram, Telegram, LINE and others are all candidates, which means the same engineering pattern serves more than one channel.

A few constraints shape the build decision:

• Public app only. The Custom Channels API cannot be used with a private app. You build and maintain a public app with an OAuth 2.0 install flow.
• Threading. You can supply your own thread identifiers or opt into HubSpot-managed threading, which mirrors the native WhatsApp and SMS behaviour and auto-reopens threads closed under 24 hours.
• Webhooks. You receive a webhook when an admin connects a channel, publish incoming messages in, and receive webhooks for outgoing messages to deliver on the end channel.
• Rich content. Per HubSpot's implementation guide, formatting is limited to bold, italic and hyperlinks, with image attachments capped at three files of 2 MB each in PNG or JPEG. Confirm these against the live reference before building to them, as they came from an implementation blog rather than the core API docs.

A custom build fits when you need WhatsApp inside HubSpot on your own terms: your own Meta or business solution provider relationship and number pool, your own template-volume economics by going direct to a provider rather than living under HubSpot's shared cap, routing and automation logic the native channel does not offer, or a channel HubSpot does not support natively at all. This is the Default to Build lane. When the native cap or a marketplace app's data model forces a compromise the business genuinely cannot accept, owning the integration is the answer. You can read more about what you can build with custom HubSpot development if you are weighing the broader case.

How to choose

Start with native. If your numbers, volume and routing fit inside it, you are done, and you have spent nothing on engineering. If a vendor app already solves your exact shape and maps cleanly to your CRM, take that and accept the dependency. Reach for a custom build when the cap, the data model or an unsupported channel forces a trade-off you cannot live with, or when WhatsApp is one of several channels you want to consolidate into one inbox with shared logic. As a rough guide on cost, a custom Conversations channel build starts from £12,000, which is a useful frame against the recurring cost of a vendor app that almost fits.

If you are unsure which side of those lines you fall on, that is exactly the conversation to have before anyone touches a configuration screen.

Where SpotDev fits

SpotDev is the software engineering firm for HubSpot customers: a UK HubSpot Diamond Partner with an in-house engineering team, HubSpot Custom Integration Accredited and Cyber Essentials Plus certified. We build custom Conversations channels and other engineered HubSpot work, and everything we deliver comes with our guarantee: delivered on time, or you get 20% back. If WhatsApp is part of a wider messaging or integration picture, our integrations work and our HubSpot development team cover the full build, from OAuth and webhooks to the CRM data model underneath. To scope your options, request a quote and we will tell you honestly whether native, an app or a build is the right call.

Frequently asked questions

Does HubSpot have a native WhatsApp integration?

Yes. HubSpot can connect a WhatsApp Business account directly into the conversations inbox and Help Desk, which requires Marketing Hub or Service Hub at Professional or Enterprise tier. You need admin access to your Meta Business Manager and the business phone number you want to send from. The native channel is the cleanest path because it needs no engineering, though you accept HubSpot's monthly template cap, the inbox-exclusivity trade-off and Meta's session window rules.

What are the limits of HubSpot's native WhatsApp channel?

Key limits include a cap of 1,000 template messages per month shared across all connected WhatsApp business accounts, a 50 business-initiated conversation per day limit until your Meta Business Manager is verified, and up to 25 phone numbers per WhatsApp Business account. Once connected, messages appear only in HubSpot and no longer in the WhatsApp app, and prior conversation history does not migrate across.

When should I build a custom WhatsApp integration instead of using native or an app?

Build a custom integration on HubSpot's Custom Channels API when you need WhatsApp inside HubSpot on your own terms: your own Meta or business solution provider relationship and number pool, your own template-volume economics to bypass HubSpot's shared cap, routing logic native does not offer, or a channel HubSpot does not support at all. It requires Sales or Service Hub at Professional or above and a public app with OAuth and webhook delivery.

What is the HubSpot Custom Channels API?

The Custom Channels API, generally available since April 2025, lets you bring any text-based, two-way messaging channel into the HubSpot conversations inbox and Help Desk, including WhatsApp, SMS, Instagram and others. It requires a public app (private apps are not supported), uses an OAuth 2.0 install flow, and offers either your own thread identifiers or HubSpot-managed threading that mirrors native behaviour.

Is a certified WhatsApp marketplace app a safe choice?

Certification is a genuine quality signal: certified apps are reviewed for security, privacy, reliability, performance, usability, accessibility and value, need at least 60 active installs and six months listed, and recertify every two years. However, certification does not guarantee the app maps cleanly to your CRM data model. If your associations, custom objects or routing do not fit the vendor's assumptions, you inherit a gap, so check the fit before committing.