Whatsable vs Kapso vs Zernio: agency phone numbers compared

If you run WhatsApp for multiple clients or brands, the number of connected phone numbers you can attach to one account determines whether you need one seat or ten. Whatsable Agency, Kapso, and Zernio all let you connect multiple WhatsApp Business API numbers, but they pack and price those connections differently. This comparison uses public pricing checked 6 Oct 2026 for Kapso and Zernio, plus Whatsable Agency product-locked phone packing, so you can see included numbers, overage, and how the meters differ.

Agency phone packing

Platform	Base plan	Included numbers	Overage per number
Whatsable Agency	Agency (contact-tier, e.g. $53.90/mo at 500 contacts)	100	$5/mo
Kapso Platform	$299/mo	50	$5/mo
Kapso Pro	$25/mo	3	$10/mo
Kapso Free	$0/mo	1	Extra-number price not listed publicly on Free; Pro adds 3 then $10/mo each
Zernio	Usage-based	1–2 free; 3–10 at $6 each; 11–100 at $3 each; 101–2000 at $1 each; 2001+ at $1 each	Graduated bands, no hard cap

Whatsable Agency includes up to 100 connected phone numbers. Each additional connected phone number is $5.

Kapso's Platform plan ($299/mo) includes 50 connected phone numbers, then $5/month each. The Pro plan ($25/mo) includes 3 connected phone numbers, then $10/month each. The Free plan includes 1 connected phone number (extra-number price on Free not listed publicly; Pro and Platform publish overage).

Zernio charges per connected account. Each WhatsApp number counts as one connected account. The first 1–2 accounts are free, accounts 3–10 cost $6 each per month, accounts 11–100 cost $3 each, accounts 101–2000 cost $1 each, and accounts beyond 2001 remain $1 each with no published cap.

How each meter works

The three platforms bill on different meters, which makes direct cost comparison difficult without knowing your message volume and contact base.

Whatsable bills on unique contacts (the number of distinct phone numbers you message in a rolling 30-day window) plus connected phone numbers. Agency contact-tier pricing (for example $53.90/mo at 500 unique contacts) is separate from the $5 per extra connected number. Whatsable Pro starts at $49/mo for 500 unique contacts with $12 per 100 contacts overage (monthly USD). The inbox includes Chat Handoff and Coexistence features that let human agents and automation share the same number.

Kapso bills on platform message allowance (inbound plus outbound) plus connected phone numbers. Meta message fees are separate; you pay them through Kapso at cost with no markup, or directly to Meta. Kapso markets a developer WhatsApp Cloud API wrapper with sandbox, CLI, Project MCP, workflows, AI agents, and team inbox surfaces. The platform plan message allowance covers messages sent and received on the numbers you connect.

Zernio bills per connected account (each WhatsApp number is one account) plus outbound message volume. The first 10,000 outbound messages per month are free; after that, Zernio charges $0.0001 per message. Meta template and call fees are billed by Meta directly to your WhatsApp Business Account; Zernio states publicly that it never marks up or re-bills Meta fees. Zernio is a multi-platform API (WhatsApp, SMS, voice, email), so the connected-account model applies across channels. If you provision a dedicated number through Zernio, that costs from $3/mo for US numbers and $3 to $30/mo depending on country. If you bring your own number via Embedded Signup, there is no Zernio number fee.

Worked examples: packing cost at scale

These examples show the cost of connecting phone numbers only (monthly USD). They do not include contact-tier fees (Whatsable), message allowances (Kapso), outbound message fees (Zernio), or Meta message fees (all three).

3 connected numbers:

• Whatsable Agency: 100 included, so 3 numbers = $0 connected-number overage; contact-tier separate
• Kapso Pro: 3 included at $25/mo base = $25/mo total
• Zernio: 1–2 free, third number $6 = $6/mo for the third account

10 connected numbers:

• Whatsable Agency: 100 included = $0 connected-number overage; contact-tier separate
• Kapso Pro: 3 included + 7 extra at $10 each = $25 + $70 = $95/mo
• Zernio: 1–2 free + accounts 3–10 at $6 each = 0 + (8 × $6) = $48/mo

50 connected numbers:

• Whatsable Agency: 100 included = $0 connected-number overage; contact-tier separate
• Kapso Platform: 50 included at $299/mo base = $299/mo total
• Zernio: 1–2 free + 8 at $6 + 40 at $3 = 0 + $48 + $120 = $168/mo

100 connected numbers:

• Whatsable Agency: 100 included = $0 connected-number overage; contact-tier separate
• Kapso Platform: 50 included + 50 extra at $5 each = $299 + $250 = $549/mo
• Zernio: 1–2 free + 8 at $6 + 90 at $3 = 0 + $48 + $270 = $318/mo

150 connected numbers:

• Whatsable Agency: 100 included + 50 extra at $5 each = $250 connected-number overage; contact-tier separate
• Kapso Platform: 50 included + 100 extra at $5 each = $299 + $500 = $799/mo
• Zernio: 1–2 free + 8 at $6 + 90 at $3 + 50 at $1 = 0 + $48 + $270 + $50 = $368/mo

200 connected numbers:

• Whatsable Agency: 100 included + 100 extra at $5 each = $500 connected-number overage; contact-tier separate
• Kapso Platform: 50 included + 150 extra at $5 each = $299 + $750 = $1,049/mo
• Zernio: 1–2 free + 8 at $6 + 90 at $3 + 100 at $1 = 0 + $48 + $270 + $100 = $418/mo

At 100 numbers or fewer, Whatsable Agency includes all connections with no overage. Zernio's graduated bands make it cheaper than Kapso Platform for mid-range packing (10–100 numbers), but you still pay per account. Kapso's $5 overage on Platform matches Whatsable's $5 overage above 100, but Kapso's base is $299/mo for 50 numbers versus Whatsable's 100 included.

Product shape: inbox vs MCP vs API

Beyond number packing, the three platforms serve different use cases.

Whatsable is a shared inbox built for teams that need human agents and automation on the same WhatsApp number. Chat Handoff lets you route conversations between bots and people without breaking context. Coexistence means multiple agents can see and reply to the same conversation thread. Whatsable bills on unique contacts, so if you send 10,000 messages to 200 people, you pay for 200 contacts, not 10,000 messages.

Kapso is a developer-facing WhatsApp Cloud API wrapper: Project MCP, CLI, workflows, AI agents, and inbox surfaces (app, standalone inbox, or embedded). The message-allowance model fits teams that think in API message volume rather than unique WhatsApp contacts. Public Make.com and Zapier.com app directories did not list Kapso when Whatsable last checked those directories on https://whatsable.app/compare/whatsable-vs-kapso; Kapso documents an official n8n node plus webhooks and MCP.

Zernio is a developer-first API that connects WhatsApp, SMS, voice, and email through one endpoint. The connected-account model and per-message pricing suit agencies that build custom integrations or resell messaging to clients. Zernio's public claim (see also https://whatsable.app/compare/whatsable-vs-zernio) is zero markup on Meta fees, and the first 10,000 outbound messages per month are free, which reduces cost for moderate-volume accounts.

When to pick which

Pick Whatsable Agency if:

• You manage up to 100 WhatsApp numbers under one roof and want them all included.
• You need a shared inbox where human agents and automation coexist on the same number.
• You prefer billing by unique contacts rather than message volume.
• You want Chat Handoff to route conversations between bots and people without losing thread context.

Pick Kapso if:

• You run high-volume broadcast campaigns and need message-allowance pricing.
• You want Project MCP, CLI, workflows, and an embedded or standalone inbox inside a developer platform.
• You have fewer than 50 numbers and the $299/mo Platform plan fits your budget, or you start small with Pro (3 numbers at $25/mo).
• You prefer to pay Meta fees through the platform at cost rather than managing separate Meta billing.

Pick Zernio if:

• You connect more than 100 WhatsApp numbers and want the lowest per-account cost (graduated bands down to $1/mo per number above 100).
• You build custom integrations and prefer API-first architecture over a pre-built inbox or workflow UI.
• You send moderate outbound volume (under 10,000 messages/mo free, then $0.0001/msg).
• You want to provision dedicated numbers in multiple countries ($3 to $30/mo depending on region) or bring your own via Embedded Signup with no number fee.

FAQ

How many phone numbers can I connect on Whatsable Agency?

Whatsable Agency includes up to 100 connected phone numbers. Each additional connected phone number is $5.

Does Kapso charge extra for Meta message fees?

Meta message fees are separate from Kapso's platform pricing. You pay them through Kapso at cost with no markup, or you can pay Meta directly. Kapso's plans cover the platform message allowance (inbound plus outbound) and connected phone numbers.

How does Zernio count connected accounts for WhatsApp?

Each WhatsApp number you connect counts as one connected account. The first 1–2 accounts are free, accounts 3–10 cost $6 each per month, accounts 11–100 cost $3 each, accounts 101–2000 cost $1 each, and accounts beyond 2001 remain $1 each. If you provision a dedicated number through Zernio, that adds a number fee ($3/mo US, $3 to $30/mo by country). If you bring your own number via Embedded Signup, there is no Zernio number fee.

What is the difference between unique-contact billing and message-allowance billing?

Unique-contact billing (Whatsable) charges based on the number of distinct phone numbers you message in a rolling 30-day window. If you send 100 messages to 10 people, you pay for 10 contacts. Message-allowance billing (Kapso) charges based on total inbound plus outbound messages, regardless of how many unique recipients. If you send 100 messages to 10 people, you consume 100 messages from your allowance.

Can I bring my own WhatsApp Business API number to all three platforms?

Yes. Whatsable, Kapso, and Zernio all document paths to connect a WhatsApp Business number (Embedded Signup / Coexistence or dedicated API-only, depending on the product). Zernio also offers dedicated number provisioning (from $3/mo US, $3 to $30/mo by country) if you buy a number through Zernio; own-number Embedded Signup has no Zernio number fee. Kapso public pricing lists free pre-verified US numbers on Free and Pro as setup helpers; connected numbers are the ones that send and receive with customers. Whatsable connects your own number via Embedded Signup as a Meta Tech Provider.

Which platform has the lowest cost for 200 connected WhatsApp numbers?

At 200 numbers, Zernio costs 1–2 free + 8 at $6 + 90 at $3 + 100 at $1 = $0 + $48 + $270 + $100 = $418/mo for connected accounts (plus outbound message fees after 10,000/mo and Meta message fees). Whatsable Agency costs $500 connected-number overage (100 included + 100 extra at $5 each); contact-tier separate. Kapso Platform costs 50 included + 150 extra at $5 each = $299 + $750 = $1,049/mo (plus message allowance and Meta fees). Zernio's graduated bands make it the lowest per-account cost above 100 numbers, but total cost depends on message volume and contact base.

Sources

All pricing and feature details checked October 6, 2026.

• Whatsable Agency connected phone numbers (live Agency card on https://whatsable.app/pricing, checked 2026-10-06): Whatsable Agency includes up to 100 connected phone numbers. Each additional connected phone number is $5. Agency contact-tier pricing (for example $53.90/mo at 500 unique contacts) is separate from the $5 per extra connected number.
• Whatsable Pro pricing: https://whatsable.app/pricing ($49/mo for 500 unique contacts, $12 per 100 contacts overage)
• Kapso pricing: https://kapso.com/pricing (Free $0/mo 1 number; Pro $25/mo 3 numbers then $10 each; Platform $299/mo 50 numbers then $5 each; Meta fees separate at cost or direct)
• Zernio connected accounts: https://docs.zernio.com/pricing (1–2 free; 3–10 $6 each; 11–100 $3 each; 101–2000 $1 each; 2001+ $1 each)
• Zernio WhatsApp pricing: https://docs.zernio.com/platforms/whatsapp/pricing (dedicated numbers from $3/mo US, $3 to $30/mo by country; own number via Embedded Signup no number fee; outbound messages first 10,000/mo free then $0.0001/msg; Meta fees billed by Meta, Zernio no markup)