How messaging platforms differ on price, seats and channels (2026)
Choosing a messaging platform is mostly a pricing-model decision. The channels look alike on a feature list; the invoices do not. This guide sets out the four differences that move the bill most, how the main providers approach each, and when a broader platform is simply the better buy.
Based on each vendor’s public pricing and documentation as we understood it in September 2026. Vendors change plans often, so check current terms before you decide.
The four differences that change your bill
1. Markup on message cost. For WhatsApp, Meta publishes a per-message rate by category and recipient country. Some providers pass it through unchanged and charge a platform fee; others add a percentage or sell credit bundles that make the per-message uplift hard to see. The useful question is always the same: what is your markup, as a percentage, over Meta’s published rate for my category and country?
2. How you pay for people. Support headcount grows with your success. Platforms that price agent seats separately tax exactly that growth; platforms that include seats move the cost back to message volume and the platform fee.
3. How contacts are billed. Some marketing suites bill on contacts stored, so a large but quiet list costs the same as an active one. Others bill only on what you send.
4. Currency and invoicing. USD-first billing is a monthly reconciliation chore for an Indian finance team that needs an INR invoice with GST and a ledger they can check against Meta’s rate card.
Side by side
| sendlz | Twilio / Sinch | MSG91 / Klaviyo | |
|---|---|---|---|
| WhatsApp per-message markup | None — Meta rate at cost | Markup over Meta rate, or enterprise-negotiated | Bundled credits, or via a partner |
| Agent seats | Unlimited, included | Priced per seat | Tiered or per seat |
| Contacts stored | Unlimited | Not applicable | Klaviyo bills per contact |
| Email backbone | Amazon SES on your own identity | Vendor-hosted (SendGrid, Mailjet) | Vendor-hosted |
| INR invoice with GST | Standard | Usually USD or EUR first | MSG91 yes; Klaviyo USD first |
| Contract | Monthly, cancel anytime | Pay-as-you-go or annual commitment | Annual discounts typical |
| Channels | WhatsApp, SMS, email | SMS, voice, verify, video, RCS, email | SMS, voice, WhatsApp, email, push |
When a broader platform is the right call
We run three channels well rather than eight adequately, and that is a real trade-off.
- You need voice, RCS or verify APIs in one contract. Twilio and Sinch are built for that breadth and carrier footprint.
- You want one Indian vendor across SMS, voice and WhatsApp. MSG91 consolidates those under one login with INR billing and local support.
- You live inside a full e-commerce marketing suite. Klaviyo’s Shopify reporting is deep, and its per-contact billing is the price of that suite.
When a focused platform is the better fit
If WhatsApp, SMS and email are where your revenue happens, you are paying for breadth you may not use. A flat platform fee with message costs passed through, seats included and a rupee invoice removes the three line items that grow fastest with your business.
A five-minute test for any vendor
- Ask for the markup over Meta’s published rate for your category and country, as a percentage.
- Ask what happens to the bill when you add ten support agents.
- Ask whether contacts you never message still count towards the invoice.
- Ask for a sample INR invoice with GST.
- Ask what leaving costs: notice period, number ownership and data export.
For the vendor-by-vendor detail, see our comparison pages for Twilio, Sinch, MSG91 and Klaviyo, or the full provider matrix.