Choose business messaging software by what the platform counts and what your team must do after a message arrives. respond.io and SleekFlow use monthly active contacts but gate workflow and integration depth differently. Trengo counts conversations within a seven-day window. Wati separates seat capacity, automation triggers, API limits and template-message charges. Interakt’s marketing and support packages advertise unlimited agents while excluding its dedicated Sales CRM roles. An unlimited-contacts or unlimited-messages label does not make channel traffic, automation and every kind of user free.
What the buying decision includes
This comparison concerns a shared operational inbox for WhatsApp and related customer channels, with campaigns, routing and human ownership. It is distinct from buying a raw SMS API, a website chat widget or a general ticketing system. Specify the required channels and numbers, who sends campaigns, who handles replies, and which CRM or order system needs updates. Count active contacts, repeat conversations, operators, automated actions and destination-country message traffic separately. A software subscription and a messaging network’s usage charges are different cost layers.
| Product | Buying rationale | Commercial or edition boundary | Resolve before purchase |
|---|---|---|---|
| respond.io | Contact-based inbox and workflow platform | Growth for workflows; Advanced for deeper controls | What counts as active and what AI policy applies? |
| SleekFlow | Omnichannel inbox with integrated AI agents | MACs, seats, channel hosting and advanced AI use | Which integrations and channel rollout are live? |
| Trengo | Team inbox with conversation allowances | Seven-day conversation unit; annual/monthly pools | How often does one customer start a new unit? |
| Wati | WhatsApp-centered automation and routing | Seat caps, triggers, API quotas and template fees | Which webhook and commerce scope is included? |
| Interakt | WhatsApp/Instagram marketing and support | Plan/channel limits; Sales CRM roles separate | Does unlimited agents cover your workflow? |
respond.io
respond.io’s USD annual-billed plans show Starter at $79 per month, Growth at $159 and Advanced at $279. Starter has five users; Growth and Advanced have ten at their base allowance. Growth introduces broadcasts, workflows and the developer API, while Advanced adds workflow HTTP requests, webhooks, multiple workspaces and SSO. Growth and Advanced start with 1,000 monthly active contacts. Meta’s WhatsApp charges are separate. respond.io official source.
Shortlist it when unique contacts are a useful commercial unit and the workflow tier matches your operation. A contact can count through either chat or calling activity. The page shows AI-credit allowances while its FAQ describes included AI usage subject to fair use, so confirm the applicable policy instead of assuming unlimited AI processing. Price the exact number of users, contacts and integrations together. The entry inbox and the package required for an HTTP-based order lookup are different purchases. respond.io official source.
SleekFlow
SleekFlow separates Essential, Pro, Premium and Enterprise. Pro adds AI agents, broadcasts and its automation builder; Premium adds API-connected AI actions, webhook/HTTP automation and stronger governance. Its current annual USD display starts Pro with 500 monthly active contacts and ten seats, while Premium starts with 1,000 contacts and ten seats. Extra contacts, seats, channel hosting and channel messages are separate cost dimensions. SleekFlow official source.
Prefer this shortlist when agent actions in commerce or CRM systems matter. Basic FAQ replies and advanced action-taking AI have different credit treatment. Its page describes automatic contact-capacity additions in blocks of 100 for the current billing month. Confirm which channels and the Essential rollout are available in your country: the navigation marks some capabilities as coming soon. An all-channel headline should not substitute for a deployment-specific availability and fee check. SleekFlow official source.
Trengo
Trengo defines a conversation around a reply to an inbound or outbound customer message within a seven-day window; replies outside that window start another conversation. Its current EUR display shows Boost at EUR 299 per month billed annually with ten users and 6,000 annual conversations. Monthly billing is EUR 349 with 500 conversations per month. Pro raises user and conversation allowances; added users, conversations, AI usage and broadcasting can add charges. Trengo official source.
This model fits a team that can forecast repeat conversation windows rather than unique contacts alone. One returning customer can use several conversation units, making a contact count from another provider an unsuitable denominator. Annual and monthly allowances should be compared on their actual renewal periods, not assumed to roll over identically. Confirm channel fees and the AI journey or action scope in the offer; the page labels AI Journeys as beta and warns that packaging may change. Trengo official source.
Wati
Wati’s retrieved regional pricing is in EUR and distinguishes Growth, Pro and Business. Growth includes three users with no additional-user option, 10,000 monthly API calls and no webhooks. Pro includes five users, additional seats for a fee, 200,000 API calls and limited webhooks. The plans separately meter included automation triggers and AI credits. Template messages carry additional charges by message type and destination. Wati official source.
Use Wati’s shortlist when WhatsApp-centered campaigns, team routing and commerce integrations match the operating model. A three-person team and a six-person team may need different tiers even before message volume changes. Confirm the precise webhook events, integration list and template rate card for your account region. Unlimited broadcasts at an upper tier does not mean unlimited free template delivery. Shopify integration and extra numbers are also priced additions, so include them in the comparable stack. Wati official source.
Interakt
Interakt’s retrieved US pricing route separates Marketing & Support Hub, AI Agents and Sales CRM. Growth and Advanced marketing/support packages list unlimited agents, but explicitly exclude dedicated Sales CRM roles with restricted contact visibility and CRM features. Growth lists a choice of WhatsApp or Instagram; Advanced includes both, branching chatbot flows, assignment and advanced webhooks. Template charges remain separate from the software subscription. Interakt official source.
Consider Interakt when this marketing/support scope and channel selection fit the team. Do not substitute unlimited ordinary inbox agents for the sales-role permissions your process needs. The retrieved page contains several product and billing views and even destination-specific rate examples, so obtain the exact region, billing cycle, channel combination and template markup in a written proposal. Unlimited stored contacts or messages describes capacity; it does not remove network charges or make every commercial module part of the package. Interakt official source.
Which purchase fits your operation?
Shortlist respond.io for contact-based workflow operations, SleekFlow for integrated agent actions, Trengo when seven-day conversation accounting suits your service pattern, Wati for WhatsApp-centered automation with explicit API tiers and Interakt for its defined marketing/support channel packages. Compare the same inbox-to-system action and human handoff. The cheapest subscription can change once repeated conversations, additional operators, automation triggers and network traffic enter the bill.
Prepare one purchasing worksheet with required channels and numbers, active contacts, repeat seven-day conversations, seats by role, automated actions and outbound templates by destination. Have each supplier mark included capacity, overage behavior and the action that requires an upgrade. Keep ownership of the WhatsApp Business account and number migration explicit. No platform can make a messaging network approve every template or guarantee delivery and conversion.
For related decisions, compare business SMS APIs and support helpdesk systems.
By Toolverly Editorial, with AI-assisted research and drafting. Product information checked November 5, 2026.
Photo by Petr Macháček on Unsplash. Read about our publication or send a correction.