respond.io vs SleekFlow: Meta's Rates or a Lower Plan Price
By Joris van Huët
Enterprise Interim CMO & Marketing Leader · 15+ years · 50+ orgs
Published
2026-10-26
The short answer: if a team of up to ten answers WhatsApp, Instagram and calls and sends few campaigns, SleekFlow is the cheaper way into AI agents: its Pro plan costs $139 a month on monthly billing for 500 monthly active contacts and 10 user accounts (SleekFlow pricing). Once marketing templates run into the thousands, respond.io wins the message bill: its Growth plan is $199 a month for 1,000 active contacts with 10 users (respond.io pricing), and it adds nothing to Meta's rates, while SleekFlow charges $0.18366 per marketing message to a Dutch number where Meta's own card says $0.1597 (SleekFlow rate card, Meta pricing). All checked on 26 October 2026.
Disclosure: I may earn a commission through some links on this site. It does not change what this page says.
Price your own month first:
- Plan, number and messages together. For example, a month with 3,000 marketing templates to Dutch customers and 900 people in two-way chats. SleekFlow: $139 + $15 to host the WhatsApp number + 3,000 x $0.18366 = $704.98, plus four blocks of 100 extra contacts at a price its pricing page does not print (SleekFlow pricing). respond.io: $199 + 3,000 x $0.1597 = $678.10, with the 900 contacts inside Growth's 1,000 (respond.io pricing).
- The number your customers already use. SleekFlow counts a contact as active when you message them through the WhatsApp Business App on the same number, under Co-existence, so chats your staff keep answering on their phones still count (SleekFlow pricing FAQ).
- Last month's unique conversations. Neither tool counts people who only received a one-way broadcast. Count the customers who wrote to you or were written to individually last month; SleekFlow's own rule of thumb is that 20 unique chats a day come to about 450 a month.
The two plans that matter, side by side
| respond.io Growth | SleekFlow Pro | |
|---|---|---|
| Monthly billing | $199 | $139 |
| Billed yearly, per month | $159 | $109 |
| Active contacts included | 1,000 | 500 |
| Users | 10, then $20 each | 10 user accounts |
| Past the contact limit | $12 per 100, billed at the end of the cycle | 100 added at a time for that month, price not listed |
| WhatsApp messages | Meta's fees, nothing added | SleekFlow rate card, plus $15 a month per number |
| HubSpot | Included | From Premium, $349 |
| Trial | 7 days, Growth features, no card | 7 days of Pro, no card |
From the respond.io pricing page and billing help, and the SleekFlow pricing page with its FAQ. Below these, respond.io Starter is $99 for 5 users with unlimited contacts but no broadcasts, workflows or AI agents, and SleekFlow Essential is $69 for 3 seats and 500 contacts, without AI agents or broadcasts and still rolling out by country.
What separates them
Who sets the price of a message
This is the line that grows. respond.io's calculator FAQ says it does not charge additional fees on top of Meta's own (pricing calculator). SleekFlow lists its own table: from 1 October 2026, $0.18366 per marketing message, $0.05750 per utility message and $0.0500 per service message to Dutch numbers (SleekFlow rate card), against Meta's $0.1597, $0.05 and $0.05 on its USD card (Meta pricing). If your accounts run in euros, Meta's EUR card lists €0.1323 and €0.0414 for the same messages. A team that answers more than it broadcasts barely notices the gap.
Where the CRM sync starts
respond.io puts HubSpot, workflows and broadcasts on Growth, the plan most teams will buy anyway (pricing). SleekFlow keeps HubSpot and Zoho sync, webhooks and agents that act inside other systems for Premium at $349 a month, and gives Pro connections to Shopify, Google Sheets, Zapier, Make and Facebook Lead Ads (SleekFlow pricing). If HubSpot is your system of record, compare $199 with $349, not with $139.
How a person takes back a chat
Both expect a human behind the agent. respond.io lets a rep take a conversation over from the composer, and the how-to on qualifying leads with respond.io shows the routing. SleekFlow's version is newer and more explicit, below.
One AI step: the agent answers, a rep takes over with context
SleekFlow's Human-AI Conversation Control gives the inbox an AI handling folder that lists every conversation where an AgentFlow agent holds a live session, active or on standby. A rep filters it, replies to take over, and the agent goes quiet. Before handing back, the rep adds context, say "refund approved, do not offer a discount", so the agent's next answer starts from the facts a person just settled.
The human check is the folder itself: once a day someone reads the active sessions for anything involving money or a complaint and takes those over. Two conditions from the help page: an admin switches it on under Feature previews, and the workspace needs AgentFlow on its plan.
Test both before paying either
Both trials run seven days and take no card. Plan the week before you start it: one real campaign template, twenty real inbound chats and one handover each, then compare minutes per resolved chat.
Read SleekFlow's trial terms before inviting customers in. The trial runs on Pro, and if day seven passes without a subscription the workspace pauses, with no messages in or out, no automations and no API calls (SleekFlow pricing FAQ), so any customer you sent to that number during the test meets silence until someone pays.
If the harder question is who in the company owns WhatsApp at all, sales or support, that is a team decision before it is a tool decision, and it is the kind an interim CMO settles in the first month.
Choose respond.io if your job is
- Sending marketing templates at volume and paying Meta's rate with nothing on top.
- Running a sales team that syncs leads and stages with HubSpot without a premium tier.
- Talking to customers by phone and by chat, with one active-contact count covering both.
Choose SleekFlow if your job is
- Putting AI agents on a support or sales inbox for the lowest entry price.
- Keeping staff on the WhatsApp Business App while the team inbox runs alongside.
- Connecting Shopify and Google Sheets on a mid-tier plan, with deeper systems later.
For respond.io against a reach-first tool, see respond.io vs ManyChat.
FAQ
Does a broadcast recipient count as an active contact?
Not on either, unless they reply. respond.io's billing help excludes broadcasts from its count (billing help), and SleekFlow's FAQ excludes contacts who receive a one-way broadcast without replying or reacting (SleekFlow pricing).
Is SleekFlow's Essential plan available everywhere?
Not yet. The pricing page says Essential is rolling out by country and asks you to talk to sales for the right plan (SleekFlow pricing).
What does the AI cost on each?
On respond.io, AI usage is included on Growth and above under a fair-use policy, with on-demand credits at $15 per 1,000 if you exceed the allowance (pricing FAQ). SleekFlow lists AI agents as part of Pro and sells CX Intelligence, its conversation analysis, as an add-on from $99 a month (SleekFlow pricing).
ABOUT THE AUTHOR
I am Joris van Huët, an enterprise interim CMO. 15+ years, 50+ organizations, including ING, P&G, Nestlé, BNP Paribas, WeTransfer and Vinted. I take on innovation projects (venture building, design sprints), agentic marketing (setting up and running AI agents) and hands-on multi-channel work. See the track record.
I wrote and published this with AI assistance, and I answer for it. Claims about my own experience are limited to the track record above, and a statistic links to its source or is labelled as an example. I sell interim and fractional CMO work, which is why this site exists. How this site is written.
A senior operator doing the work: campaigns, channels, CRM and AI agents, live from day one.