You've decided the WhatsApp Business API is the right tool for your solar EPC. You've heard it costs "a few paise per message." Then your first BSP invoice arrives, and the number is not what you expected.
WhatsApp API pricing in India is genuinely confusing because the cost has two completely separate layers: Meta's own per-message fee and the BSP's platform fee on top. Most Indian BSP sales pages show only the platform fee. Most YouTube explainers show only the Meta fee. Neither tells you the full picture for a solar business operating at realistic lead volumes.
This guide gives you the complete breakdown: Meta's INR per-message rates (effective 1 October 2026), illustrative platform fees for five providers, cost modelling for a solar EPC at 200, 500, and 1,000 chats per month, and an illustrative ROI calculation to test against your own numbers.
Key takeaway
For an Indian solar EPC that mostly replies to inbound WhatsApp enquiries, Meta's message charges are small (₹0.115 per service or utility message and ₹0.8631 per marketing message, per Meta's India rate card effective 1 October 2026) and the provider's monthly platform fee is the bigger cost. Meta has charged per delivered message since 1 July 2025, not per conversation, so older guides that quote per-conversation rates describe a model Meta replaced. A marketing message costs about 7.5 times a utility or service message, so broadcasts are where the bill can run up.
How Meta bills for WhatsApp: the per-message model explained
Since 1 July 2025 Meta charges per message, and only for messages it delivers. Messages from a customer to your business are not charged. A 24-hour customer service window opens when the customer messages you and resets each time they message again, and you can only send non-template messages while it is open. The rules are on Meta's developer platform (checked 31 Oct 2026).
The per-message rates are low, so the arithmetic is simple. A solar lead negotiation might involve 15–25 messages over two days, of which perhaps 10 are your replies. At the service rate, that is at most 10 × ₹0.115 = ₹1.15, and nothing at all while you are inside your free 1,000 service messages for the month.
Meta prices each message by category: service, utility, authentication or marketing. The category depends on the kind of message and why you are sending it:
| Category | Who initiates? | Example for solar EPC | India rate per delivered message (from 1 Oct 2026) |
|---|---|---|---|
| Service | Your reply while the 24-hour window is open | Answering "5 kW solar ka rate kya hai?" in the chat | ₹0.115 (first 1,000 a month free) |
| Utility | Business sends transactional message | Appointment confirmation or payment receipt for an existing order | ₹0.115 |
| Authentication | Business sends OTP/login code | Sending a one-time password for customer portal login | ₹0.115 (₹2.4971 international) |
| Marketing | Business sends promotional message | Broadcast: "Diwali solar offer, 10% off this week" | ₹0.8631 |
Why this matters for solar EPCs specifically. Most Indian solar leads are inbound, the customer sends the first message after seeing your Google ad, Facebook campaign, or Google My Business listing. That first customer message opens a 24-hour window in which your replies are service messages, at ₹0.115 each after the first 1,000 free each month. Only outbound template campaigns (festive offers, bulk re-engagement) fall into the expensive marketing category at ₹0.8631 each.
The free tier, 1,000 service messages per month
Meta gives every business phone number a free tier of 1,000 service messages per month, and charges from the 1,001st (as of 1 October 2026, per Meta's official WhatsApp pricing documentation, checked 31 Oct 2026). Unused messages do not roll over.
Do the sum on your own chats. If you send 10 replies in each chat, 1,000 free service messages cover 100 chats a month, and 100 more chats cost about ₹115. For a small solar EPC, the Meta service charge is small either way, and the BSP platform fee is the main cost.
The free tier covers service messages only. Every marketing message you send costs ₹0.8631 from the first one.
Watch out. The 1,000 free service messages are counted per month, and unused ones do not roll over. Additionally, this free tier is at the Meta level only. Your BSP charges their platform fee regardless of how many conversations you have.
The free-entry-point exception, click-to-WhatsApp ads
This is one of the most significant cost advantages for solar EPCs running Facebook or Google ads: Messages inside a Click-to-WhatsApp (CTWA) free entry point window are not charged, and Meta's pages disagree on whether that window lasts 72 hours or up to 7 days.
When a customer clicks a Facebook or Instagram ad that opens a WhatsApp chat (our click-to-WhatsApp ads setup guide covers Meta's current free-window rules), (on the WhatsApp Android or iOS app, not desktop or web) a customer service window opens. If you respond within it, that reply opens a "free entry point" window in which Meta does not charge for marketing, utility, authentication or service messages. Meta's developer documentation says this window may stay open for up to 7 days, while its WhatsApp Business platform pricing page says 72 hours. Plan for 72 hours and treat any extra days as a bonus until your billing confirms them. Meta Business Agent messages (its AI agent) remain charged.
For a solar EPC running Facebook lead ads to WhatsApp (a strategy covered in detail in our solar Facebook ads guide), this can remove most Meta message charges for ad-sourced leads while the window is open. You still pay your BSP platform fee and your ad spend, and charges resume once the window closes. If you haven't set up the API yet, our step-by-step WhatsApp Business API setup guide walks through registration, BSP selection, and template approval from scratch.
| Lead source | Meta message cost | Notes |
|---|---|---|
| Facebook/Instagram click-to-WhatsApp ad | Free while the window is open (72 hrs to 7 days) | Needs a reply within 24 hours; check your billing |
| Customer messages directly, you reply (service messages) | Free (first 1,000 a month) | After 1,000: ₹0.115 per message |
| Business-initiated utility template (appointment confirmation) | ₹0.115 | Charged per delivered message, unless inside a free entry point window |
| Outbound marketing broadcast | ₹0.8631 | No free tier applies; highest per-message cost |
BSP platform fees, what you actually pay each month
The BSP's platform fee is the fixed monthly cost you pay regardless of your message volume. This covers the dashboard, chatbot builder, agent seats, template management, analytics, and support. For a fuller breakdown of what a BSP actually does and how the underlying API works, see our WhatsApp Business API definition and BSP mechanics glossary entry.
Here is an illustrative comparison of five providers. We have not re-verified these plan prices for this update, so confirm each one on the provider's own pricing page before you budget:
| BSP | Starter Plan | Growth Plan | Agent Seats Included | Chatbot Flows |
|---|---|---|---|---|
| AiSensy | ₹999/month | ₹2,499/month | 2 | Basic |
| Interakt | ₹2,756/month | ₹4,347/month | 3 | Good |
| Wati | ₹3,999/month | ₹7,999/month | 5 | Good |
| Gupshup | ₹4,000/month | Custom | Varies | Advanced |
| Twilio India | Pay-as-you-go | No plans | Unlimited | DIY only |
Important: BSP prices above are platform fees only and exclude Meta's per-message charges. The BSP collects Meta's charges separately (usually monthly, based on your actual message volume) and bills them to you at Meta's rate or, with some providers, with a markup.
BSP markup on Meta rates. Some BSPs pass through Meta's rates at cost. Others may add a markup on per-message charges. Before signing a BSP contract, ask specifically: "Do you pass through Meta's official India message rates, or do you add a markup?" Meta publishes its official per-message rates here.
Real monthly cost for a solar EPC, three volume scenarios
Let's model the all-in cost for three different solar EPC sizes. Every input is an illustrative assumption, and all figures exclude GST. The model assumes:
- You send 10 service replies in each chat, and one marketing template to 20% of chats
- Provider plan: Interakt starter (₹2,756/month) for the smallest, Wati starter (₹3,999/month) for the middle, Wati growth (₹7,999/month) for the largest
- Meta rates from 1 October 2026: ₹0.115 per service message after the first 1,000 free each month, ₹0.8631 per marketing message
| EPC Profile | Chats per month | Meta Fee | BSP Fee | Total / Month | Cost per chat |
|---|---|---|---|---|---|
| Solo installer / small EPC | 200 | ~₹150 | ₹2,756 | ~₹2,906 | ~₹14.5 |
| Mid-size EPC (5–10 reps) | 500 | ~₹550 | ₹3,999 | ~₹4,545 | ~₹9.1 |
| Large EPC (10+ reps, active campaigns) | 1,000 | ~₹1,210 | ₹7,999 | ~₹9,209 | ~₹9.2 |
Meta fee calculation for 500 chats: 5,000 service messages, of which 1,000 are free, so 4,000 × ₹0.115 = ₹460, plus 100 marketing templates × ₹0.8631 = about ₹86, which is about ₹546, rounded to ₹550. For 200 chats: 1,000 chargeable service messages (₹115) plus 40 marketing templates (about ₹35) is about ₹150. For 1,000 chats: 9,000 chargeable service messages (₹1,035) plus 200 marketing templates (about ₹173) is about ₹1,210.
The counterintuitive finding. On these assumptions, a solar EPC at 200 chats a month pays more per chat (about ₹14.5) than one at 500 a month (about ₹9.1) because the provider's platform fee is a fixed cost that gets spread over more chats. The unit cost improves as your lead volume grows, then levels off once you move to a bigger plan.
The 24-hour service window, how it affects your solar sales process
The 24-hour service window is one of the most important mechanics to understand in WhatsApp API pricing, and it directly changes how your sales reps should behave.
When a customer messages your business, a 24-hour customer service window opens. Within those 24 hours, you can send free-form text, images, PDFs, voice notes and links without using a pre-approved template. Those replies are service messages: free for the first 1,000 a month, then ₹0.115 each. Your rep can have a completely natural conversation.
After 24 hours of customer inactivity, the window closes. If you want to message that customer again, you must use a pre-approved template message, which Meta charges by its category (₹0.115 utility, ₹0.8631 marketing).
For solar sales, this creates one critical workflow rule: always reply to customer messages within 24 hours, even if only to say "we'll send your proposal by tomorrow morning." Keeping the service window open means your rep can send the proposal, answer follow-up questions, and handle objections, all in free-form conversation. See our walkthrough of sending a branded proposal PDF on WhatsApp for the exact steps to attach and send a proposal without breaking the service window. To keep that window open without relying on memory, set reminders on each lead with Quickest's WhatsApp follow-up.
Practical rule for your team. Set a hard SLA of "reply within 4 business hours to any customer WhatsApp message." This single rule keeps service windows open, so your reps can reply without templates. Our solar follow-up cadence guide covers what to send after that.
How to reduce your WhatsApp API costs
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1
Route all paid ads to click-to-WhatsApp
Shift your Facebook and Instagram ad destination from a landing page to a WhatsApp number. While a free entry point window is open (plan for 72 hours), Meta does not charge for marketing, utility, authentication or service messages. Illustrative example: if you would otherwise send one marketing template to each of 200 chats, that is 200 × ₹0.8631 = about ₹173 in Meta fees avoided.
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2
Maximise your service window, reply fast
Every time a customer messages your business, you get 24 hours of free-form conversation. Fast replies (under 4 hours) mean you rarely need to re-initiate contact with a template. Slow replies mean the window closes and you must use a template, and a marketing template costs ₹0.8631.
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3
Limit outbound marketing broadcasts to high-value segments
Marketing messages cost ₹0.8631 each, about 7.5 times a service message. Only broadcast to your highest-intent segments: leads who have received a proposal but haven't responded in 7+ days, or past customers for referral asks and seasonal promotions. Sending a broadcast to 500 cold contacts costs about ₹432 in Meta fees alone, and low open rates mean poor ROI. Quality over quantity. Before you build a broadcast list, review our WhatsApp broadcast rules for solar to avoid template rejections and account flags.
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4
Negotiate your BSP contract annually, not monthly
Some providers offer a discount for annual prepayment, so ask. Lock in an annual plan only once you've validated the platform works for your team, and do a 2-month trial first to confirm fit before committing.
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5
Use your CRM to give each lead one owner
Without a clear owner for each lead, multiple reps may message the same lead twice, creating duplicate charges and confusing the customer. Every duplicate template message wastes ₹0.115 to ₹0.8631. Assigning each lead to one rep in your CRM avoids this.
Pros and cons grid: WhatsApp API pricing model for solar
Advantages
- 1,000 free service messages a month cover small volumes
- Click-to-WhatsApp free entry point window removes Meta message charges while it is open
- Service and utility messages are priced low (₹0.115 each)
- Replies to inbound leads are service messages, at the lowest rate
- Cost per chat drops as the fixed platform fee spreads over more chats
Disadvantages
- Fixed BSP platform fee applies even at zero message volume
- Marketing messages cost about 7.5× a service message, easy to overspend on broadcasts
- BSP markup on Meta rates may be opaque, must ask directly
- The four-category system is confusing, and the template category you choose sets the charge
- Meta rates can change, always check Meta's official pricing page for current rates
ROI calculation for a solar EPC at realistic volumes
Let's model the ROI for a mid-size solar EPC in India: 8 reps, 400 WhatsApp leads/month, averaging 4 kW residential systems. Every input below is an assumption for illustration, not a measured benchmark, so replace them with your own numbers.
Monthly WhatsApp API cost:
- BSP (Wati starter): ₹3,999
- Meta fees (400 chats, assuming 10 service replies each, so 4,000 messages, of which 1,000 are free: 3,000 × ₹0.115): ~₹345
- Total: ~₹4,350/month
Revenue impact:
- Pre-API: assume rep response time averages 90 minutes and 35% of leads are gone by the time of first reply
- Post-API: assume a chatbot replies within 30 seconds and lead loss drops to 15%
- Leads recovered: 400 × 20% = 80 additional leads engaged per month
- Assume 8% of those convert to site visits: 6.4 additional site visits/month
- Assume a 40% site visit-to-close rate
- Additional closes per month: 2.5
- Assume an average margin of ₹35,000 per 4 kW residential system
- Additional monthly revenue: 2.5 × ₹35,000 = ₹87,500
ROI on these assumptions: ₹87,500 additional margin on about ₹4,350 spend = about 20× return. At one-tenth of that (₹8,750) it would still cover the cost, but every input is an assumption, so run it again with your own numbers.
What drives the ROI isn't the chatbot itself, it's speed to first response. The WhatsApp API enables 30-second auto-replies that may recover leads who would otherwise get impatient and call your competitor. If your reps already reply within 15 minutes, the incremental ROI of the API narrows significantly. Audit your current first-response time before assuming you need the API.
Stats summary: WhatsApp API in India 2026
₹0.115
Per service message after the first 1,000 free each month (India, from 1 Oct 2026)
1,000
Free service messages every month per business number
72 hrs
Free entry point window after a click-to-WhatsApp ad chat (Meta's developer docs say up to 7 days)
7.5×
Cost of a marketing message (₹0.8631) vs a service message (₹0.115)
5
Providers compared in this guide: AiSensy, Interakt, Wati, Gupshup, Twilio
~20×
Illustrative ROI on assumed inputs for a 400-lead EPC, not a promise
When does it make sense to skip the API entirely?
Not every solar EPC should be on the WhatsApp Business API. There's a viable alternative for businesses under a certain volume threshold.
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Under 50 WhatsApp leads/month: The BSP platform fee alone (minimum ₹1,000–2,756/month) exceeds the value of what you're automating. Share proposals from your phone on the WhatsApp Business app and use Quickest Solar CRM for follow-up reminders and saved message templates instead. There is no provider contract, and you send each message yourself. We did not find a per-message rate card for the Business app, so check Meta's current terms.
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50–150 WhatsApp leads/month: Evaluate the API if you have a rep coverage gap (multiple reps sharing one number or missing after-hours messages). Below that threshold, a disciplined CRM follow-up system covers the gap more cheaply. Read our guide on when to buy a solar CRM to assess your readiness for API-level tooling.
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150+ WhatsApp leads/month: The API may be justified. The free tier covers part of your service messages, a click-to-WhatsApp free entry point window covers ad-sourced leads while it is open, and the BSP platform fee is spread across more leads. Run the cost model above with your own volumes.
For a detailed comparison of the chatbot approach vs the simpler follow-up automation approach, see our WhatsApp chatbot for solar business guide. For understanding how WhatsApp fits into your overall sales funnel, the solar sales funnel India guide gives the full pipeline context. And if you're evaluating digital marketing channels alongside WhatsApp, the digital marketing for solar businesses guide covers the full channel mix.
Additional context for your WhatsApp API decision:
- WhatsApp marketing for solar installers, templates and tactics
- Solar marketing strategy India, full channel plan
- Solar lead from Facebook ads, connecting ads to WhatsApp
- WhatsApp templates for solar follow-up, approved formats
Frequently asked questions
Want to put this into practice?
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