# WhatsApp or SMS for collections: when to use each | Shimli > WhatsApp to negotiate and collect; SMS for those without data. How to combine them in one collections flow, with GSMA data and Shimli results. [Comparisons](https://www.shimliapp.com/en/comparar) Collections by channel ## WhatsApp or SMS for collections: both, in the right order. The short answer WhatsApp lets you converse, negotiate and collect in the same chat, and in Shimli it reaches a 98% open rate. SMS reaches phones without data or WhatsApp: in Latin America, 72% of people have a mobile line but only 65% use mobile internet. The best collections strategy uses both in one flow: WhatsApp first, SMS where WhatsApp doesn't reach. 5 min read · Updated October 6, 2026 Why choosing well matters 98% open rate of WhatsApp messages in Shimli operations Shimli production results +34% contact rate in early collections with Shimli agents Shimli results · 2025 72% / 65% of Latin America's population has their own mobile line, but only 65% use mobile internet: the gap is reached by SMS or call [GSMA, The Mobile Economy Latin America 2024 ↗](https://www.gsma.com/solutions-and-impact/connectivity-for-good/mobile-economy/latam-2024/) ### A collections flow with both channels This is how they combine in Shimli. Each customer gets the channel that reaches them, and whatever they reply comes back to the same case. - WhatsApp - SMS - AI agent - 01 WhatsApp Three days before the due date Reminder with an approved template and payment link to the whole portfolio on WhatsApp. - 02 SMS If the message isn't delivered An SMS goes to the same number, with a short link to the payment. - 03 AI agent The customer replies “I can't pay” The agent understands, checks the balance and offers an extension within your policy, on the channel where they replied. - 04 WhatsApp The promise is recorded Confirmation on WhatsApp and a reminder scheduled for the new date. - 05 SMS On the payment day A short SMS reminder for those who don't open WhatsApp. ### The comparison, point by point They don't compete: each reaches different customers. The table shows what each one is best at. | Criterion | WhatsApp official API | SMS text message | Both in Shimli one flow | | --- | --- | --- | --- | | Reach | Anyone with WhatsApp and data | Any phone, even without data | WhatsApp first and SMS where it doesn't reach | | Converse and negotiate | Yes, with text, buttons, documents and payment links | Short text replies | The agent negotiates on whichever channel the customer replies | | Open rate measured in Shimli | 98% in Shimli operations | No read confirmation | Delivery and reply measured on the same dashboard | | Cost per message | Meta's rate by category and country | The SMS provider's rate by country | Each message on the channel that makes sense | | Requirement for the customer | Having WhatsApp | Just a mobile line | Nothing extra | WhatsApp and SMS come out of the same Flow Builder in the $139 monthly plan. Messages are billed by Meta or the SMS provider at each country's rate. [See pricing](https://www.shimliapp.com/en/precios) ### When each one fits It isn't a contest: they're tools for different problems. #### Use WhatsApp to… - Converse, negotiate and collect in the same chat. - Send documents, receipts and payment links. #### Use SMS to… - Reach those without data or WhatsApp. - Short reminders when WhatsApp isn't delivered. #### Use both in Shimli to… - Cover the whole portfolio with one flow. - Have every reply come back to the same case and agent. ### Frequently asked questions What people ask when comparing. Why not use only WhatsApp? – Because not all your customers have it or have data. In Latin America, according to the GSMA, 72% of people have a mobile line but only 65% use mobile internet. SMS reaches that gap. Can the customer reply by SMS? + Yes. The agent understands the reply, records it on the case and continues on whichever channel the person has available. How much does each message cost? + It depends on the country and the channel. WhatsApp is billed by Meta according to the message category; SMS by the provider according to the country. You can estimate WhatsApp with the site's calculator. Sources - GSMA, “The Mobile Economy Latin America 2024” - Shimli, production operation results (98% WhatsApp open rate; +34% contact rate in collections, 2025) ### Create your first agent in under 10 minutes. Describe what you need to the assistant and watch the agent work. Or we book 30 minutes and look at it on your operation. [Create account](https://shimli.app/user/auth/create-account) Book a demo