Where do the channels differ?
The three channels differ on four points: how many people you reach, how quickly it gets read, what it costs and how personal it feels. Your choice depends on which customer data you hold and how your customers normally contact you.
| Criterion | SMS | ||
|---|---|---|---|
| Reach | Only app users | Any mobile number | Any email address |
| Speed of reading | Minutes | Minutes | Hours to days |
| Cost per message | Free or low | A few cents | Close to zero |
| Tone | Personal conversation | Short and businesslike | Formal |
| Follow-up | Visible in the thread | New message | New email |
In Flanders a large majority of adults use WhatsApp, but the share varies sharply with an older customer base. Look at your own customers before you fix a channel.
When does WhatsApp win?
WhatsApp wins when you know the customer personally and have chatted before: salons, dentists, contractors, coaches and garages with regulars. The message lands in the same thread as the appointment confirmation, which raises trust.
- The customer sees your name and your earlier messages, so it does not feel like advertising.
- You can follow up in the same thread, without a message from an unknown number.
- You can see whether the message was read, which helps you decide on a reminder.
When does SMS win?
SMS wins with one-off customers, with older audiences and anywhere you only hold a mobile number. No app is needed, the message lands on any handset, and it is nearly always seen within a few minutes.
The downsides are price and space. An SMS costs a few cents each and has to fit inside roughly 160 characters, link included. That is why your business name goes first and one sentence is all the room you get.
Typical winners: garages, medical practices, taxi firms, veterinary clinics and businesses with plenty of one-off customers.
When should you pick email?
Pick email when you want to reach hundreds of past customers at once, or when addresses are all you hold. It produces fewer reviews per message sent than WhatsApp, but it costs almost nothing, so the total can still come out higher.
Send plain text without styling, put the request in the first two sentences, and use a subject line that mentions the duration. Spread a large list across two weeks.
Templates for all three channels are in the article on asking customers for reviews.
What may you send, and to whom?
Write only to people who genuinely were customers, using the number or address they gave you for that job. Put a way to stop into every message, and record anyone who says they want nothing further.
- No bought or scraped lists, on any channel.
- One request and one reminder per job, then it stops.
- A clear opt-out, including on SMS and WhatsApp.
- Process customer data under the GDPR, with a retention period and a processing agreement.
The rules on what you may promise or ask inside the message are in the article on collecting reviews within the rules. Where your own situation is unclear, legal advice is the safe route.
How do you choose in practice?
Pick one main channel based on which detail you hold for most customers, then test for two weeks. Compare the number of reviews per hundred messages sent, rather than how the exercise felt.
- 1Count how many mobile numbers and how many email addresses you hold across your last hundred customers.
- 2Take the channel you have most data for as your main one.
- 3Run it for two weeks and record messages sent and reviews gained.
- 4Then test the second channel the same way and keep the winner.
In ReviewsPro you pick the channel per customer, and afterwards you see which channel produces the most reviews for your business.
Frequently asked questions
- Does WhatsApp produce more reviews than SMS?
- With customers you know personally and have chatted with before, usually yes. With one-off customers or older audiences, SMS often produces more, because no app is required and the message lands on any handset.
- What does an SMS review request cost?
- Expect a few cents per message through a business sender. At ten new customers a week that stays under a few euros a month, which is negligible against the value of a review.
- May I contact my customers on WhatsApp about a review?
- Yes, when they gave you their number as part of the service and you give them an easy way to stop. Do not send bulk messages to people who were never customers.
- How many messages may I send per customer?
- One request and one reminder. Anyone who ignores two messages will ignore five, and the risk of complaints climbs faster than the number of reviews.
- Can I combine several channels?
- Yes, and it is worth doing. Use WhatsApp or SMS as your main channel for customers whose number you hold, email for the rest, and a QR code at the counter for anyone you cannot reach digitally.