How many SMS from a campaign reach a phone that still rings? That question comes before every benefit of SMS marketing; the SMS marketing pillar explains how the channel works. The rates usually quoted (97% read, 5 to 15% click) are published by vendors without stating the base of calculation (sent or delivered), while Arcep, the French telecoms regulator, reports for late 2025 a SIM card churn rate of 4.0% per quarter on postpaid and 29.5% on prepaid (some of those numbers live on with another carrier). Each benefit below therefore carries its measure and its source, plus the condition that makes it true: a base of active numbers, then a compliant send.
Read and click rates: vendor figures, to be read with their denominator
1. Read within 4 minutes, with no read receipt
The smsmode white paper (2022), picked up by Klaviyo, puts the SMS read rate at 97% and the average delay at 4 minutes. The 98% figure that circulates elsewhere is credited sometimes to Gartner, sometimes to the Mobile Marketing Association; we found no primary study behind it that anyone can consult. The SMS protocol provides a delivery report and no read report (3GPP TS 23.040 specification), so the read rate is inferred from clicks and replies. The speed is solid. The percentage only means something if you know which messages it is computed on.
2. Email-level clicks, more frequent orders
SMS campaigns average a 5.76% click rate worldwide at Klaviyo (2025), within a 5 to 15% range, while email averages 5.3% in France according to DMA France. The click rate gap is thin. Klaviyo does claim an order conversion rate 2 to 5 times higher than a standard email, a vendor figure to read as such. The channel-by-channel detail is in SMS marketing vs email.
| Indicator | SMS | |
|---|---|---|
| Read or open rate | 97% (smsmode, 2022) | 18.22% (DMA France) |
| Average click rate | 5.76% (Klaviyo, 2025, worldwide) | 5.3% (DMA France) |
| Average unsubscribe rate | 0.16% (smsmode, 2024) | 0.22% (DMA France) |
The first row compares two measures of different kinds: an email open rate relies on a tracking pixel, an SMS read rate on deduction.
Reach and cost: 84.9 million SIM cards, 1.8 million of them dormant
3. A reach that follows the SIM card
84.9 million SIM cards (excluding M2M) were in service in France on 31 December 2025, a penetration rate of 123.7% (Arcep). SMS runs over the mobile network with no internet connection; 15.26 billion push SMS were sent in 2025, up 7.51% year on year according to the barometer of af2m, the French mobile multimedia association, published in February 2026. One definitional detail remains. The base is 97.9% active; the remaining cards, about 1.8 million (84.894 minus 83.068 million), are, under the definition of the active base used by Arcep, prepaid cards with no call, SMS or data for 3 months. In the last quarter of 2025, 1.656 million numbers also changed carrier. They can still be reached. The network on which the numbers in your customer file were first issued is not necessarily the right one anymore.
4. A cost counted per delivered SMS
The price of a credit depends on volume; the price grids are detailed in the article on low-cost SMS. The bill reads differently, though: with providers that charge per send, an SMS sent to an out-of-service number uses up a credit without ever ringing. On 20,000 sends, every percentage point of invalid numbers wastes 200 credits. A campaign’s ROI divides attributed revenue by credits consumed; wasted credits inflate the denominator. Billing mode is therefore one of the criteria in the guide to choosing an SMS provider.
Use cases: from appointment reminders to flash sales
5. Mostly transactional use
An appointment reminder the day before, a delivery code: these service SMS accounted for 9 billion messages out of 15.26 in 2025, or 59.2%, against 6.2 billion promotional ones (40.8%), again according to af2m. By sector, retail accounts for 31% of sends and banking and insurance 19%. Appointment reminders and booking confirmations fall into this service-message category.
In e-commerce, an abandoned-cart message reaches an identified customer while purchase intent is hot. The CNIL, France’s data protection authority, nonetheless rules out the “existing customer” exception when no sale has taken place, including with an account created online: by deduction, an abandoned-cart SMS sent to that profile requires consent collected separately. A flash sale, for its part, is promotional, with its consent and time-of-day rules (see below); examples of campaigns that work show the format.
6. Segmentation that feeds loyalty
Segmenting by date of last purchase or average basket decides who gets which message; personalization by first name and a tailored offer extends that logic, with a recognizable sender name. The 2026 af2m charter caps it at 11 alphanumeric characters, with clear brand identification and a ban on fields that look like a phone number. Segmenting a base full of dead numbers amounts to personalizing messages that have no recipient.
7. A complement to email, with RCS as a relay
A detailed email buried in a crowded inbox, then an SMS reminder when the offer is about to end: the two channels cover the same journey, and a short link in the SMS measures the click. RCS is coming up behind. The af2m counts 52 million compatible smartphones in France (84% of the installed base) and 738 active brands in 2025, up 75% in a year, with a single opt-in valid for both SMS and RCS since the 2026 charter. The use cases of RCS messaging and the business SMS offer extend this point.
Number base: the multiplier these 7 benefits assume
The calculation fits on one line: real click rate = clicks ÷ delivered SMS. On 20,000 sends including 1,000 to out-of-service numbers, 950 clicks give 5.0% of delivered and 4.75% of sent; the gap widens with the age of the base. An HLR Lookup queries carriers in real time, tells you whether a number is active and flags out-of-service or unknown numbers; CaptainVerify’s also returns the current carrier and the portability status. A phone that is merely switched off is not the same as a cancelled number. An out-of-service number plays the role of a hard bounce in email: the send cannot succeed. Filtering after the send does not refund the credits, already consumed with providers that bill per send; this list hygiene happens before. HLR says nothing about consent, which is proven elsewhere. Before each campaign:
- Extract the mobile numbers concerned and remove duplicates.
- Run the extract through HLR Lookup.
- Discard out-of-service lines and keep active ones, including those that changed carrier.
- Send, then calculate click, STOP and conversion rates on delivered SMS.
The only way to know whether your base still holds up is to run a sample through HLR Lookup before the next campaign. Carrier filters then play their part, detailed in SMS deliverability.
Legal framework: what the law sets, what the charter sets
In France, no promotional SMS goes out without the recipient’s prior consent, with one exception: the customer who has already bought a similar product or service (article L34-5 of the Postal and Electronic Communications Code, on Légifrance). The CNIL requires consent that is valid under the GDPR (freely given, specific, informed, unambiguous), so a dedicated box that is not pre-ticked; accepting the terms and conditions is not enough. The GDPR defines consent in Article 4(11) and guarantees the right to object in Article 21. In B2B, the right to object replaces prior consent. Each send must name the advertiser and offer a simple way to refuse, at no cost other than the transmission itself. GDPR in email marketing follows the same logic of proof.
Penalties exist: the CNIL fined a data broker 900,000 euros by a decision of 15 May 2025, notably for consents that were invalid and impossible to prove.
The second tier is professional. Breaches of the 2026 Business Messaging charter of af2m can lead to message delivery being cut off, which makes it a concrete constraint for any sender.
“To address issues of trust and the fight against fraud” (Alexis Trichet, president of af2m, February 2026, our translation)
| Rule | Origin | Content |
|---|---|---|
| STOP mention | af2m 2026 charter | STOP keyword, unsubscribe URL or RCS button; never paid |
| Promotional hours | af2m 2026 charter | 8am to 9:30pm; Monday to Saturday recommended; Sundays and public holidays tolerated but not recommended (charter in force since 1 March 2026) |
| Functional messages | af2m 2026 charter | Delivery, authentication: no time restriction |
| Sender name | af2m 2026 charter | 11 characters maximum, alphanumeric, identifiable brand |
The STOP mention has its own guide: SMS and the STOP law. Article L34-5 sets no numeric cap on send frequency; the unsubscribe rate (0.16% on average at smsmode, 2024) works as a thermometer.
Frequently asked questions
Does a transactional SMS require consent?
The CNIL treats messages needed to perform a contract or a requested service separately: they fall outside the prospecting regime. As soon as an offer is added, the promotional purpose returns, and consent with it.
Can you send a marketing SMS to a business phone number?
Yes, under the right-to-object regime. The CNIL recommends offering an opt-out box that is unticked by default; refusal must remain possible at every send.
What should you do with a contact who replies STOP?
Remove the number from the list before the next send. The af2m charter asks for handling as quickly as possible and rules out any unsubscribe that is paid or conditioned on a burdensome process. Keeping a record of the request proves it was honored.
Limits: what 160 characters cannot carry
An SMS holds 160 characters in the GSM alphabet and 70 as soon as a single character outside that alphabet (an emoji or an accented vowel such as â, ê, î, ô, û) forces UCS-2 encoding (3GPP TS 23.038); beyond that, the message is split into segments of 153 or 67 characters (concatenation, TS 23.040). The article on emojis in professional SMS details this trade-off. SMS carries neither image nor button, opt-in narrows the audience to those who said yes, and carriers filter suspicious traffic. The benchmarks in this article come from platform vendors and trade associations: their order of magnitude can guide a budget, their decimal proves nothing.
An SMS only counts once it has arrived.
