Klaviyo SMS marketing in France: setup and operating guide

Short answer. Klaviyo currently supports SMS to French numbers using a branded sender ID, with SMS but not MMS in its published availability table. Collect SMS-specific consent, identify the brand, provide a working unsubscribe method, and enforce France-aware quiet hours. Use SMS for a small number of genuinely timely customer moments, then measure incremental net value and opt-out, not clicks alone.

SMS is a high-attention channel. The same immediacy that creates value can also create complaints, carrier filtering, and loss of trust. International brands entering France should not reuse a US program, disclosure, sending number, or timing rule.

This guide was reviewed July 16, 2026 against Klaviyo's current SMS availability by country, SMS consent guidance, compliance basics, and the French data protection authority's electronic communication guidance. It is operational information, not legal advice. Have the program reviewed for the markets and products in scope.

Confirm current France support

Klaviyo's published availability table currently lists:

• France as a supported SMS country;
• country code +33;
• branded sender ID as the available sender type;
• SMS availability;
• no MMS availability for France.

Toll-free numbers, long codes, and short codes (vanity and non-vanity) are all marked unavailable on the France row. There is no French number to provision, so no number-based launch delay to plan for. France is also not among the three countries that currently require pre-registration of a branded sender ID: those are Australia, Ireland, and Spain.

Product support, registration, rates, and number types can change. Confirm them inside the account and with Klaviyo before buying a plan or promising a launch date.

A branded sender ID identifies the sender using brand text and cannot receive inbound messages. Klaviyo states that compliance keywords are not available for branded sender IDs for exactly that reason, and France is absent from its list of countries supporting two-way keyword messaging. So a reply of STOP is never processed in France, and the unsubscribe experience must not be built around it.

What Klaviyo does instead: it automatically adds an unsubscribe link to messages sent from a branded sender ID, and that link cannot be turned off. Keyword unsubscribe instructions remain available only for toll-free numbers, long codes, and short codes. Budget for the link: Klaviyo puts it at roughly 31 to 34 characters by default, which counts against the message segment.

Because the sender cannot receive a text, the classic double opt-in confirmation message is skipped automatically in branded sender ID countries. Klaviyo's documented alternative is Smart Opt-in, a one-time code the visitor re-enters on site, which requires a paid plan.

The branded sender ID itself must be 3 to 11 standard characters, contain at least one letter, and carry no special characters or punctuation.

Define the purpose of the French SMS program

Good SMS use cases share three qualities:

1. the information is time-sensitive;
2. the customer can act easily on a phone;
3. email or another channel would be materially slower or less useful.

Examples:

• limited restock requested by the subscriber;
• real delivery or order update under the correct message purpose;
• appointment or reservation reminder;
• subscription renewal or failure when properly configured;
• event starting soon;
• genuinely time-bound loyalty access;
• urgent customer-requested account information.

Weak uses:

• every routine newsletter;
• long educational content;
• generic product catalog;
• repeated discount reminders;
• campaigns sent because credits remain;
• sensitive information in an exposed lock-screen preview.

Create a channel charter that states allowed purposes, maximum ordinary frequency, quiet hours, approval owner, excluded product categories, and incident process.

Collect SMS-specific consent

Klaviyo's platform guidance requires a person to explicitly agree to SMS, separate from email or general marketing. It also requires SMS to be enabled and an active sender in the relevant country before platform consent collection.

For a French consumer marketing program, the CNIL states that promotional email and SMS generally rely on prior consent, with defined exceptions that require careful qualification. A conservative Klaviyo implementation should collect clear SMS-specific evidence rather than infer permission from checkout, an email subscription, or a customer account.

At collection, make clear:

• identity of the brand;
• that the choice is for SMS;
• purposes or types of messages;
• expected frequency where appropriate;
• any cost information required for the market;
• how to opt out;
• link to privacy information;
• whether data is shared with another controller.

Use a separate, unchecked choice. Do not make SMS consent a condition of purchase. Do not import purchased, affiliate, or shared lead lists as consent.

Retain:

• phone number in normalized international format;
• consent status;
• source and form version;
• timestamp;
• disclosure version;
• market;
• method, including confirmation where used;
• withdrawal or suppression history.

Localize the collection experience

Use French for a French-language customer journey unless there is a clear reason otherwise. The form, confirmation, welcome message, unsubscribe page, privacy information, and support path should agree.

Possible collection surfaces:

• separate SMS step after email signup;
• checkout checkbox;
• account or preference center;
• email invitation to join SMS;
• QR code or in-store form;
• loyalty enrollment;
• Customer Hub where current plan and configuration support it.

If one form collects email and SMS, show two distinct decisions. Do not hide the SMS disclosure behind a generic Continue button.

Klaviyo currently supports separate promotional, transactional, and Shopify order-update consent states in relevant configurations. Platform labels do not replace legal qualification. Decide the actual purpose of each message and verify the current implementation.

Configure the sender and brand identity

Choose France as the relevant sending country or add the current supported configuration. Verify:

• sender ID approval or activation;
• exact displayed brand;
• destination support;
• unsubscribe path;
• link domain;
• account and billing country;
• test-number availability;
• character encoding and message segments;
• prohibited or restricted content.

Keep the brand recognizable in every message even when the sender ID is visible. Sender display can vary by device, network, and forwarding context.

Use a branded link domain where supported and trustworthy HTTPS destinations. Avoid public link shorteners that can look suspicious or be filtered.

Enforce quiet hours and local time

Klaviyo's current compliance guide lists France quiet hours as:

• before 8:00 a.m.;
• after 10:00 p.m.;
• all Sundays;
• public holidays.

It notes that French carriers enforce these windows and may filter messages. Treat these as platform and carrier operating constraints, then verify whether a stricter internal policy or legal interpretation applies.

Schedule by the recipient's local time and confirmed market. A profile locale is not proof of current physical location, but the French phone country and customer context can inform routing. Do not default unknown time zones into a risky send window.

Transactional urgency does not justify casual exceptions. Define which necessary operational messages can send, how the platform treats them, and what legal or carrier rules apply.

Design the SMS content

An effective SMS usually contains:

• recognizable brand;
• one customer reason;
• one action;
• essential terms;
• short, trustworthy link;
• opt-out mechanism where required.

Example structure:

Brand: The product you asked about is back. View availability: [link]. Unsubscribe: [link]

This is a structure, not universal legal wording. Adapt the message purpose, identity, terms, and opt-out.

Avoid:

• all caps and excessive urgency;
• vague click here;
• hidden conditions;
• multiple offers and links;
• unsupported health, financial, or performance claims;
• personal or order data visible on the lock screen;
• accents or special characters added without checking segment cost and rendering.

SMS length and encoding affect the number of message segments billed and delivered. Klaviyo documents 160 characters for a single SMS, about 153 characters per segment once a message is split because an invisible ordering header is added, and 70 characters when an emoji or special character is present. One emoji can therefore multiply the segment count of a French message. Preview French characters, URLs, and unsubscribe text in the current Klaviyo composer.

Klaviyo no longer displays credits: message cost now appears in dollars, carrier fees included. There is no published per-country rate card, so read the rate that applies to your account and tier in Settings > Billing > Account Usage rather than quoting a figure from elsewhere.

Build a controlled campaign strategy

Create segments by both eligibility and relevance:

• current SMS promotional consent;
• France destination;
• recent engagement or purchase;
• specific product interest;
• requested restock;
• loyalty or VIP state;
• event or location relevance;
• recent message pressure;
• no unresolved support or order problem where promotion would be inappropriate.

Set exclusions:

• opted out or suppressed;
• already purchased;
• active in a higher-priority flow;
• messaged recently;
• outside market or sender support;
• product unavailable;
• offer ineligible.

Use SMS after a clear behavior, not as a substitute for broad email reach. A smaller relevant audience often produces better economics and fewer opt-outs.

Coordinate SMS with email and flows

Define channel priority:

• email for detail and durable reference;
• SMS for timely return or action;
• push for app context;
• transactional systems for necessary service;
• human support for exceptions.

Example campaign sequence:

1. email announces and explains;
2. SMS reaches consented high-intent people near a real deadline;
3. purchasers immediately exit;
4. post-purchase communication follows its own purpose.

Do not automatically add SMS to every Klaviyo flow. For welcome, checkout, post-purchase, replenishment, and winback, state the unique job of each text and the frequency impact.

The Klaviyo omnichannel marketing guide provides the wider framework for identity, consent, channel priority, pressure, and journey-level measurement.

Measure net and incremental value

Track:

• eligible profiles;
• messages attempted and delivered;
• segments consumed and cost;
• clicks and sessions;
• orders or target action;
• net revenue and contribution margin;
• opt-out and complaint;
• support contacts;
• overlap with email and flows;
• performance by use case and audience.

Calculate:

net contribution = net margin from incremental orders - SMS cost - offer cost - operating cost

Know the default attribution windows before quoting an SMS revenue figure. Klaviyo currently documents 5 days after an SMS click, 12 hours after an SMS delivery, 5 days after an email open or click, and 24 hours after a push open. These are editable in account settings.

Klaviyo attribution can help operate the program but does not prove incrementality. Use randomized holdouts or controlled rollout for material recurring campaigns and flows. Customers with high intent may have purchased without the text.

Monitor cost by destination and encoding. A campaign can look efficient on revenue while using more message segments than planned.

Run pre-send QA

• current France consent and source are present;
• sender type and market support are verified;
• brand identity is clear;
• unsubscribe works on a real device;
• quiet hours, Sunday, and public holiday controls are active;
• message segment count is understood;
• link and landing page are mobile-ready;
• offer, price, stock, and deadline agree;
• purchasers and conflicting journeys are excluded;
• sensitive data is absent;
• tracking and reporting are configured;
• incident owner can pause sending.

Test across representative French carriers and devices where possible. Carrier acceptance, display, link handling, and sender presentation can differ.

Not certain your French SMS consent and sender setup would pass scrutiny? Have it reviewed in a free 30-minute Klaviyo audit, no strings attached.

FAQ

Is Klaviyo SMS available in France?

Yes. Klaviyo's current availability table lists France, with a branded sender ID and SMS support. MMS is not currently available in Europe.

Can French recipients reply STOP?

No. The France sender type is a branded sender ID, which cannot receive inbound SMS, and France is not on Klaviyo's list of two-way keyword countries. A reply is never processed. Klaviyo adds a non-disableable unsubscribe link instead. Any objection reaching you by another route, support included, has to be applied in Klaviyo by your team.

What are Klaviyo's France quiet hours?

Its current guide lists no sends before 8 a.m., after 10 p.m., on Sundays, or on public holidays, and says carriers enforce these windows. Apply recipient local time and current requirements.

Does email consent include SMS?

No. Klaviyo requires SMS-specific agreement separate from email. Keep channel evidence and choices distinct.

How often should a brand send SMS?

There is no universal frequency. Use the minimum needed for timely, relevant customer jobs, respect the promised program, and monitor opt-out and incremental economics.

Operate SMS as a high-trust channel

Deliver helps international and French brands design consent, setup, campaigns, flows, QA, and measurement for Klaviyo SMS in France, and our Klaviyo flow specialists can build the program with your team. Request a France SMS program diagnostic.