SMS marketing in Turkey: IYS rules for ecommerce

What are the IYS rules for SMS marketing in Turkey?

Any SMS that contains a promotion, discount or even a holiday greeting is a commercial electronic message in Turkey and requires the recipient's prior consent. That consent must be registered in IYS (Ileti Yonetim Sistemi, the national message management system); consents you collect on your own store must be registered within three business days. Every message must include your MERSIS number and a free opt-out route.

SMS is one of the most direct channels in ecommerce: the message lands on the lock screen and is usually seen quickly. That power is also why the rules are strict. Below we cover the legal framework first, then the practical steps for turning SMS into a profitable channel. This article is for information only; get advice from legal counsel for your specific situation.

Which SMS messages need consent and which do not?

Commercial electronic messages are governed by Law No. 6563 on the Regulation of Electronic Commerce and the Regulation on Commercial Communication and Commercial Electronic Messages. Under the regulation, you need prior consent for messages sent to promote or market your goods and services, to promote your business, or to raise brand awareness with content such as celebrations and greetings. In other words, a "Happy holidays" SMS is covered too.

Message type	Prior consent needed?	Note
Campaigns, discounts, new product launches	Yes	Consent must be registered in IYS
Holiday and special day greetings	Yes	Counts as brand awareness messaging
Order confirmation, shipping and delivery updates	No	Must not promote any product
Payment, debt reminders, information updates	No	Must not contain promotion
Campaigns to merchants or tradespeople	No, but IYS registration and opt-out check required	Cannot send if they opted out

The key detail: if you add "Check out our new season" at the end of a shipping update, the message is no longer purely informational. Abandoned cart SMS reminders also encourage a purchase, so treat them as messages that require consent.

What is IYS and how does an ecommerce store comply?

IYS was added to the regulation in 2020 as the national system where commercial message consents and opt-outs are recorded. According to the amendment published in the Official Gazette:

• Individuals and companies that want to send commercial electronic messages must register with IYS.
• Commercial messages cannot be sent to recipients who do not have a consent on record in IYS.
• Consents collected outside IYS must be registered in IYS within three business days; unregistered consents are considered invalid.
• Opt-outs you receive must be reported to IYS within three business days. Recipients can also opt out directly through IYS.
• Your SMS provider must check IYS for consent before starting a send and must not start sending to recipients without consent.

In practice, this requires a working integration between your ecommerce platform, your SMS provider and IYS. Most SMS providers and Turkish ecommerce platforms offer one, but you remain responsible for registering consents on time.

How should you collect SMS consent?

The regulation sets clear rules for how consent is collected. According to the regulation text published by the Ministry of Trade:

1. Affirmative statement: consent must include the recipient's affirmative statement, name and contact address. For consents collected through IYS, the affirmative statement and contact address are enough.
2. No pre-ticked boxes: the affirmative statement cannot be pre-selected.
3. No precondition: marketing consent cannot be required in order to buy the product or service.
4. No consent requests by SMS: you cannot ask for consent by sending a commercial message to the recipient's number.
5. Confirmation: when consent is collected electronically, the recipient must be informed within 24 hours that consent was recorded, with an option to opt out (except for consents collected through IYS).
6. Burden of proof: for consents collected outside IYS, you must be able to prove consent was given.

On an ecommerce store, the cleanest approach is separate, unticked consent boxes for email and SMS on checkout and account forms. That way a customer can accept email but decline SMS. It also helps to plan your email list growth tactics together with this channel.

What must a promotional SMS include?

For messages sent through limited-space channels such as SMS, the regulation requires merchants to include their MERSIS number (Turkey's central trade registry number) in the message content, and tradespeople to include their name plus ID or tax number. You can add your brand name as well. Every commercial message must also include an opt-out option: an accessible route such as a customer service number, a short code or a URL dedicated to opt-outs, free and easy to use through the same channel the message was sent on.

Once an opt-out reaches you, you must stop sending commercial messages to that recipient within three business days. Consent records must be kept for three years from the date the consent expires. Complaints can be filed within three months of the message date through the Ministry's complaint portal or provincial trade directorates.

How do you make SMS a profitable channel?

Compliance is the baseline; the real question is whether SMS makes you money. SMS costs more per message than email and customers have less patience for it. Build it in this order:

1. Perfect transactional messages first. Order, shipping and delivery updates need no consent and directly improve the customer experience.
2. Send to segments. Instead of blasting the whole list, pick consented customers who visited in the last 90 days, bought from a specific category or left items in their cart.
3. Lead with the value. Put the offer and deadline in the first sentence, and use a short link on your own brand domain.
4. Cap frequency. Several promotional texts a week push opt-outs up quickly. Check the opt-out rate after every send.
5. Measure with UTMs. Tag every SMS link so you can see SMS revenue separately in GA4.

Example: assume a campaign sent to 20,000 consented subscribers brings 200 orders. Subtract the sending cost and the margin impact of the discount from the contribution of those 200 orders. If the result is not positive, narrow the send to a smaller, higher-intent segment. If you are weighing SMS against WhatsApp, our WhatsApp marketing guide helps with channel choice.

What are common SMS mistakes?

• Sending campaigns to an old customer list without registering it in IYS.
• Adding promotional lines to shipping updates.
• Dropping the MERSIS number or opt-out route to save characters.
• Processing opt-outs in the SMS tool without syncing them to your store platform and IYS.
• Sending late at night; even where it is not prohibited, it increases negative reactions.

If you want to bring SMS, email and paid channels together in one growth plan, you can request a free growth analysis through our contact page.

Key takeaways

• Promotional and greeting SMS messages require prior consent, registered in IYS.
• Consents collected outside IYS must be registered within three business days or they become invalid.
• Every SMS needs a MERSIS number and a free opt-out route; opt-outs must be honored within three business days.
• Order and shipping updates need no consent but must not contain promotion.
• Use SMS for segmented, capped-frequency sends and measure every link with UTMs.