Business Messaging Services for Korea and Global Markets

Send instant, dependable text messages to customers anywhere — order alerts, one-time passwords (OTP), two-factor authentication (2FA) codes, appointment reminders, shipping notifications, and promotional SMS campaigns.

With direct carrier connections in Korea and 200+ countries and a 97%+ delivery success rate, SureM makes sure your most important messages always arrive. Our SMS gateway supports high-volume bulk SMS sending, real-time delivery receipts (DLR), sender ID customization, and Unicode messaging for Korean and international character sets. Businesses in e-commerce, finance, healthcare, and logistics rely on SureM's SMS API for mission-critical notification delivery.

C-SMS (Concatenated SMS) automatically splits long text into multiple parts and reassembles them seamlessly on the recipient's phone — so you can send messages beyond the standard 160-character SMS limit without losing readability.

Standard SMS is capped at 160 characters (or 70 characters for Unicode/Korean text). C-SMS, also known as long SMS or multipart SMS, removes this constraint by chaining message segments transparently — the recipient sees one continuous message, regardless of length. This is especially valuable for sending detailed order summaries, compliance disclosures, multilingual notifications, and customer service responses.

With automatic overseas long-message processing and auto-routing across 200+ countries, SureM delivers your full message clearly, in any supported language. Our platform handles segment concatenation, international encoding, and carrier-level routing automatically — no additional configuration required on your end.

Connect through KakaoTalk, Korea's most-used messaging app with over 47 million monthly active users in South Korea — covering 93% of the Korean smartphone population, with business messages your customers actually open.

Send template-based Alimtalk notifications (orders, bookings, alerts) and Friendtalk (formerly Chingutalk) promotional messages — with automatic SMS fallback so no message is ever missed. Alimtalk is Korea's primary channel for transactional business notifications, while Friendtalk supports rich promotional content including images, buttons, and coupon links. Both channels require a verified KakaoTalk Business channel, which SureM helps you establish.

SureM guides you through channel setup, template approval, and delivery. With SureM's KakaoTalk Biz Message API, businesses can automate Alimtalk sends, track delivery and read status, and configure SMS fallback for recipients who disable KakaoTalk notifications — ensuring zero message loss across all customer segments.

RCS brings branded, interactive, app-like experiences right into your customer's default messaging inbox — with your logo, verified sender name, images, buttons, and carousels. Unlike SMS, RCS messages display your brand identity with a verified business profile, giving customers confidence that the message is authentic and reducing the risk of phishing and SMS fraud.

Richer than SMS and more trusted, RCS helps your business stand out while keeping the simple reach of a text message. RCS Business Messaging (RBM) supports suggested replies, quick-action buttons, product carousels, image galleries, and read receipts — transforming the native messaging inbox into a fully branded customer engagement channel. In South Korea, RCS is supported by all three major carriers (SKT, KT, LG U+) on both Android and iOS (since September 2024), with SureM providing direct carrier-grade RCS delivery.

For maximum reach, SureM automatically falls back to SMS when RCS is unavailable on a recipient's device or carrier — so you get rich messaging where it's supported and reliable SMS delivery everywhere else. No extra integration required.

SureM's voice service delivers your message as an automated phone call using text-to-speech, so time-critical information reaches the recipient even when a text message fails or goes unread. It's especially valuable for one-time passwords (OTP) and verification codes: if an SMS verification can't be delivered, SureM automatically places a voice call to read the code aloud.

This SMS-to-voice fallback removes the single biggest failure point in phone-number verification. Whether the recipient is on a landline, has SMS blocked, or is in an area with patchy text delivery, the verification still completes — improving sign-up conversion and protecting critical flows like login, payment confirmation, and account recovery.

Connect with customers on WhatsApp Business, used by 2.5 billion people across 180+ countries — the leading messaging channel in Latin America, Europe, the Middle East, India, and Southeast Asia. SureM provides WhatsApp Business API delivery as part of one unified messaging platform alongside SMS, RCS, and KakaoTalk.

Send pre-approved template messages for notifications, OTPs, and customer service conversations — with rich media (images, documents, video), interactive buttons, quick replies, and list selections. WhatsApp's verified Business Profile and end-to-end encryption give your brand the trust and authenticity needed for high-engagement customer communication globally.

SureM handles WhatsApp Business Account verification, template approval submissions, and ongoing campaign delivery. Combined with SureM's Korea-strong SMS, Kakao, and RCS coverage, you get a single integration that reaches customers wherever they are — in Korea or abroad — through their preferred messaging channel.