ZNS (Zalo Notification Service)

ZNS (Zalo Notification Service) is a service for sending Zalo-approved template messages from a business’s Zalo Official Account to a customer’s phone number, used for order confirmations, OTP codes, appointment reminders and after-sales care. Zalo’s current documentation calls the service ZBS Template Message.

What is Zalo ZNS?

A ZNS message appears under the OA’s name, with a logo, an information table, parameters such as the customer’s name or order code, and buttons to call, open a website, leave a rating or pay. A business needs three accounts: the OA, a ZBS account (where templates are created, credit is topped up and reports live) and an app (AppID) that the OA authorizes to send through the API. Teams without developers can send by campaign, uploading an Excel file. Templates are reviewed in about 2 to 3 business days (Zalo Business Solutions, Introduction to ZBS Template Message, accessed October 2026).

The three ZNS message purposes

Every template must carry one purpose, which Zalo calls a Tag (Zalo Business Solutions, General template review rules, October 2026 version). Sending hours apply from October 15, 2026 (Zalo Business Solutions, notice, October 2026).

Content and promotion rules

• Messages may only go to people who have already transacted with the business. The single exception is a verification code when a customer creates a new account.
• Promotional content belongs in Tag 3 only. Button links in Tag 1 and Tag 2 templates may not invite people to buy or download an app.
• Links and phone numbers go on buttons, never in the message body. No abbreviations, no icons, no shortened links.
• Each customer receives at most 1 Promotion message per day (30 per month) from a given OA. Customers who do not follow the OA receive these messages in the Business Box folder.

Zalo rates each OA’s sending quality by the share of recipients who report its messages. The recommended safe level is under 0.1% per day. Poor quality cuts the OA’s sending quota and disables the affected templates (Zalo Business Solutions, Sending quality mechanism, accessed October 2026).

ZNS pricing

Prices exclude VAT and apply only to successfully processed messages (Zalo Business Solutions, ZBS Template Message pricing, accessed October 2026): OTP, transfer request and voucher templates cost VND 300 per message; all other types cost VND 200. The first button in each category is free, and each additional button in the same category costs VND 100. Sending by UID (the user’s ID with the OA) is cheaper than sending by phone number.

Example (hypothetical): a fashion shop has 10,000 orders a month, and each order gets 1 confirmation message with 1 button: 10,000 x 200 = VND 2,000,000. Adding vouchers for 3,000 past customers costs 3,000 x 300 = VND 900,000. The total is VND 2,900,000, before VAT.

Personal data rules

A ZNS phone list is personal data. Since January 1, 2026, Vietnam’s Personal Data Protection Law No. 91/2025/QH15 requires consent for each purpose: a customer who left a phone number to get a quote has not agreed to receive promotional ZNS. The vendor whose tool sends your ZNS is a data processor and needs a signed agreement under Decree 356/2025/ND-CP. Details are in our guide to the Vietnam personal data protection law for marketers.

Frequently asked questions

How is ZNS different from regular OA messages?

OA consultation messages and broadcasts only reach people who have interacted with or follow the OA. ZNS reaches the phone numbers of customers who have transacted with you, even if they do not follow the OA, but it requires an approved template and is paid per message.

Do I need a paid OA plan to send ZNS?

Sending through the API from a ZBS account requires a verified business OA on the Growth or Comprehensive plan (Zalo Business Solutions, OA pricing, accessed October 2026).

ZNS is usually triggered from a CRM or a marketing automation tool. If you want to connect them so order confirmations and reminders go out automatically to the right people, contact Adtek.