What Are the Masked Sender ID Countries?

A Masked Sender ID is a pre-assigned or route-provided Sender ID used in destinations where custom Sender IDs may not be fully supported, may be restricted, or may be changed by the local mobile operator.

In some countries, mobile networks do not always allow the sender name entered by the user to appear exactly as submitted. Instead, the SMS may be delivered using a masked, shared, numeric, or predefined Sender ID depending on the destination network, route type, telecom regulation, and operator filtering rules.

This guide lists the countries and network operators where a masked Sender ID may be required or applied when sending SMS messages through BulkSMSOnline.

If you are new to Sender IDs, you can also review the Sender ID Knowledge Base or learn more about route behavior from the BulkSMSOnline SMS Routing page.

What Does Masked Sender ID Mean?

A masked Sender ID means the recipient may see a different Sender ID from the one submitted in your SMS request. This can happen when the destination country or mobile operator does not allow open custom Sender IDs, requires special routing, or applies sender replacement for compliance and filtering purposes.

For example, you may submit your company name as the Sender ID, but the message may be delivered using a predefined Sender ID or a network-approved sender format. This behavior is controlled by the destination route, operator rules, and local telecom requirements.

Why Do Some Countries Require Masked Sender ID?

Some countries and mobile operators apply Sender ID controls to reduce spam, protect users from impersonation, prevent unauthorized brand usage, and comply with local telecommunications regulations.

Masked Sender ID may be applied for several reasons:

• The destination country does not support open custom Sender IDs.
• The operator requires messages to pass through approved sender formats.
• The route uses a predefined Sender ID for better compatibility.
• The sender name is restricted, blocked, or not registered in that destination.
• The mobile network rewrites or replaces the Sender ID before delivery.
• The message content or sender format triggers operator filtering rules.

Because Sender ID behavior can vary by operator and route, we recommend testing before sending important or high-volume SMS traffic.

Masked Sender ID Country List

The following table shows the country list that requires or may apply a masked Sender ID.

Important Notes About Masked Sender ID

• Sender ID display may vary: The Sender ID shown to the recipient may be different from the Sender ID submitted in your request.
• Operator rules can change: Mobile networks may update Sender ID requirements, filtering policies, or routing rules without prior notice.
• Testing is recommended: Always send a test SMS before sending high-volume or important traffic.
• Custom Sender ID is not guaranteed: In masked Sender ID destinations, the final sender name may be replaced by the route or operator.
• Content still matters: Spam, phishing links, misleading offers, unauthorized brand names, or restricted content may be filtered or blocked.
• Delivery reports should be checked: After sending, monitor delivery reports where available to understand the final message status.

When Should You Contact Support?

You should contact BulkSMSOnline support if you are unsure whether your destination country requires a masked Sender ID, if your Sender ID is not appearing as expected, or if you need guidance before sending large SMS traffic.

For faster assistance, please provide the following details:

• Your BulkSMSOnline username or registered email address.
• The destination country you are sending to.
• The Sender ID you want to use.
• A sample of your SMS message content.
• The recipient network or operator, if known.
• The route or sending method used, such as web panel, HTTP API, REST API, or SMPP.
• The message ID or API response, if available.

Related Sender ID and Country Restriction Guides

Sender ID requirements can be different from one country to another. If your destination is not listed here, or if you want to compare other Sender ID categories, you may find these guides helpful:

• Are There Country Restrictions for SMS Messages?
• Alphanumeric Only Sender ID Country List
• No Restriction Sender ID Country List
• Registered Sender ID Country List
• Sender ID Knowledge Base

Need Help Checking a Masked Sender ID Destination?

If you are planning to send SMS to a country listed above, it is best to test the route first and confirm how the Sender ID appears on the recipient’s phone. This is especially important for OTP messages, account alerts, marketing campaigns, payment notifications, booking reminders, and other customer-facing messages.

You can review country coverage from the Bulk SMS Countries page, learn more about route behavior from the SMS Routing page, or contact our team through the Contact Us page.

For destination rates and route pricing, please visit the BulkSMSOnline Pricing page.