What is an alphanumeric sender ID?
An alphanumeric sender ID enables organizations to send one-way text messages to recipients using a custom, recognizable string made up of any combination of letters and numbers.
This makes the alphanumeric sender ID much more recognizable so that users can quickly identify the sender if they are not saved in their phone’s contacts. Sender IDs can be used to present anything from a company name or department to the name of a government organization.
The drawback is that recipients of messages sent using a Sender ID can’t reply to the message, which restricts the use cases to one-way SMS alerts and informational messages.
What characters are allowed in an alphanumeric sender ID?
Sender IDs can contain both numeric and alpha characters (0-9, a-z, A-Z) and the space character, i.e., ASCII code = 32. The maximum length is 11 characters. In some countries, certain carriers may also impose a minimum length.
Examples of alphanumeric sender IDs:
- LoginCode (9 characters)
- FlashSale (9 characters)
- 123GO (5 characters)
- Sale20 (6 characters)
- CityAlerts (10 characters)
How to get an alphanumeric Sender ID?
An alphanumeric sender ID can be obtained from most enterprise SMS providers.
This option is not available in all countries, and in some cases, organizations have to pre-register their sender IDs to prevent duplication and fraudulent use. These include major markets like Brazil, Indonesia, Mexico, and the Philippines. These countries may charge a one-time or monthly setup fee for this service.
What are the benefits?
There are several benefits to using an alphanumeric sender ID for SMS messaging:
- Increased brand recognition: Your business or brand name becomes instantly recognizable in the recipient’s inbox, reinforcing your branding efforts.
- Improved trust and open rates: Customers are much more likely to trust and open messages from a recognizable name than from a random phone number. This can significantly boost your SMS open rates.
- Enhanced professionalism: An alphanumeric sender ID presents a more professional image than a generic phone number, suggesting that your business is legitimate and established.
- Better deliverability: Messages from recognizable sender IDs are less likely to be mistaken for spam and blocked by carriers. This improves your message deliverability rates.
- Increased customer engagement: Higher open rates and a sense of trust can lead to greater customer engagement with your messages.
Use cases: Where alphanumeric sender IDs excel
Alphanumeric sender IDs aren’t a one-size-fits-all solution, but they are incredibly powerful in certain scenarios:
- Appointment reminders: “DrSmith” lets patients know their appointment is coming up without needing to open the message.
- Order updates: “MyShop” sending order confirmations and shipping notifications builds anticipation.
- Promotions and sales: “FlashSale” creates a sense of urgency and exclusivity.
- Urgent alerts: “CityAlert” or “Security” command immediate attention.
- Verification codes (2FA): “YourBank” providing login codes increases security and legitimacy.
What are the potential limitations of alphanumeric sender IDs?
Potential limitations of alphanumeric sender IDs are:
- Not for replies: Recipients generally can’t reply directly to messages sent with an alphanumeric sender ID.
- Country-specific: Not all countries support them, and registration rules vary.
- Potential costs: Some providers might charge fees for using alphanumeric sender IDs.
Alphanumeric vs. fixed vs. numeric sender ID
Here’s a breakdown of the distinctions between alphanumeric, fixed sender ID, and numeric sender ID:
| Alphanumeric sender ID | Fixed sender ID | Numeric sender ID | |
|---|---|---|---|
| Type | Letters and numbers | Brand/company name | Phone number |
| Example | MyStore | Infobip | +1 (555) 123-4567 |
| Character limit | Up to 11 characters | Variable | Typically 10–15 digits (up to 20 characters, depending on country and operator specifications) |
| Two-way messaging | Not supported | Not supported | Supported |
| Country support | Limited, some require registration | Limited, some require registration | Widely supported |
| Costs | Can be more expensive | Can be more expensive | Usually cheapest |
FAQs
Unfortunately, traditional alphanumeric sender IDs cannot contain spaces. While you can’t use a traditional space, you can use capitalization, hyphens, or underscores to make your sender ID more readable.
Unfortunately, you generally cannot directly reply to an SMS sent from an alphanumeric sender ID. Alphanumeric sender IDs are designed primarily for one-way communication, focused on broadcasting messages like notifications, alerts, and promotions.
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