How long can an SMS be, and why use SMS?

SMS is an effective and direct form of communication, increasingly used by businesses for both order confirmations and marketing.

Although SMS may seem simple, there are technical details and financial considerations to be aware of – especially when it comes to the length of SMS messages.

Why use SMS for orders and marketing?

SMS messages offer a unique advantage compared to many other communication forms: they are almost always read – and often quickly. This makes them an ideal tool for sending:

• Order confirmations
• Information
• Automations – e.g. send SMS when a ticket or season pass is scanned
• Promotional offers and discount codes
• Status updates

With an average open rate above 90% and fast delivery time, SMS is a reliable and effective channel – especially for reaching customers on the go.

SMS in the Flex4B system

The SMS integration in the Flex4B system is designed with a focus on user-friendliness and flexibility. SMS messages can easily be sent automatically as part of the order flow.

SMS can also be sent through the automation module – for example, when tickets or cards are scanned.

The system handles all the technical aspects in the background, including SMS length management, recipient’s mobile operator, and sending through a professional gateway.

How long can an SMS be?

A standard SMS can contain up to 160 characters if it uses the classic GSM-7 character set. This includes letters, numbers, and the most common special characters.

Extended length for long messages

If your message exceeds 160 characters, it is split into several SMS messages – typically called a concatenated SMS. When this happens, the system uses a few characters to “glue” the messages together so the recipient sees it as one combined message. For instance, a 2-part SMS only has 153 characters per part:

• 1 SMS: up to 160 characters
• 2 SMS: up to 306 characters (2 x 153)
• 3 SMS: up to 459 characters (3 x 153)
• ... and so on

Use of Unicode (e.g. emojis and æøå)

If you use characters not included in the GSM-7 character set – such as emojis, Chinese characters, or certain special symbols – the message is automatically converted to Unicode (UCS-2). This has significant consequences:

• UCS-2 SMS can only contain 70 characters
• For concatenated UCS-2 SMS: 67 characters per part

Therefore, you should always pay attention to word choice and avoid unnecessary emojis and special characters if you want to keep the number of SMS messages low.

Why does it cost money to send an SMS from your website/webshop?

SMS messages sent via systems and webshops are delivered through professional SMS gateways. These gateways transmit the message to the mobile network on behalf of the sender – and this incurs costs. Here’s why:

1. Use of SMS gateway: The service ensures stable and fast delivery, including error monitoring and logs.
2. Carrier fees: Each SMS is billed by the mobile carrier, and the gateway passes on this cost.
3. Support and infrastructure: The gateway ensures message delivery – even under heavy load.

The price often depends on volume, destination, and the chosen gateway. Typically, prices range between DKK 0.25 and 0.90 per SMS depending on volume, but may be higher for foreign numbers.

Want to read more about the technology behind SMS and gateways? See more about SMS on Wikipedia

Do you want a webshop and ticketing system with SMS?

If you are looking for a webshop and a ticketing system with SMS that makes it easy to market to your customers, then the Flex4B system is a great choice.

Contact Flex4Business ApS for a free and non-binding meeting or quote.