Deliverability

When building your SMS campaigns, you must stay aligned with best practices and compliance to avoid poor performance.

Many factors influence the optimal delivery of your messages, and you should be fully aware of their impact when using SMS as your communication channel.

Poor practices may lead to overcharging and potentially give customers the impression that you are delivering spam, especially if you are sending long messages that are spliced and delivered over several separate messages.

You are advised to follow the guidelines in this section. In addition, make sure that you check out International SMS coverage and Connectivity for full information about local regulations and terms of use.

Invalid Numbers and Format Errors

If you add an invalid or incorrectly formatted mobile number in the web interface, the system will detect it and will stop messages from being sent to them. This stops you from being charged for a message which will never be received.

This is an additional service offered by Infobip which enables you to clear and tidy up your number database. It is recommended to use it periodically to boost deliverability and improve campaign results through higher delivery rates.

Duplicate Messages and Numbers

In your campaigns, you should not send a message multiple times to a single number.

If you set up your campaign to send the same message to the same number twice, when the campaign is launched, the Infobip web interface will detect the duplicate message and won't send it again.

Number Formatting

It is strongly recommended to use the E.164 number format. E.164 numbers are internationally standardized to a 15-digit max. length.

Phone numbers must start with a country code, followed by a network code, then the subscriber number. Plus prefixes + are not required.

Phone numbers that are not E.164 formatted may work, depending on the handset or network.

Example: a Croatian number is formatted as 385981234567, while a UK number is formatted as 447712345678.

Roaming Numbers

When launching a campaign, there is a possibility that the recipient will be in roaming. All efforts will be made and the platform will forward these messages further to reach the recipient, however, the delivery in such situations can't be guaranteed.

Scheduling Messages

Advance message scheduling can be set up using the Infobip API or directly in the web interface.

Use the scheduling options in the web interface when creating campaigns to specify start and end times according to time zones.

Scheduling through HTTP API requires Client to set sentAt to the desired value (2015-07-07T17:00:00.000+01:00)

Scheduling over the SMPP API requires setting schedule_delivery_time to the desired value by entering it in the relative time format (“070605040302100R”). This means that the message will be delivered in 7 years, 6 months, 5 days, 4 hours, 3 minutes, 2 seconds and 1 tenth of second from now.

Country-Specific Requirements

See the section on International SMS coverage and Connectivity to find out more about country-specific regulations for sender names, and more.

Long Messages

All SMS messages are charged per message. When you send long SMS messages, they end up being broken up into several messages because of message length restrictions.

This means all of these individual messages which are part of one campaign are being charged individually.

Message length allowances vary between mobile networks. It is suggested to constrain sending to no more than 5-7 long SMS parts. Contact your dedicated Infobip point of contact for more information around specific network limitations.

Verified SMS

Enable VSMS to raise brand awareness by exposing brand information presented to customers at the top of message windows.

With SMS message verification preventing phishing types of attacks, it is ensured that each message is sent by you and that the message hasn’t been altered during the message delivery process. Each verified message will be labeled as ‘Verified’.

Verified SMS enhances the user experience for all types of SMS communication. However, we especially recommend using VSMS for the following use cases:

• Messages of high confidentiality and importance (PINs, fraud alerts, warnings, account balances)
• Order confirmations and reminders
• Transactional and promotional messages containing links