Send-time optimization

Send-Time Optimization

Use Send-Time Optimization (STO) to pick the best time to send out a communication to customers and increase the click and open rates.

This feature works based on the history of a person`s interactions with messages: whether they opened the message or clicked a URL inside it. Infobip automatically tracks the history of opens and clicks for the sent messages and optimizes the sending time based on these metrics. But keep in mind that every channel has its own specifics. You can track the history in the Contact Information section of a person profile in People.

These are different options per Channel that can be used with STO:

SMSClick Rate

Open Rate
Click Rate

VoicePhone Pickup Rate
PushOpen Rate

Open Rate
Click Rate

ViberOpen Rate
TelegramOpen Rate

Remember to select Track Clicks when creating the messages so that this data can be used in optimization.

STO in Flow

When adding a send element (SMS, Email, Voice, Push, or WhatsApp) in Flow, you can activate Send-Time Optimization to allow the tool to choose the best sending time within the next 24h.

Add the channel you want to use, click on it, and then click Show Advanced Options in the side panel. Then toggle Send-Time Optimization.

Enable STO in Flow

If you want to use the Delivery Time Window as well, go for it, and the maximum amount of time before sending a message will also be taken into account.

STO in Broadcast

Send-Time Optimization is available in Broadcast. Select Send-Time Optimization under Message scheduling when you create a broadcast using the SMS channel.

As STO relies on data collected from a person's activity to optimize the send time, STO will not work with files in Broadcast. This is because files do not contain a history of activity that is needed for STO to work.

Enable STO in Broadcast

Campaign Analytics with STO

After you launch your Flow or Broadcast, the metrics will appear as soon as we start receiving the data related to the sent messages.

STO Analytics

Analytics for any communication with STO consist of three groups of data:

  • Optimized Messages - sent using STO. Both Broadcast and Flow will automatically include the customers for whom there is enough information to use STO, and the communication will be split into 2 groups: optimized messages (90%) and control messages (10%).
  • Control Messages - sent without STO at the scheduled time. The control group is automatically included at the campaign launch or within the scheduled delivery time window. The control group helps identify whether STO worked better than regular scheduling.
  • Non-Optimized Messages - regular scheduling. The rest of the recipients, for whom there is not enough data to use STO, are marked as “Non-Optimized Messages.” They are sent based on regular scheduling.
STO Analytics Dashboard

The image above does not contain any actual data; it is only meant to give you an idea of what the results page in Broadcast looks like.

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