What is a Sticky Sender?
Sticky Sender is a valuable feature for SMS or Voice marketing where all outbound customer contact comes from a single number. This 'sticky' or 'unchanging' number increases customer familiarity and trust. With a two-way Voice or SMS system, it also allows customers to contact businesses and organizations through the very same number.
Implementing Sticky Sender functionality in your SMS marketing application is one way to increase trust with your customers. While you may have many numbers in your phone number pool, keeping that common touchpoint for individual customer contact means you won't overwhelm anyone by changing outgoing numbers.
Furthermore, handling inbound messages from the same number means your customers can get back in touch with the number they trust instead of hunting down your company's primary support or sales number. A sticky sender also means customers can save your number into their phone book and not be surprised by an unknown texter when you do make outbound contact.
To use Sticky Sender with Twilio, configure a Messaging Service, which automatically assigns a consistent sender to each recipient you contact.
A Messaging Service, a part of Twilio Programmable Messaging, is the perfect partner for your SMS marketing or support operation. Using a set of rules, it will automatically use a sticky sender for numbers you have contacted before and assist you with the localization of new (uncontacted) numbers with Geo-Match functionality.

To turn on Sticky Sender, visit the Messaging Services section of the Twilio Console and enable it for your Messaging Service.
Additionally, you can build your own Sticky Sender functionality into an app with our Messaging API or our Voice API using Programmable Messaging and Programmable Voice, respectively.
To discuss how your business or organization can best use a Messaging Service, contact sales or get support for Twilio Messaging. Twilio does not recommend using a Sticky Sender for account security applications.