This article guides readers on how to send an SMS using Java and Spring Boot with the help of the Twilio SMS API. The tutorial requires Java Development Kit (JDK) version 8 or newer, Spring Tool Suite, a free or paid Twilio account, Apache Maven, and creates a new Spring Boot project. The project is set up by adding necessary dependencies in the pom.xml file, including spring-boot-starter, spring-boot-starter-web, spring-boot-starter-test, and twilio. A new package com.example.twilio.sms.controller is created to make a REST API that sends an SMS, using the @RestController annotation and handling HTTP requests with the @GetMapping annotation. The code initializes Twilio with environment variables for the account SID and auth token, creates a message sender, and returns a success message after sending the SMS. A new class SmsApplication.java is created to run the application, which starts on port 8080 and sends an SMS when hit with the URL http://localhost:8080/sendSMS.