diff --git a/backend/src/main/java/com/morris/quizly/configurations/SecurityConfiguration.java b/backend/src/main/java/com/morris/quizly/configurations/SecurityConfiguration.java
index e5446f1..eafaacc 100644
--- a/backend/src/main/java/com/morris/quizly/configurations/SecurityConfiguration.java
+++ b/backend/src/main/java/com/morris/quizly/configurations/SecurityConfiguration.java
@@ -37,6 +37,7 @@ public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Excepti
                 .authorizeHttpRequests(authorize -> authorize
                         .requestMatchers(
                                 "/api/auth/**",
+                                "/api/subscriptions/**",
                                 "/api/quiz-generation/**",
                                 "/api/quiz-retrieval/**",
                                 "/login",
diff --git a/backend/src/main/java/com/morris/quizly/controllers/AuthController.java b/backend/src/main/java/com/morris/quizly/controllers/AuthController.java
index cda3dac..06f3f8e 100644
--- a/backend/src/main/java/com/morris/quizly/controllers/AuthController.java
+++ b/backend/src/main/java/com/morris/quizly/controllers/AuthController.java
@@ -1,9 +1,7 @@
 package com.morris.quizly.controllers;
 
-import com.morris.quizly.models.security.AuthRequest;
-import com.morris.quizly.models.security.JwtTokenProvider;
-import com.morris.quizly.models.security.Roles;
-import com.morris.quizly.models.security.SignupRequest;
+import com.morris.quizly.models.security.*;
+import com.morris.quizly.services.NotificationService;
 import com.morris.quizly.services.QuizlyUserDetailsService;
 import com.morris.quizly.utils.FileUtil;
 import org.slf4j.Logger;
@@ -17,7 +15,6 @@
 import org.springframework.security.core.Authentication;
 import org.springframework.security.core.AuthenticationException;
 import org.springframework.security.core.context.SecurityContextHolder;
-import org.springframework.security.core.userdetails.UserDetails;
 import org.springframework.security.core.userdetails.UsernameNotFoundException;
 import org.springframework.security.crypto.password.PasswordEncoder;
 import org.springframework.web.bind.annotation.*;
@@ -25,6 +22,7 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.UUID;
 
 @RestController
 @RequestMapping("/api/auth")
@@ -35,6 +33,7 @@ public class AuthController {
     private final PasswordEncoder passwordEncoder;
     private final JwtTokenProvider jwtTokenProvider;
     private final QuizlyUserDetailsService quizlyUserDetailsService;
+    private final NotificationService notificationService;
 
     private static final String USER_DETAILS = "userDetails";
     private static final String ACCESS_TOKEN = "accessToken";
@@ -53,11 +52,13 @@ public class AuthController {
 
     @Autowired
     public AuthController(AuthenticationManager authenticationManager, PasswordEncoder passwordEncoder,
-                          JwtTokenProvider jwtTokenProvider, QuizlyUserDetailsService quizlyDetailsService) {
+                          JwtTokenProvider jwtTokenProvider, QuizlyUserDetailsService quizlyDetailsService,
+                          NotificationService notificationService) {
         this.authenticationManager = authenticationManager;
         this.passwordEncoder = passwordEncoder;
         this.jwtTokenProvider = jwtTokenProvider;
         this.quizlyUserDetailsService = quizlyDetailsService;
+        this.notificationService = notificationService;
     }
 
     @PostMapping("/login")
@@ -168,6 +169,7 @@ public ResponseEntity<?> signup(@ModelAttribute SignupRequest signupRequest) {
             LOGGER.error("Image is null: {}", e.getMessage());
         }
         LOGGER.info(imageBase64EncodedStr);
+        String signupToken = UUID.randomUUID().toString(); // make this secure
         com.morris.quizly.models.security.UserDetails userDetails = com.morris.quizly.models.security.UserDetails.builder()
                 .firstName(signupRequest.getFirstName())
                 .lastName(signupRequest.getLastName())
@@ -179,12 +181,14 @@ public ResponseEntity<?> signup(@ModelAttribute SignupRequest signupRequest) {
                 .accountNonLocked(true)
                 .accountNonExpired(true)
                 .credentialsNonExpired(true)
-                .enabled(true)
+                .enabled(false)
+                .signupToken(signupToken)
                 .build();
 
         try {
             UserDetails userDetailsResult = quizlyUserDetailsService.save(userDetails);
-            if (userDetailsResult.isEnabled()) {
+            if (userDetailsResult.isAccountNonLocked()) {
+                notificationService.sendSignupConfirmationEmailAndLink(userDetailsResult, signupToken);
                 return ResponseEntity.ok()
                         .body(SIGNUP_SUCCESS);
             }
diff --git a/backend/src/main/java/com/morris/quizly/controllers/SubscriptionController.java b/backend/src/main/java/com/morris/quizly/controllers/SubscriptionController.java
new file mode 100644
index 0000000..42715d7
--- /dev/null
+++ b/backend/src/main/java/com/morris/quizly/controllers/SubscriptionController.java
@@ -0,0 +1,68 @@
+package com.morris.quizly.controllers;
+
+import com.morris.quizly.models.security.UserDetails;
+import com.morris.quizly.services.QuizlyUserDetailsService;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+@RequestMapping("/api/subscriptions")
+public class SubscriptionController {
+
+    private final QuizlyUserDetailsService userService;
+
+    @Autowired
+    public SubscriptionController(QuizlyUserDetailsService userService) {
+        this.userService = userService;
+    }
+
+    @GetMapping("/confirm-signup")
+    public ResponseEntity<String> confirmSignup(@RequestParam("token") String token) {
+        UserDetails user = userService.findBySignupToken(token);
+        if (null == user) {
+            return ResponseEntity.status(HttpStatus.BAD_REQUEST).body("Invalid token");
+        }
+        userService.updateEnabledStatus(user, true);
+
+        String htmlResponse = "<html>" +
+                "<head>" +
+                "<style>" +
+                "body { font-family: Arial, sans-serif; text-align: center; padding: 20px; }" +
+                "h2 { color: #333; }" +
+                ".logo { margin: 20px auto; }" +
+                ".container { max-width: 600px; margin: 0 auto; text-align: center; }" +
+                ".button { background-color: #000; color: #fff; padding: 10px 20px; text-decoration: none; display: inline-block; margin-top: 20px; }" +
+                "</style>" +
+                "</head>" +
+                "<body>" +
+                "<div class='container'>" +
+                "<img class='logo' src='/images/quizly-logo.png' alt='Quizly Logo'>" +
+                "<h2>Thanks for confirming signup with Quizly, " + user.getFirstName() + "!</h2>" +
+                "</div>" +
+                "<script>" +
+                "window.onload = function() {" +
+                "   var newTab = window.open('', '_blank');" +
+                "   newTab.document.write(\"<html><head><style>" +
+                "body { font-family: Arial, sans-serif; text-align: center; padding: 20px; }" +
+                "h1 { color: #333; }" +
+                ".logo { margin: 20px auto; }" +
+                ".container { max-width: 600px; margin: 0 auto; text-align: center; }" +
+                "</style></head><body><div class='container'>" +
+                "<h1>Subscription confirmed successfully!</h1>" +
+                "</div></body></html>\");" +
+                "};" +
+                "</script>" +
+                "</body>" +
+                "</html>";
+        HttpHeaders headers = new HttpHeaders();
+        headers.setContentType(MediaType.TEXT_HTML);
+        return ResponseEntity.ok().headers(headers).body(htmlResponse);
+    }
+}
diff --git a/backend/src/main/java/com/morris/quizly/models/security/UserDetails.java b/backend/src/main/java/com/morris/quizly/models/security/UserDetails.java
index 166bd6e..ae666a6 100644
--- a/backend/src/main/java/com/morris/quizly/models/security/UserDetails.java
+++ b/backend/src/main/java/com/morris/quizly/models/security/UserDetails.java
@@ -43,6 +43,7 @@ public class UserDetails implements org.springframework.security.core.userdetail
     private boolean credentialsNonExpired;
     private boolean enabled;
     private String lockedReason;
+    private String signupToken;
 
     private int flagCount;
     List<SystemFlag> flags;
diff --git a/backend/src/main/java/com/morris/quizly/repositories/UserRepository.java b/backend/src/main/java/com/morris/quizly/repositories/UserRepository.java
index e432cc3..da4ec64 100644
--- a/backend/src/main/java/com/morris/quizly/repositories/UserRepository.java
+++ b/backend/src/main/java/com/morris/quizly/repositories/UserRepository.java
@@ -20,6 +20,15 @@ public interface UserRepository extends MongoRepository<UserDetails, String> {
      */
     Optional<UserDetails> findByUsername(String username);
 
+    /**
+     * Find user by signup token. Signup tokens are used to confirm application subscriptions.
+     *
+     * @param token {@link String} signup token
+     *
+     * @return {@link UserDetails}
+     */
+    Optional<UserDetails> findBySignupToken(String token);
+
     /**
      * Determines if an account is non-locked.
      *
diff --git a/backend/src/main/java/com/morris/quizly/services/EmailService.java b/backend/src/main/java/com/morris/quizly/services/EmailService.java
index 052dc50..08f8ecb 100644
--- a/backend/src/main/java/com/morris/quizly/services/EmailService.java
+++ b/backend/src/main/java/com/morris/quizly/services/EmailService.java
@@ -1,5 +1,13 @@
 package com.morris.quizly.services;
 
 public interface EmailService {
+
+    /**
+     * Sends email.
+     *
+     * @param to      {@link String} email recipient
+     * @param subject {@link String} Subject
+     * @param body    {@link String} email content
+     */
     void sendEmail(String to, String subject, String body);
 }
diff --git a/backend/src/main/java/com/morris/quizly/services/NotificationService.java b/backend/src/main/java/com/morris/quizly/services/NotificationService.java
index 52bb07c..d5e37aa 100644
--- a/backend/src/main/java/com/morris/quizly/services/NotificationService.java
+++ b/backend/src/main/java/com/morris/quizly/services/NotificationService.java
@@ -1,5 +1,7 @@
 package com.morris.quizly.services;
 
+import com.morris.quizly.models.security.UserDetails;
+
 public interface NotificationService {
 
     /**
@@ -11,5 +13,11 @@ public interface NotificationService {
      */
     boolean notifyAdmin(String message);
 
-    boolean subscribeUserToAppUserTopic(String userEmailAddress);
+    /**
+     * Sends signup confirmation email to user.
+     *
+     * @param user  {@link UserDetails}
+     * @param token {@link String} confirmation token
+     */
+    void sendSignupConfirmationEmailAndLink(UserDetails user, String token);
 }
diff --git a/backend/src/main/java/com/morris/quizly/services/QuizlyUserDetailsService.java b/backend/src/main/java/com/morris/quizly/services/QuizlyUserDetailsService.java
index 552b35b..2aad1be 100644
--- a/backend/src/main/java/com/morris/quizly/services/QuizlyUserDetailsService.java
+++ b/backend/src/main/java/com/morris/quizly/services/QuizlyUserDetailsService.java
@@ -33,4 +33,20 @@ public interface QuizlyUserDetailsService extends UserDetailsService {
      * @return boolean
      */
     boolean isUserNameInUse(String username);
+
+    /**
+     * Find user by signup token.
+     *
+     * @param token {@link String} signup token
+     * @return {@link UserDetails}
+     */
+    UserDetails findBySignupToken(String token);
+
+    /**
+     * Modifies user enabled status.
+     *
+     * @param user {@link UserDetails} user
+     * @param enabled boolean
+     */
+    void updateEnabledStatus(UserDetails user, boolean enabled);
 }
diff --git a/backend/src/main/java/com/morris/quizly/services/impl/EmailServiceImpl.java b/backend/src/main/java/com/morris/quizly/services/impl/EmailServiceImpl.java
index 2902cd9..8d7c730 100644
--- a/backend/src/main/java/com/morris/quizly/services/impl/EmailServiceImpl.java
+++ b/backend/src/main/java/com/morris/quizly/services/impl/EmailServiceImpl.java
@@ -1,50 +1,63 @@
 package com.morris.quizly.services.impl;
 
 import com.morris.quizly.services.EmailService;
+import com.sendgrid.Method;
+import com.sendgrid.Request;
+import com.sendgrid.Response;
+import com.sendgrid.SendGrid;
+import com.sendgrid.helpers.mail.Mail;
+import com.sendgrid.helpers.mail.objects.ClickTrackingSetting;
+import com.sendgrid.helpers.mail.objects.Content;
+import com.sendgrid.helpers.mail.objects.Email;
+import com.sendgrid.helpers.mail.objects.TrackingSettings;
+import org.jetbrains.annotations.NotNull;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.stereotype.Service;
 
-import javax.mail.*;
-import javax.mail.internet.InternetAddress;
-import javax.mail.internet.MimeMessage;
-import java.util.Properties;
+import java.io.IOException;
 
 @Service
 public class EmailServiceImpl implements EmailService {
+    private static final Logger LOGGER = LoggerFactory.getLogger(EmailServiceImpl.class);
 
-    @Value("$gmail.username")
-    private String admin;
-
-    @Value("${gmail.password}")
-    private String password;
+    @Value("${sendgrid.signup.confirmation.api}")
+    private String key;
 
     @Override
     public void sendEmail(String to, String subject, String body) {
-        Properties props = new Properties();
-        props.put("mail.smtp.auth", "true");
-        props.put("mail.smtp.starttls.enable", "true");
-        props.put("mail.smtp.host", "smtp.gmail.com");
-        props.put("mail.smtp.port", "587");
-
-        Session session = Session.getInstance(props,
-                new javax.mail.Authenticator() {
-                    protected PasswordAuthentication getPasswordAuthentication() {
-                        return new PasswordAuthentication(admin, password);
-                    }
-                });
+        Mail mail = getMail(to, subject, body);
 
+        SendGrid sg = new SendGrid(key);
+        Request request = new Request();
         try {
-            Message message = new MimeMessage(session);
-            message.setFrom(new InternetAddress(admin));
-            message.setRecipients(Message.RecipientType.TO, InternetAddress.parse(to));
-            message.setSubject(subject);
-            message.setText(body);
-
-            Transport.send(message);
-
-            System.out.println("Email sent successfully");
-        } catch (MessagingException e) {
-            throw new RuntimeException(e);
+            request.setMethod(Method.POST);
+            request.setEndpoint("mail/send");
+            request.setBody(mail.build());
+            Response response = sg.api(request);
+            System.out.println(response.getStatusCode());
+            System.out.println(response.getBody());
+            System.out.println(response.getHeaders());
+        } catch (IOException e) {
+            LOGGER.error("Error sending email: {}", e.getMessage());
         }
     }
+
+    @NotNull
+    private Mail getMail(String to, String subject, String body) {
+        Email from = new Email("ai.quizly@gmail.com");
+        Email toEmail = new Email(to);
+        Content content = new Content("text/plain", body);
+        Mail mail = new Mail(from, subject, toEmail, content);
+
+        // Disable click tracking
+        TrackingSettings trackingSettings = new TrackingSettings();
+        ClickTrackingSetting clickTrackingSetting = new ClickTrackingSetting();
+        clickTrackingSetting.setEnable(false);
+        clickTrackingSetting.setEnableText(false);
+        trackingSettings.setClickTrackingSetting(clickTrackingSetting);
+        mail.setTrackingSettings(trackingSettings);
+        return mail;
+    }
 }
diff --git a/backend/src/main/java/com/morris/quizly/services/impl/NotificationServiceImpl.java b/backend/src/main/java/com/morris/quizly/services/impl/NotificationServiceImpl.java
index da90b87..febdb22 100644
--- a/backend/src/main/java/com/morris/quizly/services/impl/NotificationServiceImpl.java
+++ b/backend/src/main/java/com/morris/quizly/services/impl/NotificationServiceImpl.java
@@ -4,8 +4,7 @@
 import com.amazonaws.services.sns.AmazonSNSClientBuilder;
 import com.amazonaws.services.sns.model.PublishRequest;
 import com.amazonaws.services.sns.model.PublishResult;
-import com.amazonaws.services.sns.model.SubscribeRequest;
-import com.amazonaws.services.sns.model.SubscribeResult;
+import com.morris.quizly.models.security.UserDetails;
 import com.morris.quizly.services.EmailService;
 import com.morris.quizly.services.NotificationService;
 import org.slf4j.Logger;
@@ -20,12 +19,11 @@ public class NotificationServiceImpl implements NotificationService {
     @Value("${sns.systemsFlaggingTopicArn}")
     private String snsSystemsFlaggingTopicArn;
 
-    @Value("${sns.applicationUserTopicArn}")
-    private String snsApplicationUserTopicArn;
-
     private final AmazonSNS amazonSNSClient;
     private final EmailService emailService;
 
+    private static final String DEV_CONFIRMATION_LINK = "http://localhost:8081/api/subscriptions/confirm-signup?token=";
+
     public NotificationServiceImpl(EmailService emailService) {
         this.amazonSNSClient = AmazonSNSClientBuilder.defaultClient();
         this.emailService = emailService;
@@ -39,20 +37,20 @@ public boolean notifyAdmin(String message) {
     }
 
     @Override
-    public boolean subscribeUserToAppUserTopic(String userEmailAddress) {
+    public void sendSignupConfirmationEmailAndLink(UserDetails user, String token) {
         try {
-            SubscribeRequest subscribeRequest = new SubscribeRequest()
-                    .withTopicArn(snsApplicationUserTopicArn)
-                    .withProtocol("email")
-                    .withEndpoint(userEmailAddress);
-            SubscribeResult subscribeResult = amazonSNSClient.subscribe(subscribeRequest);
-            sendCustomConfirmationEmail(userEmailAddress, subscribeResult.getSubscriptionArn());
-            return true;
+            sendCustomConfirmationEmail(user, token);
         } catch (Exception e) {
-            LOGGER.error("Error subscribing user to Application User SNS Topic: {}", e.getMessage());
-            return false;
+            LOGGER.error("Error sending signup confirmation email: {}", e.getMessage());
         }
     }
 
-    private void sendCustomConfirmationEmail(String userEmail, String subscriptionArn) {}
+    private void sendCustomConfirmationEmail(UserDetails user, String token) {
+        String confirmationLink = DEV_CONFIRMATION_LINK + token;
+        String emailBody = String.format(
+                "Welcome to Quizly, %s! We're excited you've decided to join this educational journey with us.\n" +
+                        "Please confirm your subscription by clicking the link below:\n\n" + confirmationLink, user.getFirstName()
+        );
+        emailService.sendEmail(user.getEmailAddress(), "Quizly Signup Confirmation", emailBody);
+    }
 }
diff --git a/backend/src/main/java/com/morris/quizly/services/impl/QuizlyUserDetailsServiceImpl.java b/backend/src/main/java/com/morris/quizly/services/impl/QuizlyUserDetailsServiceImpl.java
index 34158c6..d9f6dce 100644
--- a/backend/src/main/java/com/morris/quizly/services/impl/QuizlyUserDetailsServiceImpl.java
+++ b/backend/src/main/java/com/morris/quizly/services/impl/QuizlyUserDetailsServiceImpl.java
@@ -6,6 +6,10 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.data.mongodb.core.MongoTemplate;
+import org.springframework.data.mongodb.core.query.Criteria;
+import org.springframework.data.mongodb.core.query.Query;
+import org.springframework.data.mongodb.core.query.Update;
 import org.springframework.security.core.userdetails.UsernameNotFoundException;
 import org.springframework.stereotype.Service;
 
@@ -14,10 +18,12 @@ public class QuizlyUserDetailsServiceImpl implements QuizlyUserDetailsService {
     private static final Logger LOGGER = LoggerFactory.getLogger(QuizlyUserDetailsServiceImpl.class);
 
     private final UserRepository userRepository;
+    private final MongoTemplate mongoTemplate;
 
     @Autowired
-    public QuizlyUserDetailsServiceImpl(UserRepository userRepository) {
+    public QuizlyUserDetailsServiceImpl(UserRepository userRepository, MongoTemplate mongoTemplate) {
         this.userRepository = userRepository;
+        this.mongoTemplate = mongoTemplate;
     }
 
     @Override
@@ -26,6 +32,12 @@ public UserDetails loadUserByUsername(String username) throws UsernameNotFoundEx
                 .orElseThrow(() -> new UsernameNotFoundException("User not found: " + username));
     }
 
+    @Override
+    public UserDetails findBySignupToken(String token) {
+        return userRepository.findBySignupToken(token)
+                .orElseThrow(() -> new UsernameNotFoundException("token not found: " + token));
+    }
+
     @Override
     public UserDetails save(UserDetails userDetails) {
         return userRepository.save(userDetails);
@@ -35,4 +47,11 @@ public UserDetails save(UserDetails userDetails) {
     public boolean isUserNameInUse(String userName) {
         return userRepository.findByUsername(userName).isPresent();
     }
+
+    @Override
+    public void updateEnabledStatus(UserDetails user, boolean enabled) {
+        Query query = new Query(Criteria.where("_id").is(user.getId()));
+        Update update = new Update().set("enabled", enabled);
+        mongoTemplate.updateFirst(query, update, UserDetails.class);
+    }
 }
diff --git a/pom.xml b/pom.xml
index cbc116b..df9d314 100644
--- a/pom.xml
+++ b/pom.xml
@@ -176,9 +176,9 @@
 		</dependency>
 
 		<dependency>
-			<groupId>com.sun.mail</groupId>
-			<artifactId>javax.mail</artifactId>
-			<version>1.6.2</version>
+			<groupId>com.sendgrid</groupId>
+			<artifactId>sendgrid-java</artifactId>
+			<version>4.10.1</version>
 		</dependency>
 
 		<!-- JSON Dependencies -->