diff --git a/geneit_backend/src/controllers/auth_controller.rs b/geneit_backend/src/controllers/auth_controller.rs
index be86373..47aa8fc 100644
--- a/geneit_backend/src/controllers/auth_controller.rs
+++ b/geneit_backend/src/controllers/auth_controller.rs
@@ -29,9 +29,20 @@ pub async fn create_account(
         return Ok(HttpResponse::BadRequest().json("Size constraints were not respected!"));
     }
 
-    // TODO : check the mail address
+    // Check if email is already attached to an account
+    match users_service::exists_email(&req.email).await {
+        Ok(false) => {}
+        Ok(true) => {
+            return Ok(HttpResponse::Conflict()
+                .json("An account with the same email address already exists!"));
+        }
+        Err(e) => {
+            log::error!("Failed to check email existence! {}", e);
+            return Err(ErrorInternalServerError(e));
+        }
+    }
 
-    // Create  the account
+    // Create the account
     let user_id = users_service::create_account(&req.name, &req.email)
         .await
         .map_err(|e| {
diff --git a/geneit_backend/src/services/users_service.rs b/geneit_backend/src/services/users_service.rs
index 0e337c7..caed4d0 100644
--- a/geneit_backend/src/services/users_service.rs
+++ b/geneit_backend/src/services/users_service.rs
@@ -20,3 +20,15 @@ pub async fn create_account(name: &str, email: &str) -> anyhow::Result<User> {
         Ok(res)
     })
 }
+
+/// Check if an email address is already associated with an account
+pub async fn exists_email(email: &str) -> anyhow::Result<bool> {
+    db_connection::execute(|conn| {
+        let count: i64 = users::table
+            .filter(users::email.eq(email))
+            .count()
+            .get_result(conn)?;
+
+        Ok(count != 0)
+    })
+}