diff --git a/src/email_address/mod.rs b/src/email_address/mod.rs
new file mode 100644
index 0000000..db1f77d
--- /dev/null
+++ b/src/email_address/mod.rs
@@ -0,0 +1,35 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, you can obtain one at https://mozilla.org/MPL/2.0/.
+
+//! Email address type.
+
+use serde::de::{Deserialize, Deserializer, Error, Unexpected};
+
+use validate;
+
+#[cfg(test)]
+mod test;
+
+#[derive(Clone, Debug, Default, Serialize, PartialEq)]
+pub struct EmailAddress(pub String);
+
+/// Email address type.
+///
+/// Validates and then lowercases the address during deserialization.
+impl<'d> Deserialize<'d> for EmailAddress {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'d>,
+    {
+        let value: String = Deserialize::deserialize(deserializer)?;
+        if validate::email_address(&value) {
+            Ok(EmailAddress(value.to_lowercase()))
+        } else {
+            Err(D::Error::invalid_value(
+                Unexpected::Str(&value),
+                &"email address",
+            ))
+        }
+    }
+}
diff --git a/src/email_address/test.rs b/src/email_address/test.rs
new file mode 100644
index 0000000..de5f832
--- /dev/null
+++ b/src/email_address/test.rs
@@ -0,0 +1,43 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// // file, you can obtain one at https://mozilla.org/MPL/2.0/.
+
+use serde_test::{assert_de_tokens, Token};
+
+use super::*;
+
+#[derive(Serialize, Deserialize, PartialEq, Debug)]
+struct TestEmailStruct {
+    email: EmailAddress,
+}
+
+#[test]
+fn always_lowercase_email() {
+    let expected = TestEmailStruct {
+        email: EmailAddress(String::from("foo@example.com")),
+    };
+    assert_de_tokens(
+        &expected,
+        &[
+            Token::Struct {
+                name: "TestEmailStruct",
+                len: 1,
+            },
+            Token::Str("email"),
+            Token::Str("foo@example.com"),
+            Token::StructEnd,
+        ],
+    );
+    assert_de_tokens(
+        &expected,
+        &[
+            Token::Struct {
+                name: "TestEmailStruct",
+                len: 1,
+            },
+            Token::Str("email"),
+            Token::Str("FOO@EXAMPLE.COM"),
+            Token::StructEnd,
+        ],
+    );
+}
diff --git a/src/lib.rs b/src/lib.rs
index 7c244f7..f735ee7 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -73,6 +73,7 @@ pub mod app_errors;
 pub mod auth_db;
 pub mod bounces;
 pub mod duration;
+pub mod email_address;
 pub mod logging;
 pub mod message_data;
 pub mod providers;
diff --git a/src/send/mod.rs b/src/send/mod.rs
index deda680..2d94ebe 100644
--- a/src/send/mod.rs
+++ b/src/send/mod.rs
@@ -11,11 +11,11 @@ use rocket::{
     Data, Outcome, Request, State,
 };
 use rocket_contrib::{Json, Value};
-use serde::de::{Deserialize, Deserializer, Error, Unexpected};
 
 use app_errors::{AppError, AppErrorKind, AppResult};
 use auth_db::DbClient;
 use bounces::Bounces;
+use email_address::EmailAddress;
 use message_data::MessageData;
 use providers::{Headers, Providers};
 use validate;
@@ -29,26 +29,6 @@ struct Body {
     html: Option<String>,
 }
 
-#[derive(Clone, Debug, Default, Serialize, PartialEq)]
-pub struct EmailAddress(pub String);
-
-impl<'d> Deserialize<'d> for EmailAddress {
-    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
-    where
-        D: Deserializer<'d>,
-    {
-        let value: String = Deserialize::deserialize(deserializer)?;
-        if validate::email_address(&value) {
-            Ok(EmailAddress(value.to_lowercase()))
-        } else {
-            Err(D::Error::invalid_value(
-                Unexpected::Str(&value),
-                &"email address",
-            ))
-        }
-    }
-}
-
 #[derive(Debug, Deserialize)]
 struct Email {
     to: EmailAddress,
diff --git a/src/send/test.rs b/src/send/test.rs
index 0a9a60c..6bed125 100644
--- a/src/send/test.rs
+++ b/src/send/test.rs
@@ -7,9 +7,7 @@ use rocket::{
     http::{ContentType, Status},
     local::Client,
 };
-use serde_test::{assert_de_tokens, Token};
 
-use super::EmailAddress;
 use app_errors::{self, AppError, AppErrorKind};
 use auth_db::DbClient;
 use bounces::Bounces;
@@ -43,46 +41,6 @@ fn setup() -> Client {
     Client::new(server).unwrap()
 }
 
-#[derive(Serialize, Deserialize, PartialEq, Debug)]
-struct TestEmailStruct {
-    email: EmailAddress,
-}
-
-#[test]
-fn always_lowercase_email() {
-    let lowercase = TestEmailStruct {
-        email: EmailAddress(String::from("foo@example.com")),
-    };
-    assert_de_tokens(
-        &lowercase,
-        &[
-            Token::Struct {
-                name: "TestEmailStruct",
-                len: 1,
-            },
-            Token::Str("email"),
-            Token::Str("foo@example.com"),
-            Token::StructEnd,
-        ],
-    );
-
-    let uppercase = TestEmailStruct {
-        email: EmailAddress(String::from("foo@example.com")),
-    };
-    assert_de_tokens(
-        &uppercase,
-        &[
-            Token::Struct {
-                name: "TestEmailStruct",
-                len: 1,
-            },
-            Token::Str("email"),
-            Token::Str("FOO@EXAMPLE.COM"),
-            Token::StructEnd,
-        ],
-    );
-}
-
 #[test]
 fn single_recipient() {
     let client = setup();
diff --git a/src/settings/mod.rs b/src/settings/mod.rs
index c13e8f8..f064173 100644
--- a/src/settings/mod.rs
+++ b/src/settings/mod.rs
@@ -13,8 +13,8 @@ use config::{Config, ConfigError, Environment, File};
 use serde::de::{Deserialize, Deserializer, Error, Unexpected};
 
 use duration::Duration;
+use email_address::EmailAddress;
 use logging::MozlogLogger;
-use send::EmailAddress;
 use serialize;
 use validate;