diff --git a/changelog.md b/changelog.md
--- a/changelog.md
+++ b/changelog.md
@@ -1,2 +1,5 @@
+## 0.1.0.6
+* Add compatibility with base64-1.0.
+
 ## 0.1.0.5
 * Metadata update.
diff --git a/gmail-simple.cabal b/gmail-simple.cabal
--- a/gmail-simple.cabal
+++ b/gmail-simple.cabal
@@ -1,5 +1,5 @@
 name: gmail-simple
-version: 0.1.0.5
+version: 0.1.0.6
 synopsis: Simple library for Google Mail (GMail).
 description:
   Easy-to-use library to interact with the Google Mail API.
diff --git a/src/Network/GMail/Simple.hs b/src/Network/GMail/Simple.hs
--- a/src/Network/GMail/Simple.hs
+++ b/src/Network/GMail/Simple.hs
@@ -79,6 +79,9 @@
 #endif
 import qualified Network.HTTP.Simple as HTTP
 import Data.ByteString.Base64 (encodeBase64)
+#if MIN_VERSION_base64(1,0,0)
+import Data.Base64.Types (extractBase64)
+#endif
 import Network.HTTP.Media (MediaType)
 import qualified Network.HTTP.Media as Media
 import Data.Time.Clock (NominalDiffTime)
@@ -259,6 +262,9 @@
 #endif
     $ Text.replace "+" "-"
     $ Text.replace "/" "_"
+#if MIN_VERSION_base64(1,0,0)
+    $ extractBase64
+#endif
     $ encodeBase64
     $ encodeUtf8 $ Text.concat
         [ "From: " <> mail_sender mail <> " <" <> mailAddressText sender <> ">\r\n"