diff --git a/afew/Database.py b/afew/Database.py
index 208ed2b..b3aa2c7 100644
--- a/afew/Database.py
+++ b/afew/Database.py
@@ -17,6 +17,7 @@ class Database:
 
     def __init__(self):
         self.db_path = self._calculate_db_path()
+        self.mail_root = self._calculate_mail_root()
         self.handle = None
 
     def _calculate_db_path(self):
@@ -34,6 +35,19 @@ def _calculate_db_path(self):
 
         return db_path
 
+    def _calculate_mail_root(self):
+        """
+        Calculates the mail root directory. This is the directory that contains
+        the maildir directories. It is used to determine the relative path of
+        messages for notmuch.
+        """
+        mail_root = notmuch_settings.get('database', 'mail_root', fallback=None)
+
+        if mail_root is None:
+            mail_root = self.db_path
+
+        return mail_root
+
     def __enter__(self):
         """
         Implements the context manager protocol.
diff --git a/afew/filters/FolderNameFilter.py b/afew/filters/FolderNameFilter.py
index 6b2a535..f10c4dd 100644
--- a/afew/filters/FolderNameFilter.py
+++ b/afew/filters/FolderNameFilter.py
@@ -14,7 +14,7 @@ def __init__(self, database, folder_blacklist='', folder_transforms='',
         super().__init__(database)
 
         self.__filename_pattern = '{mail_root}/(?P<maildirs>.*)/(cur|new)/[^/]+'.format(
-            mail_root=database.db_path.rstrip('/'))
+            mail_root=database.mail_root.rstrip('/'))
         self.__folder_explicit_list = set(shlex.split(folder_explicit_list))
         self.__folder_blacklist = set(shlex.split(folder_blacklist))
         self.__folder_transforms = self.__parse_transforms(folder_transforms)