diff --git a/org.gnome.Geary.json b/org.gnome.Geary.json
index 5c983803..b65c3d49 100644
--- a/org.gnome.Geary.json
+++ b/org.gnome.Geary.json
@@ -224,7 +224,7 @@
                 {
                     "type": "git",
                     "url": "https://github.com/jstedfast/gmime.git",
-                    "branch": "master"
+                    "branch": "3.2.7"
                 }
             ]
         },
diff --git a/org.gnome.Geary.yaml b/org.gnome.Geary.yaml
index 908ed45d..f47a86d9 100644
--- a/org.gnome.Geary.yaml
+++ b/org.gnome.Geary.yaml
@@ -223,7 +223,9 @@ modules:
     sources:
       - type: git
         url: https://github.com/jstedfast/gmime.git
-        branch: master
+        # Pin to 3.2.7 until 3.2.8 is released, or the mainline branch
+        # is pre-bumped to same.
+        branch: 3.2.7
 
   # Geary dependency
   - name: libpeas