diff --git a/gnu/packages/freedesktop.scm b/gnu/packages/freedesktop.scm
index 690621dee6..e23cc97683 100644
--- a/gnu/packages/freedesktop.scm
+++ b/gnu/packages/freedesktop.scm
@@ -500,7 +500,7 @@ (define-public modem-manager
     (source (origin
               (method url-fetch)
               (uri (string-append
-                    "http://www.freedesktop.org/software/ModemManager/"
+                    "https://www.freedesktop.org/software/ModemManager/"
                     "ModemManager-" version ".tar.xz"))
               (sha256
                (base32