diff --git a/tests/test-basic.sh b/tests/test-basic.sh
index f83143eb..bc085957 100755
--- a/tests/test-basic.sh
+++ b/tests/test-basic.sh
@@ -21,6 +21,9 @@ set -euo pipefail
 
 . $(dirname $0)/libtest.sh
 
+# This test looks for specific localized strings.
+export LC_ALL=C
+
 echo "1..3"
 
 ${FLATPAK} --version > version_out