diff --git a/CHANGES b/CHANGES
index c230e593d0..f2f5d91a1c 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,6 @@
+5187.	[test]		Set time zone before running any tests in dnstap_test.
+			[GL #940]
+
 5186.	[cleanup]	More dnssec-keygen manual tidying. [GL !1678]
 
 5184.	[bug]		Missing unlocks in sdlz.c. [GL #936]
diff --git a/lib/dns/tests/dnstap_test.c b/lib/dns/tests/dnstap_test.c
index 4fb42be0e7..916bd72856 100644
--- a/lib/dns/tests/dnstap_test.c
+++ b/lib/dns/tests/dnstap_test.c
@@ -312,9 +312,6 @@ totext_test(void **state) {
 
 	UNUSED(state);
 
-	/* make sure text conversion gets the right local time */
-	setenv("TZ", "PST8", 1);
-
 	result = dns_dt_open(TAPSAVED, dns_dtmode_file, mctx, &handle);
 	assert_int_equal(result, ISC_R_SUCCESS);
 
@@ -381,6 +378,9 @@ main(void) {
 		cmocka_unit_test_setup_teardown(totext_test, _setup, _teardown),
 	};
 
+	/* make sure text conversion gets the right local time */
+	setenv("TZ", "PST8", 1);
+
 	return (cmocka_run_group_tests(tests, NULL, NULL));
 #else
 	print_message("1..0 # Skip dnstap not enabled\n");