diff --git a/builtin/tag.c b/builtin/tag.c
index f8266888cca97f..af3af3f64935c3 100644
--- a/builtin/tag.c
+++ b/builtin/tag.c
@@ -582,7 +582,7 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 		die(_("%s: cannot lock the ref"), ref.buf);
 	if (write_ref_sha1(lock, object, NULL) < 0)
 		die(_("%s: cannot update the ref"), ref.buf);
-	if (force && hashcmp(prev, object))
+	if (force && !is_null_sha1(prev) && hashcmp(prev, object))
 		printf(_("Updated tag '%s' (was %s)\n"), tag, find_unique_abbrev(prev, DEFAULT_ABBREV));
 
 	strbuf_release(&buf);
diff --git a/t/t7004-tag.sh b/t/t7004-tag.sh
index f5a79b13aecf40..c8d6e9f88cc36f 100755
--- a/t/t7004-tag.sh
+++ b/t/t7004-tag.sh
@@ -104,6 +104,18 @@ test_expect_success 'creating a tag using HEAD directly should succeed' '
 	tag_exists myhead
 '
 
+test_expect_success '--force can create a tag with the name of one existing' '
+	tag_exists mytag &&
+	git tag --force mytag &&
+	tag_exists mytag'
+
+test_expect_success '--force is moot with a non-existing tag name' '
+	git tag newtag >expect &&
+	git tag --force forcetag >actual &&
+	test_cmp expect actual
+'
+git tag -d newtag forcetag
+
 # deleting tags:
 
 test_expect_success 'trying to delete an unknown tag should fail' '