diff --git a/grep.c b/grep.c
index 5bc0f4f32a..c7c06ae08d 100644
--- a/grep.c
+++ b/grep.c
@@ -472,7 +472,8 @@ static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt
 		}
 		options |= PCRE2_CASELESS;
 	}
-	if (!opt->ignore_locale && is_utf8_locale() && has_non_ascii(p->pattern))
+	if (!opt->ignore_locale && is_utf8_locale() && has_non_ascii(p->pattern) &&
+	    !(!opt->ignore_case && (p->fixed || p->is_fixed)))
 		options |= PCRE2_UTF;
 
 	p->pcre2_pattern = pcre2_compile((PCRE2_SPTR)p->pattern,
diff --git a/t/t7812-grep-icase-non-ascii.sh b/t/t7812-grep-icase-non-ascii.sh
index 96c3572056..531eb59d57 100755
--- a/t/t7812-grep-icase-non-ascii.sh
+++ b/t/t7812-grep-icase-non-ascii.sh
@@ -68,9 +68,9 @@ test_expect_success GETTEXT_LOCALE,LIBPCRE2 'PCRE v2: grep ASCII from invalid UT
 '
 
 test_expect_success GETTEXT_LOCALE,LIBPCRE2 'PCRE v2: grep non-ASCII from invalid UTF-8 data' '
-	test_might_fail git grep -h "æ" invalid-0x80 >actual &&
+	git grep -h "æ" invalid-0x80 >actual &&
 	test_cmp expected actual &&
-	test_must_fail git grep -h "(*NO_JIT)æ" invalid-0x80 &&
+	git grep -h "(*NO_JIT)æ" invalid-0x80 &&
 	test_cmp expected actual
 '