diff --git a/src/uu/numfmt/src/format.rs b/src/uu/numfmt/src/format.rs
index 77febdaaa41..e2cb093dea1 100644
--- a/src/uu/numfmt/src/format.rs
+++ b/src/uu/numfmt/src/format.rs
@@ -57,7 +57,7 @@ fn find_valid_number_with_suffix(s: &str, unit: Unit) -> Option<&str> {
     let accepts_suffix = unit != Unit::None;
     let accepts_i = [Unit::Auto, Unit::Iec(true)].contains(&unit);
 
-    let mut characters = s.chars().skip(numeric_part.len());
+    let mut characters = s[numeric_part.len()..].chars();
     let potential_suffix = characters.next();
     let potential_i = characters.next();
 
diff --git a/tests/by-util/test_numfmt.rs b/tests/by-util/test_numfmt.rs
index 33d810af269..ea731dde3e3 100644
--- a/tests/by-util/test_numfmt.rs
+++ b/tests/by-util/test_numfmt.rs
@@ -447,6 +447,21 @@ fn test_field_with_multibyte_whitespace_separator() {
         .stdout_only("1K 2000\n");
 }
 
+#[test]
+fn test_from_multibyte_decimal_separator_invalid_suffix() {
+    new_ucmd!()
+        .env("LC_ALL", "fr_FR. UTF-8")
+        .args(&["--from=si", "1٫€K"])
+        .fails_with_code(2)
+        .stderr_only("numfmt: invalid suffix in input '1٫€K': '€K'\n");
+
+    new_ucmd!()
+        .env("LC_ALL", "ar_SA.UTF-8")
+        .args(&["--from=auto", "1٫€Ki"])
+        .fails_with_code(2)
+        .stderr_only("numfmt: invalid suffix in input '1٫€Ki': '€Ki'\n");
+}
+
 #[test]
 fn test_format_selected_fields() {
     new_ucmd!()