diff --git a/internal/adapters/arcgis/client.go b/internal/adapters/arcgis/client.go
index b4380f6..d4a2b9d 100644
--- a/internal/adapters/arcgis/client.go
+++ b/internal/adapters/arcgis/client.go
@@ -220,24 +220,29 @@ func actionFor(system string) string {
 	}
 }
 
-// likePattern builds the substring pattern the portal supports. Numeric tokens
-// are padded with spaces, matching the historical integration, so that "1" does
-// not incidentally match "10".
+// likePattern builds the substring pattern the portal supports. Only pure
+// numeric tokens (house numbers) are padded with spaces, so "1" does not
+// incidentally match "10". Ordinals ("3-я") and houses with a letter ("24а")
+// are left as-is: padding an ordinal breaks the match when it starts the
+// string, and precision is guaranteed by the local house filter anyway.
 func likePattern(canonical string) string {
 	parts := strings.Fields(canonical)
 	for i, part := range parts {
-		if containsDigit(part) {
+		if isPureDigits(part) {
 			parts[i] = " " + part + " "
 		}
 	}
 	return "%" + strings.Join(parts, "%") + "%"
 }
 
-func containsDigit(s string) bool {
+func isPureDigits(s string) bool {
+	if s == "" {
+		return false
+	}
 	for _, r := range s {
-		if r >= '0' && r <= '9' {
-			return true
+		if r < '0' || r > '9' {
+			return false
 		}
 	}
-	return false
+	return true
 }
diff --git a/internal/adapters/arcgis/client_test.go b/internal/adapters/arcgis/client_test.go
index b3b817a..f243db3 100644
--- a/internal/adapters/arcgis/client_test.go
+++ b/internal/adapters/arcgis/client_test.go
@@ -4,6 +4,7 @@ import (
 	"context"
 	"net/http"
 	"net/http/httptest"
+	"strings"
 	"testing"
 	"time"
 )
@@ -92,3 +93,18 @@ func TestQueryStripsDistrictSuffix(t *testing.T) {
 		t.Errorf("house not parsed at the boundary: %+v", rows[0].Unit)
 	}
 }
+
+// TestLikePattern guards the ordinal/house padding rule: padding an ordinal
+// that starts the string breaks the portal match.
+func TestLikePattern(t *testing.T) {
+	got := likePattern("3-я Механическая улица 24а")
+	if strings.Contains(got, " 3-я ") {
+		t.Errorf("ordinal must not be space-padded: %q", got)
+	}
+	if strings.Contains(got, " 24а ") {
+		t.Errorf("house with a letter must not be space-padded: %q", got)
+	}
+	if !strings.Contains(likePattern("Ленина улица 1"), "% 1 %") {
+		t.Errorf("pure numeric house must be space-padded: %q", likePattern("Ленина улица 1"))
+	}
+}