diff --git a/app.js b/app.js
index 054263a..5437849 100644
--- a/app.js
+++ b/app.js
@@ -170,7 +170,7 @@ async function searchParcela(event) {
       typeNames: PARCEL_LAYER_NAME,
       outputFormat: "application/json",
       srsName: "EPSG:3857",
-      CQL_FILTER: `cod_parcela = '${escapeCqlLiteral(parcelNumber)}'`,
+      CQL_FILTER: buildParcelSearchFilter(parcelNumber),
     });
     const response = await fetch(`${API_WMS}?${params}`);
 
@@ -198,7 +198,7 @@ async function searchParcela(event) {
     updateParcelSearchStatus(
       features.length === 1
         ? `Found parcel ${parcelNumber}.`
-        : `Found ${features.length} parcels numbered ${parcelNumber}.`,
+        : `Found ${features.length} parcels matching ${parcelNumber}.`,
       "success",
     );
   } catch (error) {
@@ -207,6 +207,18 @@ async function searchParcela(event) {
   }
 }
 
+function buildParcelSearchFilter(parcelNumber) {
+  const escapedParcelNumber = escapeCqlLiteral(parcelNumber);
+
+  // Whole parcel numbers identify a group: 278 includes sub-parcels such as
+  // 278.1 and 278.2. A supplied sub-parcel number remains an exact lookup.
+  if (/^\d+$/.test(parcelNumber)) {
+    return `(cod_parcela = '${escapedParcelNumber}' OR cod_parcela LIKE '${escapedParcelNumber}.%')`;
+  }
+
+  return `cod_parcela = '${escapedParcelNumber}'`;
+}
+
 async function loadLayers() {
   updateStatus("Loading WMS layers...");