diff --git a/backend/akr/src/main/java/fi/oph/akr/service/koodisto/PostalCodeService.java b/backend/akr/src/main/java/fi/oph/akr/service/koodisto/PostalCodeService.java
index cd7aa462f..879605139 100644
--- a/backend/akr/src/main/java/fi/oph/akr/service/koodisto/PostalCodeService.java
+++ b/backend/akr/src/main/java/fi/oph/akr/service/koodisto/PostalCodeService.java
@@ -44,11 +44,21 @@ public Pair<String, String> translateTown(final String t, final boolean retainCa
     if (t == null || t.isBlank()) {
       return Pair.of("", "");
     }
-    final String town = retainCase ? t : capitalize(t.toLowerCase());
-    if (fiToSv.containsKey(town)) {
-      return Pair.of(town, fiToSv.getOrDefault(town, town));
+    final String normalizedCase = capitalize(t.toLowerCase());
+    if (fiToSv.containsKey(normalizedCase)) {
+      return Pair.of(normalizedCase, fiToSv.getOrDefault(normalizedCase, normalizedCase));
+    } else if (svToFi.containsKey(normalizedCase)) {
+      return Pair.of(svToFi.getOrDefault(normalizedCase, normalizedCase), normalizedCase);
+    }
+
+    // If the normalized string wasn't found in translation maps,
+    // return the string itself, with either normalized or the original capitalization,
+    // depending on the source of the address.
+    if (retainCase) {
+      return Pair.of(t, t);
+    } else {
+      return Pair.of(normalizedCase, normalizedCase);
     }
-    return Pair.of(svToFi.getOrDefault(town, town), town);
   }
 
   public Pair<String, String> translateTown(final String t) {