diff --git a/api/app/services/geocoding.py b/api/app/services/geocoding.py
index 53b212f..ff6679d 100644
--- a/api/app/services/geocoding.py
+++ b/api/app/services/geocoding.py
@@ -1,17 +1,78 @@
 from __future__ import annotations
 
 import hashlib
+import re
 from typing import Any
 
 from app.config import CACHE_TTL_GEOCODE, NOMINATIM_BASE_URL, NOMINATIM_USER_AGENT
 from app.http_client import get_client
 from app.database import get_cached_json, set_cached_json
 
+_POSTAL_ONLY = re.compile(r"^\d{4,5}$")
+_POSTAL_CITY = re.compile(r"^(\d{4,5})\s+(.+)$")
+
 
 def _query_hash(query: str) -> str:
     return hashlib.sha256(query.strip().lower().encode("utf-8")).hexdigest()
 
 
+def _parse_nominatim_item(item: dict[str, Any]) -> dict[str, Any]:
+    address = item.get("address") or {}
+    label = item.get("display_name", "")
+    place = (
+        address.get("city")
+        or address.get("town")
+        or address.get("village")
+        or address.get("municipality")
+        or address.get("county")
+        or label.split(",")[0]
+    )
+    return {
+        "label": label,
+        "place": place,
+        "lat": float(item["lat"]),
+        "lon": float(item["lon"]),
+        "type": item.get("type"),
+        "postcode": address.get("postcode"),
+        "county": address.get("county"),
+        "state": address.get("state"),
+    }
+
+
+def _country_codes_for_postal(postal: str) -> str:
+    if len(postal) == 5:
+        return "de"
+    return "at,ch"
+
+
+def _build_search_params(query: str, limit: int) -> dict[str, Any]:
+    base = {
+        "format": "jsonv2",
+        "addressdetails": 1,
+        "limit": limit,
+    }
+    city_match = _POSTAL_CITY.match(query)
+    if city_match:
+        postal, city = city_match.groups()
+        return {
+            **base,
+            "postalcode": postal,
+            "city": city.strip(),
+            "countrycodes": _country_codes_for_postal(postal),
+        }
+    if _POSTAL_ONLY.match(query):
+        return {
+            **base,
+            "postalcode": query,
+            "countrycodes": _country_codes_for_postal(query),
+        }
+    return {
+        **base,
+        "q": query,
+        "countrycodes": "de,at,ch",
+    }
+
+
 async def _nominatim_get(path: str, params: dict[str, Any]) -> Any:
     headers = {"User-Agent": NOMINATIM_USER_AGENT, "Accept-Language": "de"}
     client = get_client()
@@ -21,7 +82,10 @@ async def _nominatim_get(path: str, params: dict[str, Any]) -> Any:
 
 
 async def search_places(query: str, limit: int = 8) -> list[dict[str, Any]]:
-    if len(query.strip()) < 2:
+    query = query.strip()
+    if len(query) < 2:
+        return []
+    if query.isdigit() and len(query) < 4:
         return []
 
     qhash = _query_hash(f"search:{query}:{limit}")
@@ -29,40 +93,8 @@ async def search_places(query: str, limit: int = 8) -> list[dict[str, Any]]:
     if cached is not None:
         return cached
 
-    raw = await _nominatim_get(
-        "/search",
-        {
-            "q": query,
-            "format": "jsonv2",
-            "addressdetails": 1,
-            "limit": limit,
-            "countrycodes": "de,at,ch",
-        },
-    )
-    results = []
-    for item in raw:
-        address = item.get("address") or {}
-        label = item.get("display_name", "")
-        place = (
-            address.get("city")
-            or address.get("town")
-            or address.get("village")
-            or address.get("municipality")
-            or address.get("county")
-            or label.split(",")[0]
-        )
-        results.append(
-            {
-                "label": label,
-                "place": place,
-                "lat": float(item["lat"]),
-                "lon": float(item["lon"]),
-                "type": item.get("type"),
-                "postcode": address.get("postcode"),
-                "county": address.get("county"),
-                "state": address.get("state"),
-            }
-        )
+    raw = await _nominatim_get("/search", _build_search_params(query, limit))
+    results = [_parse_nominatim_item(item) for item in raw]
 
     await set_cached_json(
         "geocode_cache",
diff --git a/frontend/app.js b/frontend/app.js
index dc2fd8e..ac0ca8b 100644
--- a/frontend/app.js
+++ b/frontend/app.js
@@ -758,7 +758,7 @@ function toggleWarningsOnMap() {
 }
 
 async function searchPlaces(query) {
-  if (query.length < 2) {
+  if (query.length < 2 || (/^\d+$/.test(query) && query.length < 4)) {
     el("searchResults").classList.add("hidden");
     return;
   }
@@ -767,7 +767,7 @@ async function searchPlaces(query) {
     const results = data.results || [];
     el("searchResults").innerHTML = results.length ? results.map((r, i) => `
       <li role="option" data-index="${i}">
-        <strong>${r.place}</strong>
+        <strong>${r.place}${r.postcode ? ` (${r.postcode})` : ""}</strong>
         <span>${r.label}</span>
       </li>
     `).join("") : `<li class="muted">Keine Treffer</li>`;
@@ -776,6 +776,7 @@ async function searchPlaces(query) {
       item.addEventListener("click", () => {
         const r = results[Number(item.dataset.index)];
         setLocation({ place: r.place, lat: r.lat, lon: r.lon });
+        el("placeSearch").value = r.postcode || r.place;
         el("searchResults").classList.add("hidden");
         loadAll();
       });
diff --git a/frontend/style.css b/frontend/style.css
index a5d47f0..875e91f 100644
--- a/frontend/style.css
+++ b/frontend/style.css
@@ -249,11 +249,13 @@ html[data-theme="light"] textarea { background: rgba(255,255,255,0.92); }
   grid-template-columns: 2fr 1.2fr 1fr 1fr auto;
   gap: 12px;
   align-items: end;
+  position: relative;
+  z-index: 30;
 }
-.search-wrap { position: relative; }
+.search-wrap { position: relative; z-index: 2; }
 .search-results {
   position: absolute;
-  z-index: 50;
+  z-index: 100;
   left: 0; right: 0;
   top: calc(100% + 6px);
   list-style: none;