diff --git a/src/components/admin/billing/new-invoice-form.tsx b/src/components/admin/billing/new-invoice-form.tsx
index 296a1b1..f4c8809 100644
--- a/src/components/admin/billing/new-invoice-form.tsx
+++ b/src/components/admin/billing/new-invoice-form.tsx
@@ -1,6 +1,6 @@
 "use client";
 
-import { useState } from "react";
+import { useEffect, useRef, useState } from "react";
 import { useRouter } from "next/navigation";
 import { useTranslations } from "next-intl";
 import { Card } from "@/components/ui/card";
@@ -104,25 +104,14 @@ export function NewInvoiceForm({ orgs }: Props) {
           <label className="text-xs uppercase tracking-wider text-text-muted">
             {t("newInvoiceOrgLabel")}
           </label>
-          <select
+          <OrgCombobox
+            orgs={orgs}
             value={orgId}
-            onChange={(e) => onOrgChange(e.target.value)}
-            className="px-3 py-2 rounded-md border border-border bg-surface-2 text-sm"
-          >
-            <option value="">{t("newInvoiceOrgPlaceholder")}</option>
-            {orgs.map((o) => (
-              <option
-                key={o.zitadelOrgId}
-                value={o.zitadelOrgId}
-                disabled={!o.hasBillingAddress}
-              >
-                {o.companyName ?? o.zitadelOrgId}
-                {!o.hasBillingAddress
-                  ? ` (${t("newInvoiceOrgNoBilling")})`
-                  : ""}
-              </option>
-            ))}
-          </select>
+            onChange={onOrgChange}
+            placeholder={t("newInvoiceOrgPlaceholder")}
+            noBillingLabel={t("newInvoiceOrgNoBilling")}
+            noMatchesLabel={t("newInvoiceOrgNoMatches")}
+          />
           {selected && !selected.hasBillingAddress && (
             <p className="text-xs text-error mt-1">
               {t("newInvoiceOrgBillingMissing")}
@@ -164,3 +153,138 @@ export function NewInvoiceForm({ orgs }: Props) {
     </Card>
   );
 }
+
+/**
+ * Searchable single-select for the billing org. Replaces a plain
+ * <select> that would become unusable once the customer list grows:
+ * type to filter by company name or org id, arrow keys to move, Enter
+ * to pick. Orgs without a billing snapshot stay selectable but are
+ * flagged — selecting one surfaces the existing "billing missing"
+ * warning and keeps the submit button disabled.
+ */
+function OrgCombobox({
+  orgs,
+  value,
+  onChange,
+  placeholder,
+  noBillingLabel,
+  noMatchesLabel,
+}: {
+  orgs: OrgEntry[];
+  value: string;
+  onChange: (orgId: string) => void;
+  placeholder: string;
+  noBillingLabel: string;
+  noMatchesLabel: string;
+}) {
+  const [open, setOpen] = useState(false);
+  const [query, setQuery] = useState("");
+  const [hi, setHi] = useState(0);
+  const ref = useRef<HTMLDivElement>(null);
+
+  const selected = orgs.find((o) => o.zitadelOrgId === value) || null;
+  const display = selected ? selected.companyName ?? selected.zitadelOrgId : "";
+
+  // Close on outside click so the dropdown doesn't linger.
+  useEffect(() => {
+    const onDoc = (e: MouseEvent) => {
+      if (ref.current && !ref.current.contains(e.target as Node)) {
+        setOpen(false);
+      }
+    };
+    document.addEventListener("mousedown", onDoc);
+    return () => document.removeEventListener("mousedown", onDoc);
+  }, []);
+
+  const q = query.trim().toLowerCase();
+  const filtered = q
+    ? orgs.filter(
+        (o) =>
+          (o.companyName ?? "").toLowerCase().includes(q) ||
+          o.zitadelOrgId.toLowerCase().includes(q)
+      )
+    : orgs;
+
+  const choose = (o: OrgEntry) => {
+    onChange(o.zitadelOrgId);
+    setOpen(false);
+    setQuery("");
+  };
+
+  return (
+    <div ref={ref} className="relative">
+      <input
+        type="text"
+        value={open ? query : display}
+        onChange={(e) => {
+          setQuery(e.target.value);
+          setOpen(true);
+          setHi(0);
+        }}
+        onFocus={() => {
+          setOpen(true);
+          setQuery("");
+        }}
+        onKeyDown={(e) => {
+          if (e.key === "ArrowDown") {
+            e.preventDefault();
+            setOpen(true);
+            setHi((h) => Math.min(h + 1, filtered.length - 1));
+          } else if (e.key === "ArrowUp") {
+            e.preventDefault();
+            setHi((h) => Math.max(h - 1, 0));
+          } else if (e.key === "Enter") {
+            e.preventDefault();
+            if (open && filtered[hi]) choose(filtered[hi]);
+          } else if (e.key === "Escape") {
+            setOpen(false);
+          }
+        }}
+        placeholder={placeholder}
+        role="combobox"
+        aria-expanded={open}
+        aria-autocomplete="list"
+        className="w-full px-3 py-2 rounded-md border border-border bg-surface-2 text-sm text-text-primary placeholder:text-text-muted focus:outline-none focus:ring-1 focus:ring-accent focus:border-accent transition-colors"
+      />
+      {open && (
+        <ul
+          role="listbox"
+          className="absolute z-20 mt-1 max-h-64 w-full overflow-auto rounded-md border border-border bg-surface-1 shadow-xl py-1"
+        >
+          {filtered.length === 0 ? (
+            <li className="px-3 py-2 text-xs text-text-muted">
+              {noMatchesLabel}
+            </li>
+          ) : (
+            filtered.map((o, i) => (
+              <li
+                key={o.zitadelOrgId}
+                role="option"
+                aria-selected={o.zitadelOrgId === value}
+                onMouseEnter={() => setHi(i)}
+                // mousedown (not click) so selection runs before the
+                // input's blur closes the list.
+                onMouseDown={(e) => {
+                  e.preventDefault();
+                  choose(o);
+                }}
+                className={`px-3 py-2 text-sm cursor-pointer flex items-center justify-between gap-2 ${
+                  i === hi ? "bg-surface-3" : "hover:bg-surface-2"
+                }`}
+              >
+                <span className="truncate text-text-primary">
+                  {o.companyName ?? o.zitadelOrgId}
+                </span>
+                {!o.hasBillingAddress && (
+                  <span className="text-[10px] text-error shrink-0">
+                    {noBillingLabel}
+                  </span>
+                )}
+              </li>
+            ))
+          )}
+        </ul>
+      )}
+    </div>
+  );
+}