diff --git a/.gitea/workflows/server-deploy.yml b/.gitea/workflows/server-deploy.yml
index 350291b..64d1907 100644
--- a/.gitea/workflows/server-deploy.yml
+++ b/.gitea/workflows/server-deploy.yml
@@ -150,6 +150,7 @@ jobs:
                     --build-arg NEXT_PUBLIC_ADMIN_ENV="${{ vars.ADMIN_ENV }}" \
                     --build-arg NEXT_PUBLIC_PADDLE_CLIENT_TOKEN="${{ vars.PADDLE_CLIENT_TOKEN }}" \
                     --build-arg NEXT_PUBLIC_PADDLE_ENV="${{ vars.PADDLE_ENV }}" \
+                    --build-arg NEXT_PUBLIC_SITE_URL="${{ vars.SITE_URL }}" \
                     -t "$IMAGE" \
                     -f adminsite/Dockerfile adminsite/
                   docker push "$IMAGE"
diff --git a/adminsite/Dockerfile b/adminsite/Dockerfile
index 1b38eee..b0acc44 100644
--- a/adminsite/Dockerfile
+++ b/adminsite/Dockerfile
@@ -26,6 +26,11 @@ ENV NEXT_PUBLIC_PADDLE_CLIENT_TOKEN=$NEXT_PUBLIC_PADDLE_CLIENT_TOKEN
 ARG NEXT_PUBLIC_PADDLE_ENV=sandbox
 ENV NEXT_PUBLIC_PADDLE_ENV=$NEXT_PUBLIC_PADDLE_ENV
 
+# Marketing site origin. Signup lives there (/start), not here; empty renders no
+# link at all rather than one that 404s.
+ARG NEXT_PUBLIC_SITE_URL=
+ENV NEXT_PUBLIC_SITE_URL=$NEXT_PUBLIC_SITE_URL
+
 RUN npm run build
 
 FROM node:26-alpine AS runner
diff --git a/adminsite/app/layout.tsx b/adminsite/app/layout.tsx
index 848c6f9..b195ee9 100644
--- a/adminsite/app/layout.tsx
+++ b/adminsite/app/layout.tsx
@@ -10,7 +10,7 @@ export const metadata: Metadata = {
 
 /*
  * The masthead deliberately does NOT live here. It belongs to the authenticated
- * layouts, so /login, /signup, /verify and /accept-invite stop rendering a bar
+ * layouts, so /login, /verify and /accept-invite stop rendering a bar
  * whose navigation and account menu they cannot use.
  */
 export default function RootLayout({ children }: { children: React.ReactNode }) {
diff --git a/adminsite/app/login/page.tsx b/adminsite/app/login/page.tsx
index ed18e08..2ed74aa 100644
--- a/adminsite/app/login/page.tsx
+++ b/adminsite/app/login/page.tsx
@@ -2,12 +2,13 @@
 
 import { useRouter } from "next/navigation";
 import { useState } from "react";
-import Link from "next/link";
 import { API_BASE, ApiError, NotConnected, api } from "@/lib/api";
 import { NotConnectedPanel } from "@/components/NotConnected";
 import { Button } from "@/components/Button";
 import { Field } from "@/components/Field";
 
+const SITE_URL = (process.env.NEXT_PUBLIC_SITE_URL ?? "").replace(/\/$/, "");
+
 export default function LoginPage() {
     const router = useRouter();
     const [email, setEmail] = useState("");
@@ -91,14 +92,19 @@ export default function LoginPage() {
                     </Button>
                 </form>
 
-                <div className="my-5 h-px bg-rule-soft" />
+                {SITE_URL && (
+                    <>
+                        <div className="my-5 h-px bg-rule-soft" />
 
-                <p className="text-center text-[0.82rem] text-ink-3">
-                    No account?{" "}
-                    <Link href="/signup" className="text-accent underline">
-                        Create one for a self-hosted licence
-                    </Link>
-                </p>
+                        {/* Signup lives on the marketing site's /start, not here. */}
+                        <p className="text-center text-[0.82rem] text-ink-3">
+                            No account?{" "}
+                            <a href={`${SITE_URL}/start`} className="text-accent underline">
+                                Create one
+                            </a>
+                        </p>
+                    </>
+                )}
             </div>
         </Main>
     );
diff --git a/adminsite/app/signup/page.tsx b/adminsite/app/signup/page.tsx
deleted file mode 100644
index 7761171..0000000
--- a/adminsite/app/signup/page.tsx
+++ /dev/null
@@ -1,92 +0,0 @@
-"use client";
-
-import { useState } from "react";
-import { ApiError, NotConnected, api } from "@/lib/api";
-import { Button } from "@/components/Button";
-import { Field } from "@/components/Field";
-
-export default function SignupPage() {
-    const [form, setForm] = useState({ name: "", email: "", password: "", website: "" });
-    const [state, setState] = useState<"idle" | "busy" | "sent">("idle");
-    const [error, setError] = useState<string | null>(null);
-
-    async function submit(e: React.FormEvent) {
-        e.preventDefault();
-        setState("busy");
-        setError(null);
-        try {
-            await api.signup(form);
-            setState("sent");
-        } catch (err) {
-            setState("idle");
-            setError(
-                err instanceof NotConnected
-                    ? "The licensing service is not reachable from this page."
-                    : err instanceof ApiError
-                      ? err.message
-                      : "Could not create the account. Try again.",
-            );
-        }
-    }
-
-    return (
-        <main className="mx-auto max-w-rail px-5 py-12">
-            {state === "sent" ? (
-                <div className="grid max-w-xl gap-3">
-                    <h1 className="text-3xl">Check your email</h1>
-                    <p className="text-ink-2">
-                        We sent a link to {form.email}. Open it to finish setting up your account —
-                        it expires in 24 hours. Nothing is created until you do.
-                    </p>
-                </div>
-            ) : (
-                <>
-                    <h1 className="text-3xl">Create an account</h1>
-                    <p className="mt-2 max-w-xl text-ink-2">
-                        For self-hosted licences. If you run on our cloud, sign in with the same
-                        details you use for your Vantage instance.
-                    </p>
-                    <form onSubmit={submit} className="mt-6 grid gap-4">
-                        <Field
-                            label="Organisation"
-                            required
-                            value={form.name}
-                            onChange={(e) => setForm({ ...form, name: e.target.value })}
-                        />
-                        <Field
-                            label="Email"
-                            type="email"
-                            required
-                            value={form.email}
-                            onChange={(e) => setForm({ ...form, email: e.target.value })}
-                        />
-                        <Field
-                            label="Password"
-                            type="password"
-                            required
-                            minLength={12}
-                            hint="At least 12 characters."
-                            value={form.password}
-                            onChange={(e) => setForm({ ...form, password: e.target.value })}
-                            error={error ?? undefined}
-                        />
-                        {/* Honeypot: off-screen, unlabelled for humans, irresistible to bots. */}
-                        <input
-                            type="text"
-                            name="website"
-                            tabIndex={-1}
-                            autoComplete="off"
-                            aria-hidden="true"
-                            value={form.website}
-                            onChange={(e) => setForm({ ...form, website: e.target.value })}
-                            className="absolute left-[-9999px] h-0 w-0"
-                        />
-                        <Button type="submit" disabled={state === "busy"}>
-                            {state === "busy" ? "Creating…" : "Create account"}
-                        </Button>
-                    </form>
-                </>
-            )}
-        </main>
-    );
-}
diff --git a/adminsite/lib/api.ts b/adminsite/lib/api.ts
index 0a89e31..dff5f18 100644
--- a/adminsite/lib/api.ts
+++ b/adminsite/lib/api.ts
@@ -296,8 +296,6 @@ export const api = {
     staffLogin: (email: string, password: string) =>
         post<Session>("/auth/staff/login", { email, password }),
     logout: () => post<{ ok: boolean }>("/auth/logout"),
-    signup: (payload: { name: string; email: string; password: string; website?: string }) =>
-        post<{ pending: boolean }>("/auth/signup", payload),
     verify: (token: string) =>
         req<{ verified: boolean; needs_password?: boolean }>(
             `/auth/verify?token=${encodeURIComponent(token)}`,
diff --git a/claude.md b/claude.md
index 16a0d79..36a5f20 100644
--- a/claude.md
+++ b/claude.md
@@ -669,6 +669,7 @@ git push origin main                                    # server + web deploy
 | `API_URL`               | **not** a CI variable | `web` reads it at **runtime**, from the container environment — `next.config.ts` is evaluated when `server.js` boots in standalone mode, and the rewrites it feeds are server-side, never browser-side. Default `http://localhost:8080`; compose sets `http://server:8080`. `NEXT_PUBLIC_API_URL` is still honoured as a fallback for existing deployments. |
 | `SITE_API_URL`          | Variable | **browser-reachable** sitesvc URL, baked into the `site` image. Required — if empty, both forms report "not connected" and submit nowhere. Must also be in sitesvc's `SITE_ORIGIN`.                                                                        |
 | `SITE_CONTACT_EMAIL`    | Variable | optional; address shown when a form is misconfigured                                                                                                                                                                                                       |
+| `SITE_URL`              | Variable | browser URL of the marketing site, baked into `adminsite` so `/login` can point at `/start`. **Signup has no page in `adminsite` at all** — one signup form, on `site/`. Empty renders no link rather than one that 404s.                                  |
 | `ADMIN_API_URL`         | Variable | **browser-reachable** admin URL, baked into **both** the `adminsite` and `site` images — `site/start` posts account signups straight to admin. Same footgun as `SITE_API_URL`: wrong here and every request fails at runtime with the not-connected panel. |
 | `ADMIN_ENV`             | Variable | `production` or `sandbox`; drives the persistent environment badge. Anything but `sandbox` reads as production.                                                                                                                                            |
 | `HQ_URL`                | Variable | optional; browser URL of the HQ portal, baked into `web` so an `hq`-sourced member links to where they are managed. Empty on self-hosted, which renders a plain label instead.                                                                             |