diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1541b60ffe2..6acc81624cc 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -67,6 +67,9 @@ Docs: https://docs.openclaw.ai
   itself for the current Gateway process after repeated failed restarts while
   the Gateway keeps running. Fixes #69011. Thanks @siddharthaagarwalofficial-ux,
   @FiredMosquito831, and @spikefcz.
+- Gateway/Fly.io: seed Control UI allowed origins from the actual runtime
+  bind and port so CLI-driven non-loopback starts do not crash before config
+  exists. Fixes #71823.
 - Feishu: accept Schema 2.0 card action callbacks that report
   `context.open_chat_id` instead of legacy `context.chat_id`, so button
   callbacks no longer drop as malformed. Fixes #71670. Thanks @eddy1068.
diff --git a/docs/gateway/index.md b/docs/gateway/index.md
index 446e2b67db0..8af2ee77c6e 100644
--- a/docs/gateway/index.md
+++ b/docs/gateway/index.md
@@ -112,6 +112,12 @@ All of these run on the main Gateway port and use the same trusted operator auth
 | Gateway port | `--port` → `OPENCLAW_GATEWAY_PORT` → `gateway.port` → `18789` |
 | Bind mode    | CLI/override → `gateway.bind` → `loopback`                    |
 
+Gateway startup uses the same effective port and bind when it seeds local
+Control UI origins for non-loopback binds. For example, `--bind lan --port 3000`
+seeds `http://localhost:3000` and `http://127.0.0.1:3000` before runtime
+validation runs. Add any remote browser origins, such as HTTPS proxy URLs, to
+`gateway.controlUi.allowedOrigins` explicitly.
+
 ### Hot reload modes
 
 | `gateway.reload.mode` | Behavior                                   |
diff --git a/docs/install/fly.md b/docs/install/fly.md
index c1b74dbcf2e..90fa72d18c6 100644
--- a/docs/install/fly.md
+++ b/docs/install/fly.md
@@ -193,7 +193,14 @@ read_when:
       },
       "gateway": {
         "mode": "local",
-        "bind": "auto"
+        "bind": "auto",
+        "controlUi": {
+          "allowedOrigins": [
+            "https://my-openclaw.fly.dev",
+            "http://localhost:3000",
+            "http://127.0.0.1:3000"
+          ]
+        }
       },
       "meta": {}
     }
@@ -202,6 +209,12 @@ read_when:
 
     **Note:** With `OPENCLAW_STATE_DIR=/data`, the config path is `/data/openclaw.json`.
 
+    **Note:** Replace `https://my-openclaw.fly.dev` with your real Fly app
+    origin. Gateway startup seeds local Control UI origins from the runtime
+    `--bind` and `--port` values so first boot can proceed before config exists,
+    but browser access through Fly still needs the exact HTTPS origin listed in
+    `gateway.controlUi.allowedOrigins`.
+
     **Note:** The Discord token can come from either:
 
     - Environment variable: `DISCORD_BOT_TOKEN` (recommended for secrets)
diff --git a/docs/web/control-ui.md b/docs/web/control-ui.md
index 8c98a69808f..2e8d9ab6062 100644
--- a/docs/web/control-ui.md
+++ b/docs/web/control-ui.md
@@ -437,6 +437,9 @@ Notes:
 - `gatewayUrl` is only accepted in a top-level window (not embedded) to prevent clickjacking.
 - Non-loopback Control UI deployments must set `gateway.controlUi.allowedOrigins`
   explicitly (full origins). This includes remote dev setups.
+- Gateway startup may seed local origins such as `http://localhost:<port>` and
+  `http://127.0.0.1:<port>` from the effective runtime bind and port, but remote
+  browser origins still need explicit entries.
 - Do not use `gateway.controlUi.allowedOrigins: ["*"]` except for tightly controlled
   local testing. It means allow any browser origin, not “match whatever host I am
   using.”
diff --git a/src/config/gateway-control-ui-origins.test.ts b/src/config/gateway-control-ui-origins.test.ts
new file mode 100644
index 00000000000..f8172c7a410
--- /dev/null
+++ b/src/config/gateway-control-ui-origins.test.ts
@@ -0,0 +1,88 @@
+import { describe, expect, it } from "vitest";
+import { ensureControlUiAllowedOriginsForNonLoopbackBind } from "./gateway-control-ui-origins.js";
+
+describe("ensureControlUiAllowedOriginsForNonLoopbackBind", () => {
+  it("seeds Fly-style runtime bind and port when config is empty", () => {
+    const result = ensureControlUiAllowedOriginsForNonLoopbackBind(
+      { gateway: {} },
+      {
+        runtimeBind: "lan",
+        runtimePort: 3000,
+        isContainerEnvironment: () => false,
+      },
+    );
+
+    expect(result.bind).toBe("lan");
+    expect(result.seededOrigins).toEqual(["http://localhost:3000", "http://127.0.0.1:3000"]);
+    expect(result.config.gateway?.controlUi?.allowedOrigins).toEqual(result.seededOrigins);
+  });
+
+  it("uses runtime bind before config bind to match gateway startup precedence", () => {
+    const result = ensureControlUiAllowedOriginsForNonLoopbackBind(
+      { gateway: { bind: "loopback" } },
+      {
+        runtimeBind: "lan",
+        isContainerEnvironment: () => false,
+      },
+    );
+
+    expect(result.bind).toBe("lan");
+    expect(result.seededOrigins).not.toBeNull();
+  });
+
+  it("uses runtime loopback before config non-loopback and avoids seeding", () => {
+    const result = ensureControlUiAllowedOriginsForNonLoopbackBind(
+      { gateway: { bind: "lan" } },
+      {
+        runtimeBind: "loopback",
+        isContainerEnvironment: () => false,
+      },
+    );
+
+    expect(result.bind).toBeNull();
+    expect(result.seededOrigins).toBeNull();
+  });
+
+  it("uses runtime port before config port to match gateway startup precedence", () => {
+    const result = ensureControlUiAllowedOriginsForNonLoopbackBind(
+      { gateway: { bind: "lan", port: 18789 } },
+      {
+        runtimePort: 3000,
+        isContainerEnvironment: () => false,
+      },
+    );
+
+    expect(result.seededOrigins).toEqual(["http://localhost:3000", "http://127.0.0.1:3000"]);
+  });
+
+  it("keeps container fallback when runtime and config bind are unset", () => {
+    const result = ensureControlUiAllowedOriginsForNonLoopbackBind(
+      { gateway: {} },
+      { isContainerEnvironment: () => true },
+    );
+
+    expect(result.bind).toBe("auto");
+    expect(result.seededOrigins).toEqual(["http://localhost:18789", "http://127.0.0.1:18789"]);
+  });
+
+  it("does not overwrite explicit allowed origins", () => {
+    const result = ensureControlUiAllowedOriginsForNonLoopbackBind(
+      {
+        gateway: {
+          controlUi: { allowedOrigins: ["https://control.example.com"] },
+        },
+      },
+      {
+        runtimeBind: "lan",
+        runtimePort: 3000,
+        isContainerEnvironment: () => false,
+      },
+    );
+
+    expect(result.bind).toBe("lan");
+    expect(result.seededOrigins).toBeNull();
+    expect(result.config.gateway?.controlUi?.allowedOrigins).toEqual([
+      "https://control.example.com",
+    ]);
+  });
+});
diff --git a/src/config/gateway-control-ui-origins.ts b/src/config/gateway-control-ui-origins.ts
index e1c91752750..40bfb32122c 100644
--- a/src/config/gateway-control-ui-origins.ts
+++ b/src/config/gateway-control-ui-origins.ts
@@ -48,6 +48,12 @@ export function ensureControlUiAllowedOriginsForNonLoopbackBind(
   opts?: {
     defaultPort?: number;
     requireControlUiEnabled?: boolean;
+    /** Resolved runtime bind override. Mirrors Gateway runtime precedence:
+     *  explicit CLI/runtime bind wins over gateway.bind. */
+    runtimeBind?: unknown;
+    /** Resolved runtime port override. Mirrors Gateway runtime precedence:
+     *  explicit CLI/runtime port wins over gateway.port. */
+    runtimePort?: unknown;
     /** Optional container-detection callback.  When provided and `gateway.bind`
      *  is unset, the function is called to determine whether the runtime will
      *  default to `"auto"` (container) so that origins can be seeded
@@ -60,7 +66,7 @@ export function ensureControlUiAllowedOriginsForNonLoopbackBind(
   seededOrigins: string[] | null;
   bind: GatewayNonLoopbackBindMode | null;
 } {
-  const bind = config.gateway?.bind;
+  const bind = opts?.runtimeBind ?? config.gateway?.bind;
   // When bind is unset (undefined) and we are inside a container, the runtime
   // will default to "auto" → 0.0.0.0 via defaultGatewayBindMode().  We must
   // seed origins *before* resolveGatewayRuntimeConfig runs, otherwise the
@@ -83,7 +89,10 @@ export function ensureControlUiAllowedOriginsForNonLoopbackBind(
     return { config, seededOrigins: null, bind: effectiveBind };
   }
 
-  const port = resolveGatewayPortWithDefault(config.gateway?.port, opts?.defaultPort);
+  const port = resolveGatewayPortWithDefault(
+    opts?.runtimePort ?? config.gateway?.port,
+    opts?.defaultPort,
+  );
   const seededOrigins = buildDefaultControlUiAllowedOrigins({
     port,
     bind: effectiveBind,
diff --git a/src/gateway/server.impl.ts b/src/gateway/server.impl.ts
index f335dafb680..a59b9b8e1a7 100644
--- a/src/gateway/server.impl.ts
+++ b/src/gateway/server.impl.ts
@@ -328,6 +328,8 @@ export async function startGatewayServer(
           config: cfgAtStart,
           writeConfig: writeConfigFile,
           log,
+          runtimeBind: opts.bind,
+          runtimePort: port,
         }),
       );
   cfgAtStart = controlUiSeed.config;
diff --git a/src/gateway/startup-control-ui-origins.test.ts b/src/gateway/startup-control-ui-origins.test.ts
new file mode 100644
index 00000000000..4e8e7d6bfe8
--- /dev/null
+++ b/src/gateway/startup-control-ui-origins.test.ts
@@ -0,0 +1,51 @@
+import { describe, expect, it, vi } from "vitest";
+import type { OpenClawConfig } from "../config/types.openclaw.js";
+import { maybeSeedControlUiAllowedOriginsAtStartup } from "./startup-control-ui-origins.js";
+
+describe("maybeSeedControlUiAllowedOriginsAtStartup", () => {
+  it("persists origins seeded from runtime bind and port", async () => {
+    const written: OpenClawConfig[] = [];
+    const log = { info: vi.fn(), warn: vi.fn() };
+
+    const result = await maybeSeedControlUiAllowedOriginsAtStartup({
+      config: { gateway: {} },
+      writeConfig: async (config) => {
+        written.push(config);
+      },
+      log,
+      runtimeBind: "lan",
+      runtimePort: 3000,
+    });
+
+    const expectedOrigins = ["http://localhost:3000", "http://127.0.0.1:3000"];
+    expect(result.persistedAllowedOriginsSeed).toBe(true);
+    expect(result.config.gateway?.controlUi?.allowedOrigins).toEqual(expectedOrigins);
+    expect(written).toHaveLength(1);
+    expect(written[0]?.gateway?.controlUi?.allowedOrigins).toEqual(expectedOrigins);
+    expect(log.info).toHaveBeenCalledWith(expect.stringContaining("for bind=lan"));
+    expect(log.warn).not.toHaveBeenCalled();
+  });
+
+  it("does not rewrite config when origins already exist", async () => {
+    const config: OpenClawConfig = {
+      gateway: {
+        controlUi: { allowedOrigins: ["https://control.example.com"] },
+      },
+    };
+    const writeConfig = vi.fn<() => Promise<void>>();
+    const log = { info: vi.fn(), warn: vi.fn() };
+
+    const result = await maybeSeedControlUiAllowedOriginsAtStartup({
+      config,
+      writeConfig,
+      log,
+      runtimeBind: "lan",
+      runtimePort: 3000,
+    });
+
+    expect(result).toEqual({ config, persistedAllowedOriginsSeed: false });
+    expect(writeConfig).not.toHaveBeenCalled();
+    expect(log.info).not.toHaveBeenCalled();
+    expect(log.warn).not.toHaveBeenCalled();
+  });
+});
diff --git a/src/gateway/startup-control-ui-origins.ts b/src/gateway/startup-control-ui-origins.ts
index 698c50f92bd..fc030f0a1cc 100644
--- a/src/gateway/startup-control-ui-origins.ts
+++ b/src/gateway/startup-control-ui-origins.ts
@@ -9,9 +9,13 @@ export async function maybeSeedControlUiAllowedOriginsAtStartup(params: {
   config: OpenClawConfig;
   writeConfig: (config: OpenClawConfig) => Promise<void>;
   log: { info: (msg: string) => void; warn: (msg: string) => void };
+  runtimeBind?: unknown;
+  runtimePort?: unknown;
 }): Promise<{ config: OpenClawConfig; persistedAllowedOriginsSeed: boolean }> {
   const seeded = ensureControlUiAllowedOriginsForNonLoopbackBind(params.config, {
     isContainerEnvironment,
+    runtimeBind: params.runtimeBind,
+    runtimePort: params.runtimePort,
   });
   if (!seeded.seededOrigins || !seeded.bind) {
     return { config: params.config, persistedAllowedOriginsSeed: false };