diff --git a/desktop/src/app/App.tsx b/desktop/src/app/App.tsx
index a4b44d2974..0fe740ebc3 100644
--- a/desktop/src/app/App.tsx
+++ b/desktop/src/app/App.tsx
@@ -39,6 +39,7 @@ import { WelcomeSetup } from "@/features/communities/ui/WelcomeSetup";
 import { CommunityApplyErrorScreen } from "@/features/communities/ui/CommunityApplyErrorScreen";
 import { CommunityChangeOverlay } from "@/features/communities/ui/CommunityChangeOverlay";
 import { createBuzzQueryClient } from "@/shared/api/queryClient";
+import { getMyRelayMembershipLookup } from "@/shared/api/relayMembers";
 import { isSharedIdentity as isSharedIdentityCmd } from "@/shared/api/tauri";
 import {
   type AddCommunityDeepLinkPayload,
@@ -61,6 +62,16 @@ const BOOT_SPLASH_MIN_VISIBLE_MS = 1_200;
 const BOOT_SPLASH_FADE_MS = 200;
 const INITIAL_RENDER_READY_EVENT = "initial-render-ready";
 
+function isRelayMembershipDeniedError(error: unknown): boolean {
+  if (!(error instanceof Error)) return false;
+  return [
+    "You must be a relay member",
+    "relay_membership_required",
+    "restricted: not a relay member",
+    "invalid: you are not a relay member",
+  ].some((message) => error.message.includes(message));
+}
+
 type BootSplashPhase = "holding" | "fading" | "done";
 
 function useInitialRenderReady() {
@@ -325,10 +336,45 @@ function CommunityApp({
     community.isReady &&
     community.appliedKey === communityKey;
   useEffect(() => {
-    if (transaction?.stage === "connecting" && targetIsReady) {
-      communityOnboarding.update({ stage: "profile", error: undefined });
+    if (
+      transaction?.stage !== "connecting" ||
+      transaction.error ||
+      !targetIsReady
+    ) {
+      return;
     }
-  }, [communityOnboarding.update, targetIsReady, transaction?.stage]);
+
+    let cancelled = false;
+    void getMyRelayMembershipLookup()
+      .then(({ membership, snapshotFound }) => {
+        if (cancelled) return;
+        if (snapshotFound && membership === null) {
+          communityOnboarding.update({
+            error:
+              "You have not been added to this community yet. Ask the host to add your public key, then try again.",
+          });
+          return;
+        }
+        communityOnboarding.update({ stage: "profile", error: undefined });
+      })
+      .catch((error: unknown) => {
+        if (cancelled) return;
+        communityOnboarding.update({
+          error: isRelayMembershipDeniedError(error)
+            ? "You have not been added to this community yet. Ask the host to add your public key, then try again."
+            : "Could not check community access. Check the URL and try again.",
+        });
+      });
+
+    return () => {
+      cancelled = true;
+    };
+  }, [
+    communityOnboarding.update,
+    targetIsReady,
+    transaction?.error,
+    transaction?.stage,
+  ]);
   // During "entering" the transaction stays alive as a curtain: the app mounts
   // underneath (already pointed at the Welcome channel route) while the
   // onboarding screen covers it, then fades once Welcome reports ready.
diff --git a/desktop/src/features/communities/ui/WelcomeSetup.tsx b/desktop/src/features/communities/ui/WelcomeSetup.tsx
index c4412bd2d9..7c4dbdaaec 100644
--- a/desktop/src/features/communities/ui/WelcomeSetup.tsx
+++ b/desktop/src/features/communities/ui/WelcomeSetup.tsx
@@ -3,6 +3,7 @@ import { openUrl } from "@tauri-apps/plugin-opener";
 import { Check, Copy, Info } from "lucide-react";
 
 import { useCommunityOnboarding } from "@/features/onboarding/communityOnboarding";
+import { normalizeRelayUrl } from "@/features/communities/relayProbe";
 import { InviteRedeemForm } from "@/features/onboarding/ui/InviteRedeemForm";
 import {
   ONBOARDING_KEY_FRAME_CLASS,
@@ -20,6 +21,7 @@ import {
 import { getIdentity } from "@/shared/api/tauriIdentity";
 import { pubkeyToNpub } from "@/shared/lib/nostrUtils";
 import { Button } from "@/shared/ui/button";
+import { Input } from "@/shared/ui/input";
 import { StartupWindowDragRegion } from "@/shared/ui/StartupWindowDragRegion";
 import { useSystemColorScheme } from "@/shared/theme/useSystemColorScheme";
 import { OnboardingChrome } from "@/features/onboarding/ui/OnboardingChrome";
@@ -56,6 +58,8 @@ export function WelcomeSetup({
     React.useState<WelcomeTransitionMode>(initialTransitionMode);
   const [npub, setNpub] = React.useState("");
   const [identityError, setIdentityError] = React.useState<string | null>(null);
+  const [relayUrl, setRelayUrl] = React.useState("");
+  const [relayUrlError, setRelayUrlError] = React.useState<string | null>(null);
   const [copied, setCopied] = React.useState(false);
   const communityOnboarding = useCommunityOnboarding();
   const systemColorScheme = useSystemColorScheme();
@@ -79,6 +83,24 @@ export function WelcomeSetup({
     setPage(nextPage);
   }, []);
 
+  const handleJoin = React.useCallback(
+    (event: React.FormEvent) => {
+      event.preventDefault();
+      const normalizedRelayUrl = normalizeRelayUrl(relayUrl);
+      if (!normalizedRelayUrl) {
+        setRelayUrlError("Enter a valid community URL.");
+        return;
+      }
+
+      setRelayUrlError(null);
+      communityOnboarding.start({
+        source: "first-community",
+        relayUrl: normalizedRelayUrl,
+      });
+    },
+    [communityOnboarding, relayUrl],
+  );
+
   const handleInviteRedeem = React.useCallback(
     (relayWsUrl: string, code: string, policyReceipt?: string) => {
       communityOnboarding.start({
@@ -172,58 +194,106 @@ export function WelcomeSetup({
                 </p>
               </div>
               <div className="flex w-full flex-1 items-center justify-center pb-4 pt-12">
-                <div className="w-full max-w-4xl">
-                  <div
-                    className={ONBOARDING_KEY_FRAME_CLASS}
-                    data-testid="welcome-join-npub-frame"
+                <div className="w-full max-w-4xl space-y-7">
+                  <div>
+                    <div
+                      className={ONBOARDING_KEY_FRAME_CLASS}
+                      data-testid="welcome-join-npub-frame"
+                    >
+                      <div className={ONBOARDING_KEY_ROW_CLASS}>
+                        <div className="min-w-0 flex-1">
+                          <code
+                            className={`${ONBOARDING_KEY_TEXT_CLASS} block`}
+                            data-testid="welcome-join-npub"
+                          >
+                            {npub || "Loading…"}
+                          </code>
+                        </div>
+                        <Button
+                          aria-label="Copy npub"
+                          className="h-10 w-10 shrink-0 text-muted-foreground hover:text-foreground"
+                          disabled={!npub}
+                          onClick={() => {
+                            void writeTextToClipboard(npub).then(() => {
+                              setCopied(true);
+                              window.setTimeout(() => setCopied(false), 1500);
+                            });
+                          }}
+                          size="icon"
+                          type="button"
+                          variant="ghost"
+                        >
+                          {copied ? (
+                            <Check
+                              className="h-6 w-6 text-primary"
+                              aria-hidden="true"
+                            />
+                          ) : (
+                            <Copy className="h-6 w-6" aria-hidden="true" />
+                          )}
+                        </Button>
+                      </div>
+                    </div>
+                    {identityError ? (
+                      <p className="mt-4 text-sm text-destructive">
+                        {identityError}
+                      </p>
+                    ) : (
+                      <p className="mx-auto mt-4 flex max-w-[440px] items-start justify-center gap-1.5 text-center text-xs leading-5 text-[var(--buzz-onboarding-backup-ink)]">
+                        <Info className="mt-0.5 h-3.5 w-3.5 shrink-0" />
+                        <span>
+                          This is safe to share. It does not reveal your private
+                          key.
+                        </span>
+                      </p>
+                    )}
+                  </div>
+                  <form
+                    className="mx-auto w-full max-w-[680px] text-left"
+                    onSubmit={handleJoin}
                   >
-                    <div className={ONBOARDING_KEY_ROW_CLASS}>
+                    <label
+                      className="text-sm font-medium"
+                      htmlFor="welcome-join-community-url"
+                    >
+                      Community URL
+                    </label>
+                    <div className="mt-2 flex items-start gap-3">
                       <div className="min-w-0 flex-1">
-                        <code
-                          className={`${ONBOARDING_KEY_TEXT_CLASS} block`}
-                          data-testid="welcome-join-npub"
-                        >
-                          {npub || "Loading…"}
-                        </code>
+                        <Input
+                          autoCapitalize="none"
+                          autoCorrect="off"
+                          data-testid="welcome-join-community-url"
+                          id="welcome-join-community-url"
+                          onChange={(event) => {
+                            setRelayUrl(event.target.value);
+                            setRelayUrlError(null);
+                          }}
+                          placeholder="https://community.example.com"
+                          spellCheck={false}
+                          type="url"
+                          value={relayUrl}
+                        />
+                        {relayUrlError ? (
+                          <p className="mt-2 text-sm text-destructive">
+                            {relayUrlError}
+                          </p>
+                        ) : (
+                          <p className="mt-2 text-xs leading-5 text-foreground/70">
+                            Once the host adds your public key, enter the URL to
+                            join. You can retry if access is not ready yet.
+                          </p>
+                        )}
                       </div>
                       <Button
-                        aria-label="Copy npub"
-                        className="h-10 w-10 shrink-0 text-muted-foreground hover:text-foreground"
-                        disabled={!npub}
-                        onClick={() => {
-                          void writeTextToClipboard(npub).then(() => {
-                            setCopied(true);
-                            window.setTimeout(() => setCopied(false), 1500);
-                          });
-                        }}
-                        size="icon"
-                        type="button"
-                        variant="ghost"
+                        className="h-10 shrink-0 rounded-full px-6"
+                        disabled={!relayUrl.trim()}
+                        type="submit"
                       >
-                        {copied ? (
-                          <Check
-                            className="h-6 w-6 text-primary"
-                            aria-hidden="true"
-                          />
-                        ) : (
-                          <Copy className="h-6 w-6" aria-hidden="true" />
-                        )}
+                        Join community
                       </Button>
                     </div>
-                  </div>
-                  {identityError ? (
-                    <p className="mt-4 text-sm text-destructive">
-                      {identityError}
-                    </p>
-                  ) : (
-                    <p className="mx-auto mt-6 flex max-w-[440px] items-start justify-center gap-1.5 text-center text-xs leading-5 text-[var(--buzz-onboarding-backup-ink)]">
-                      <Info className="mt-0.5 h-3.5 w-3.5 shrink-0" />
-                      <span>
-                        This is safe to share. It does not reveal your private
-                        key.
-                      </span>
-                    </p>
-                  )}
+                  </form>
                 </div>
               </div>
               <OnboardingFooter>
diff --git a/desktop/src/features/onboarding/ui/CommunityOnboardingFlow.tsx b/desktop/src/features/onboarding/ui/CommunityOnboardingFlow.tsx
index e4f8459728..fee7cd6788 100644
--- a/desktop/src/features/onboarding/ui/CommunityOnboardingFlow.tsx
+++ b/desktop/src/features/onboarding/ui/CommunityOnboardingFlow.tsx
@@ -172,7 +172,11 @@ export function CommunityOnboardingFlow({
     };
   }, [clear, isEnteringStage]);
 
-  const retryClaim = () => update({ stage: "claiming", error: undefined });
+  const retry = () =>
+    update({
+      stage: transaction?.inviteCode ? "claiming" : "connecting",
+      error: undefined,
+    });
   const relayUrl = transaction?.relayUrl;
   const finish = React.useCallback(async () => {
     if (!relayUrl) return;
@@ -295,7 +299,7 @@ export function CommunityOnboardingFlow({
               </p>
               <div className="mt-6 flex justify-center gap-3">
                 {transaction.error ? (
-                  <Button className="rounded-full px-6" onClick={retryClaim}>
+                  <Button className="rounded-full px-6" onClick={retry}>
                     Retry
                   </Button>
                 ) : null}