diff --git a/packages/web/src/api/client.ts b/packages/web/src/api/client.ts
index acb47ba6..8445bb75 100644
--- a/packages/web/src/api/client.ts
+++ b/packages/web/src/api/client.ts
@@ -277,6 +277,7 @@ export class BackspaceApiClient {
     peers: () => Promise<{ peers: FederationPeer[] }>;
     revokePeer: (id: string) => Promise<{ success: boolean }>;
     resetPeer: (id: string) => Promise<{ success: boolean }>;
+    recheckPeer: (id: string) => Promise<{ recovered: boolean; status: string }>;
     rotatePeerSecret: (id: string) => Promise<{ success: boolean; gracePeriodMs: number }>;
     updatePeer: (id: string, data: { autoRotateIntervalDays: number }) => Promise<{ peer: FederationPeer }>;
     deletePeerPermanently: (id: string) => Promise<{ success: boolean }>;
@@ -705,6 +706,8 @@ export class BackspaceApiClient {
         request<{ success: boolean }>('DELETE', `/federation/peers/${id}`),
       resetPeer: (id: string) =>
         request<{ success: boolean }>('POST', `/federation/peers/${id}/reset`),
+      recheckPeer: (id: string) =>
+        request<{ recovered: boolean; status: string }>('POST', `/federation/peers/${id}/recheck`),
       rotatePeerSecret: (id: string) =>
         request<{ success: boolean; gracePeriodMs: number }>('POST', `/federation/peers/${id}/rotate`),
       updatePeer: (id: string, data: { autoRotateIntervalDays: number }) =>
diff --git a/packages/web/src/components/modals/instanceSettingsPanels/FederationPanel.recheck.test.tsx b/packages/web/src/components/modals/instanceSettingsPanels/FederationPanel.recheck.test.tsx
new file mode 100644
index 00000000..5f2c0f46
--- /dev/null
+++ b/packages/web/src/components/modals/instanceSettingsPanels/FederationPanel.recheck.test.tsx
@@ -0,0 +1,48 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+import { render, screen, fireEvent, waitFor } from '@testing-library/react';
+
+const { recheckPeer, addToast } = vi.hoisted(() => ({
+  recheckPeer: vi.fn(),
+  addToast: vi.fn(),
+}));
+
+vi.mock('../../../api/client', () => ({
+  api: {
+    federation: {
+      peers: vi.fn().mockResolvedValue({ peers: [{
+        id: 'p1', origin: 'https://peer.example', instanceName: 'Peer',
+        status: 'unreachable', consecutiveFailures: 10, lastSeenAt: Date.now(),
+        autoRotateIntervalDays: 90, rotationInProgress: false,
+      }] }),
+      approvalRequests: vi.fn().mockResolvedValue({ requests: [] }),
+      recheckPeer,
+    },
+  },
+}));
+
+vi.mock('../../../stores/uiStore', () => ({
+  useUIStore: (sel: (s: { addToast: typeof addToast }) => unknown) => sel({ addToast }),
+}));
+
+vi.mock('../../../hooks/useWebSocket', () => ({
+  onFederationPeersChanged: () => () => {},
+}));
+
+import { FederationPanel } from './FederationPanel';
+
+describe('FederationPanel — Check now', () => {
+  beforeEach(() => { recheckPeer.mockReset(); addToast.mockReset(); });
+
+  it('shows Check now for an unreachable peer and recovers it on click', async () => {
+    recheckPeer.mockResolvedValue({ recovered: true, status: 'active' });
+    render(<FederationPanel />);
+    // PeerRow collapses its action buttons; expand the card by clicking its header first.
+    const header = await screen.findByText('Peer');
+    fireEvent.click(header);
+    const btn = await screen.findByText('Check now');
+    fireEvent.click(btn);
+    await waitFor(() => expect(recheckPeer).toHaveBeenCalledWith('p1'));
+    await waitFor(() => expect(addToast).toHaveBeenCalledWith(
+      expect.stringContaining('back online'), 'success', 3000));
+  });
+});
diff --git a/packages/web/src/components/modals/instanceSettingsPanels/FederationPanel.tsx b/packages/web/src/components/modals/instanceSettingsPanels/FederationPanel.tsx
index 1edfdaf4..6dcc04d3 100644
--- a/packages/web/src/components/modals/instanceSettingsPanels/FederationPanel.tsx
+++ b/packages/web/src/components/modals/instanceSettingsPanels/FederationPanel.tsx
@@ -388,12 +388,14 @@ function sortPeers(peers: FederationPeer[], sortBy: SortBy, view: PeerView): Fed
 
 // ─── Peer Row ────────────────────────────────────────────────────────────────
 
-function PeerRow({ peer, view, expanded, onToggleExpand, onAction, defaultAutoRotateIntervalDays }: {
+function PeerRow({ peer, view, expanded, onToggleExpand, onAction, onRecheck, recheckLoading, defaultAutoRotateIntervalDays }: {
   peer: FederationPeer;
   view: PeerView;
   expanded: boolean;
   onToggleExpand: () => void;
   onAction: (type: 'rotate' | 'revoke' | 'reinitiate' | 'delete' | 'reset') => void;
+  onRecheck: () => void;
+  recheckLoading: boolean;
   defaultAutoRotateIntervalDays: number;
 }) {
   const [editingInterval, setEditingInterval] = useState(false);
@@ -562,6 +564,16 @@ function PeerRow({ peer, view, expanded, onToggleExpand, onAction, defaultAutoRo
 
                 {/* Actions */}
                 <div className="flex items-center gap-2">
+                  {peer.status === 'unreachable' && (
+                    <button
+                      type="button"
+                      onClick={(e) => { e.stopPropagation(); onRecheck(); }}
+                      disabled={recheckLoading}
+                      className="px-3 py-1.5 text-xs font-medium bg-accent-mint/10 text-accent-mint hover:bg-accent-mint/20 rounded transition-colors disabled:opacity-50"
+                    >
+                      {recheckLoading ? 'Checking…' : 'Check now'}
+                    </button>
+                  )}
                   {peer.status === 'needs_attention' ? (
                     <button
                       type="button"
@@ -830,6 +842,7 @@ export function FederationPanel({ onApprovalCountChange }: { onApprovalCountChan
     peer: FederationPeer;
   } | null>(null);
   const [actionLoading, setActionLoading] = useState(false);
+  const [recheckingId, setRecheckingId] = useState<string | null>(null);
 
   const fetchPeers = useCallback(async () => {
     setPeersLoading(true);
@@ -879,6 +892,26 @@ export function FederationPanel({ onApprovalCountChange }: { onApprovalCountChan
         ? 'No revoked peers.'
         : null;
 
+  const handleRecheck = async (peer: FederationPeer) => {
+    setRecheckingId(peer.id);
+    try {
+      const result = await api.federation.recheckPeer(peer.id);
+      const name = peer.instanceName || new URL(peer.origin).host;
+      if (result.recovered) {
+        setPeers((prev) => prev.map((p) =>
+          p.id === peer.id ? { ...p, status: 'active' } : p
+        ));
+        addToast(`${name} is back online`, 'success', 3000);
+      } else {
+        addToast(`${name} is still unreachable`, 'warning', 3000);
+      }
+    } catch (err) {
+      addToast(err instanceof Error ? err.message : 'Recheck failed', 'warning', 3000);
+    } finally {
+      setRecheckingId(null);
+    }
+  };
+
   const handleConfirmAction = async () => {
     if (!confirmAction) return;
     const { type, peer } = confirmAction;
@@ -1032,6 +1065,8 @@ export function FederationPanel({ onApprovalCountChange }: { onApprovalCountChan
                   expanded={expandedPeerId === peer.id}
                   onToggleExpand={() => setExpandedPeerId(expandedPeerId === peer.id ? null : peer.id)}
                   onAction={(type) => setConfirmAction({ type, peer })}
+                  onRecheck={() => handleRecheck(peer)}
+                  recheckLoading={recheckingId === peer.id}
                   defaultAutoRotateIntervalDays={useSettingsStore.getState().instanceSettings?.defaultAutoRotateIntervalDays ?? 90}
                 />
               ))}