diff --git a/components/organization/bounties/manage/BountyManagementDashboard.tsx b/components/organization/bounties/manage/BountyManagementDashboard.tsx
index 09f792d3..448ec9f5 100644
--- a/components/organization/bounties/manage/BountyManagementDashboard.tsx
+++ b/components/organization/bounties/manage/BountyManagementDashboard.tsx
@@ -3,7 +3,7 @@
 import { useState } from 'react';
 import { useParams } from 'next/navigation';
 import Link from 'next/link';
-import { ArrowLeft, Info, Loader2, Lock } from 'lucide-react';
+import { ArrowLeft, Info, Loader2 } from 'lucide-react';
 
 import { Badge } from '@/components/ui/badge';
 import { Tabs, TabsContent, TabsList, TabsTrigger } from '@/components/ui/tabs';
@@ -27,6 +27,7 @@ import { ordinal } from '@/lib/utils';
 import BountySubmissionsPanel from './BountySubmissionsPanel';
 import BountyPayoutPanel from './BountyPayoutPanel';
 import BountyApplicationsPanel from './BountyApplicationsPanel';
+import BountySettingsPanel from './BountySettingsPanel';
 
 export default function BountyManagementDashboard() {
   const params = useParams<{ id: string; bountyId: string }>();
@@ -183,7 +184,11 @@ export default function BountyManagementDashboard() {
           />
         </TabsContent>
         <TabsContent value='settings'>
-          <TabPlaceholder title='Settings & cancel / refund' issue='#634' />
+          <BountySettingsPanel
+            organizationId={organizationId}
+            bountyId={bountyId}
+            overview={overview}
+          />
         </TabsContent>
       </Tabs>
     </div>
@@ -354,13 +359,3 @@ function Row({
     </div>
   );
 }
-
-function TabPlaceholder({ title, issue }: { title: string; issue: string }) {
-  return (
-    <div className='rounded-2xl border border-dashed border-zinc-800 bg-zinc-900/20 py-16 text-center'>
-      <Lock className='mx-auto mb-3 h-5 w-5 text-zinc-600' />
-      <p className='text-sm font-medium text-zinc-300'>{title}</p>
-      <p className='mt-1 text-xs text-zinc-600'>Coming soon ({issue}).</p>
-    </div>
-  );
-}
diff --git a/components/organization/bounties/manage/BountySettingsPanel.tsx b/components/organization/bounties/manage/BountySettingsPanel.tsx
new file mode 100644
index 00000000..8d1c8c62
--- /dev/null
+++ b/components/organization/bounties/manage/BountySettingsPanel.tsx
@@ -0,0 +1,177 @@
+'use client';
+
+import { useState } from 'react';
+import {
+  AlertTriangle,
+  CheckCircle2,
+  ExternalLink,
+  Loader2,
+} from 'lucide-react';
+
+import {
+  Dialog,
+  DialogContent,
+  DialogDescription,
+  DialogFooter,
+  DialogHeader,
+  DialogTitle,
+} from '@/components/ui/dialog';
+import { Input } from '@/components/ui/input';
+import { BoundlessButton } from '@/components/buttons';
+import {
+  ESCROW_PHASE_LABEL,
+  type BountyOperateOverview,
+} from '@/features/bounties';
+import { useBountyCancel } from '@/hooks/use-bounty-cancel';
+import { getTransactionExplorerUrl } from '@/lib/wallet-utils';
+
+const PHASE_LABEL = {
+  ...ESCROW_PHASE_LABEL,
+  starting: 'Preparing cancellation…',
+  polling: 'Refunding escrow on-chain…',
+};
+
+/** Lifecycle statuses that mean the bounty can no longer be cancelled. */
+const TERMINAL_STATUSES = new Set(['completed', 'cancelled']);
+
+const CONFIRM_PHRASE = 'CANCEL';
+
+export default function BountySettingsPanel({
+  organizationId,
+  bountyId,
+  overview,
+}: {
+  organizationId: string;
+  bountyId: string;
+  overview: BountyOperateOverview;
+}) {
+  const cancelOp = useBountyCancel({ organizationId, bountyId });
+  const [confirmOpen, setConfirmOpen] = useState(false);
+  const [confirmText, setConfirmText] = useState('');
+
+  const isCancelled = overview.status === 'cancelled';
+  const isTerminal = TERMINAL_STATUSES.has(overview.status);
+  // A draft has no on-chain escrow to refund; cancel only applies once funded.
+  const isPublished = !!overview.escrowEventId;
+  const running = cancelOp.isRunning;
+
+  return (
+    <div className='max-w-2xl space-y-6'>
+      <div className='rounded-2xl border border-red-500/30 bg-red-500/[0.04] p-5'>
+        <div className='flex items-start gap-3'>
+          <AlertTriangle className='mt-0.5 h-5 w-5 shrink-0 text-red-400' />
+          <div className='min-w-0 flex-1'>
+            <h3 className='text-sm font-semibold text-white'>
+              Cancel this bounty
+            </h3>
+            <p className='mt-1 text-sm text-zinc-400'>
+              Cancelling closes the bounty and refunds the locked escrow.
+              Contributors are refunded first, then any residual returns to you
+              as the owner. This runs once on-chain and cannot be undone.
+            </p>
+
+            {cancelOp.isCompleted || isCancelled ? (
+              <div className='mt-4 space-y-2 rounded-xl border border-zinc-800 bg-zinc-900/50 p-4'>
+                <div className='flex items-center gap-2 text-sm text-white'>
+                  <CheckCircle2 className='h-4 w-4 text-emerald-400' />
+                  This bounty is cancelled and the escrow was refunded.
+                </div>
+                {cancelOp.txHash && (
+                  <a
+                    href={getTransactionExplorerUrl(cancelOp.txHash)}
+                    target='_blank'
+                    rel='noreferrer'
+                    className='text-primary inline-flex items-center gap-1 text-xs hover:underline'
+                  >
+                    View refund transaction
+                    <ExternalLink className='h-3 w-3' />
+                  </a>
+                )}
+              </div>
+            ) : running ? (
+              <div className='mt-4 flex items-center gap-2 rounded-lg border border-zinc-800 bg-zinc-900/50 p-3 text-sm text-zinc-300'>
+                <Loader2 className='text-primary h-4 w-4 animate-spin' />
+                {PHASE_LABEL[cancelOp.phase] || 'Working…'}
+              </div>
+            ) : isTerminal ? (
+              <p className='mt-4 text-sm text-zinc-500'>
+                This bounty is {overview.status.replace(/_/g, ' ')} and can no
+                longer be cancelled.
+              </p>
+            ) : !isPublished ? (
+              <p className='mt-4 text-sm text-zinc-500'>
+                This bounty is still a draft with no funded escrow. Delete it
+                from your drafts instead.
+              </p>
+            ) : (
+              <BoundlessButton
+                variant='destructive'
+                className='mt-4'
+                onClick={() => {
+                  setConfirmText('');
+                  setConfirmOpen(true);
+                }}
+              >
+                Cancel bounty &amp; refund
+              </BoundlessButton>
+            )}
+          </div>
+        </div>
+      </div>
+
+      {/* Explicit-confirm gate before the irreversible on-chain refund. */}
+      <Dialog open={confirmOpen} onOpenChange={setConfirmOpen}>
+        <DialogContent className='border-zinc-800 bg-zinc-950 text-white'>
+          <DialogHeader>
+            <DialogTitle>Cancel this bounty?</DialogTitle>
+            <DialogDescription>
+              The escrow refunds in one on-chain transaction, contributors
+              first, then your owner residual. This cannot be undone or
+              reversed. Type{' '}
+              <span className='font-mono font-semibold text-red-400'>
+                {CONFIRM_PHRASE}
+              </span>{' '}
+              to confirm.
+            </DialogDescription>
+          </DialogHeader>
+          <div className='space-y-3'>
+            <div className='rounded-lg border border-zinc-800 bg-zinc-900/40 p-3 text-sm'>
+              <div className='flex items-center justify-between'>
+                <span className='text-zinc-400'>Reward pool</span>
+                <span className='font-semibold text-white'>
+                  {overview.rewardAmount.toLocaleString()}{' '}
+                  {overview.rewardCurrency}
+                </span>
+              </div>
+            </div>
+            <Input
+              autoFocus
+              value={confirmText}
+              onChange={e => setConfirmText(e.target.value)}
+              placeholder={`Type ${CONFIRM_PHRASE} to confirm`}
+              className='border-zinc-800 bg-zinc-900/50 text-white placeholder:text-zinc-600'
+            />
+          </div>
+          <DialogFooter>
+            <BoundlessButton
+              variant='outline'
+              onClick={() => setConfirmOpen(false)}
+            >
+              Keep bounty
+            </BoundlessButton>
+            <BoundlessButton
+              variant='destructive'
+              disabled={confirmText.trim() !== CONFIRM_PHRASE}
+              onClick={() => {
+                setConfirmOpen(false);
+                void cancelOp.cancel();
+              }}
+            >
+              Cancel bounty &amp; refund
+            </BoundlessButton>
+          </DialogFooter>
+        </DialogContent>
+      </Dialog>
+    </div>
+  );
+}
diff --git a/hooks/use-bounty-cancel.ts b/hooks/use-bounty-cancel.ts
new file mode 100644
index 00000000..156f5904
--- /dev/null
+++ b/hooks/use-bounty-cancel.ts
@@ -0,0 +1,110 @@
+import { useEffect, useRef } from 'react';
+import { useQueryClient } from '@tanstack/react-query';
+import { toast } from 'sonner';
+
+import { useWalletContext } from '@/components/providers/wallet-provider';
+import { signXdrWithKit } from '@/lib/wallet/wallet-kit';
+import {
+  bountyKeys,
+  useCancelBountyEscrow,
+  useEscrowOpRunner,
+  type CancelBountyEscrowRequest,
+  type FundingMode,
+} from '@/features/bounties';
+
+interface UseBountyCancelProps {
+  organizationId: string;
+  bountyId: string;
+  /** Signing path. Defaults to MANAGED (custodial). */
+  fundingMode?: FundingMode;
+  /** For EXTERNAL: the connected wallet that signs (owner of the escrow). */
+  externalOwnerAddress?: string | null;
+}
+
+/**
+ * Drives the single `cancel` op that aborts a published bounty and refunds the
+ * escrow (contributors first, then the owner residual). Mirrors useBountyPayout:
+ * MANAGED signs server-side (op comes back PENDING_CONFIRM), EXTERNAL returns an
+ * unsigned XDR the connected wallet signs. On settle the backend subscriber
+ * pushes the refunds and flips the bounty to CANCELLED; we invalidate the
+ * overview so the dashboard reflects the new state immediately.
+ */
+export const useBountyCancel = ({
+  organizationId,
+  bountyId,
+  fundingMode = 'MANAGED',
+  externalOwnerAddress,
+}: UseBountyCancelProps) => {
+  const { walletAddress } = useWalletContext();
+  const queryClient = useQueryClient();
+  const isExternal = fundingMode === 'EXTERNAL';
+  const ownerAddress = isExternal
+    ? (externalOwnerAddress ?? null)
+    : walletAddress;
+
+  const cancelMutation = useCancelBountyEscrow(organizationId, bountyId);
+  const runner = useEscrowOpRunner(
+    { kind: 'organizer', organizationId, bountyId },
+    isExternal ? { signXdr: signXdrWithKit } : undefined
+  );
+
+  // Toast each settle exactly once; the runner keeps its terminal flags set
+  // after a run, so this ref is what arms the next run's notifications.
+  const finalizedRef = useRef(false);
+
+  useEffect(() => {
+    if (finalizedRef.current) return;
+    if (runner.isCompleted) {
+      finalizedRef.current = true;
+      toast.success('Bounty cancelled and escrow refunded.', {
+        duration: 3000,
+      });
+      void queryClient.invalidateQueries({
+        queryKey: bountyKeys.overview(organizationId, bountyId),
+      });
+    } else if (runner.isFailed) {
+      finalizedRef.current = true;
+      toast.error(runner.error || 'Failed to cancel the bounty');
+    }
+  }, [
+    runner.isCompleted,
+    runner.isFailed,
+    runner.error,
+    queryClient,
+    organizationId,
+    bountyId,
+  ]);
+
+  const cancel = async (): Promise<void> => {
+    if (!organizationId || !bountyId) return;
+    if (!ownerAddress) {
+      toast.error(
+        isExternal
+          ? 'Connect a wallet to sign the cancellation.'
+          : 'Please connect your wallet first'
+      );
+      return;
+    }
+
+    const body: CancelBountyEscrowRequest = {
+      ownerAddress,
+      fundingMode,
+    };
+
+    finalizedRef.current = false;
+    toast.info('Submitting cancellation…');
+
+    await runner.run(() => cancelMutation.mutateAsync(body));
+  };
+
+  return {
+    cancel,
+    phase: runner.phase,
+    isRunning: runner.isRunning,
+    isCompleted: runner.isCompleted,
+    isFailed: runner.isFailed,
+    txHash: runner.txHash,
+    error: runner.error,
+    reset: runner.reset,
+  };
+};