diff --git a/components/organization/bounties/new/NewBountyTab.tsx b/components/organization/bounties/new/NewBountyTab.tsx
index d8b5105e..d0429a63 100644
--- a/components/organization/bounties/new/NewBountyTab.tsx
+++ b/components/organization/bounties/new/NewBountyTab.tsx
@@ -7,6 +7,7 @@ import { toast } from 'sonner';
 import { Tabs, TabsContent } from '@/components/ui/tabs';
 import { useBountySteps } from '@/hooks/use-bounty-steps';
 import { useBountyDraft } from '@/hooks/use-bounty-draft';
+import { useBountyPublish } from '@/hooks/use-bounty-publish';
 import ScopeTab from './tabs/ScopeTab';
 import ModeTab from './tabs/ModeTab';
 import SubmissionModelTab from './tabs/SubmissionModelTab';
@@ -154,6 +155,16 @@ export default function NewBountyTab({
     ? { entryType: stepData.mode.entryType, claimType: stepData.mode.claimType }
     : undefined;
 
+  // Publish via the shared escrow runner. Defaults to MANAGED (the connected
+  // custodial wallet funds + the backend signs); the funding-source picker
+  // (external wallet / treasury) is a follow-up.
+  const { publish, isPublishing } = useBountyPublish({
+    organizationId: derivedOrgId || '',
+    stepData,
+    draftId,
+    fundingMode: 'MANAGED',
+  });
+
   if (isLoadingDraft) {
     return (
       <div className='bg-background-main-bg flex min-h-[60vh] flex-1 items-center justify-center text-white'>
@@ -231,12 +242,10 @@ export default function NewBountyTab({
               onEdit={navigateToStep}
               onSaveDraft={saveDraft}
               isSavingDraft={isSavingDraft}
-              // TODO(#601): wire the real publish + funding flow. For now the
-              // CTA enables once every section is valid, then reports that
-              // publishing lands in #601.
-              onPublish={() => {
-                toast.info('Publishing lands in #601 (escrow publish flow).');
+              onPublish={async () => {
+                await publish();
               }}
+              isLoading={isPublishing}
             />
           </TabsContent>
         </div>
diff --git a/hooks/use-bounty-publish.ts b/hooks/use-bounty-publish.ts
new file mode 100644
index 00000000..730d1c42
--- /dev/null
+++ b/hooks/use-bounty-publish.ts
@@ -0,0 +1,271 @@
+import { useEffect, useRef, useState } from 'react';
+import { toast } from 'sonner';
+
+import { useWalletContext } from '@/components/providers/wallet-provider';
+import { getTokenAddress } from '@/lib/config/tokens';
+import { signXdrWithKit } from '@/lib/wallet/wallet-kit';
+import {
+  clearPublishOpId,
+  persistPublishOpId,
+  readPublishOpId,
+} from '@/lib/utils/publish-op-storage';
+import {
+  getBountyEscrowOp,
+  useEscrowOpRunner,
+  usePublishBountyEscrow,
+  type FundingMode,
+  type PublishBountyEscrowRequest,
+} from '@/features/bounties';
+import {
+  getBountyPrizePool,
+  getBountyTotalFunding,
+  buildBountyWinnerDistribution,
+} from '@/lib/utils/bounty-escrow';
+import { getBountyDraft } from '@/features/bounties';
+import type { BountyFormData } from '@/components/organization/bounties/new/constants';
+
+interface UseBountyPublishProps {
+  organizationId: string;
+  stepData: BountyFormData;
+  draftId?: string | null;
+  /** Signing path. Defaults to MANAGED (custodial). */
+  fundingMode?: FundingMode;
+  /**
+   * For EXTERNAL funding, the connected wallet that funds + signs (Stellar
+   * Wallets Kit). Becomes the on-chain owner. Ignored for MANAGED.
+   */
+  externalOwnerAddress?: string | null;
+}
+
+export interface BountyPublishResponse {
+  id: string;
+  message: string;
+  transactionHash: string | null;
+}
+
+/** Lowercase bounty statuses that mean the bounty has left DRAFT already. */
+const PUBLISHED_STATUSES = new Set([
+  'open',
+  'in_progress',
+  'submitted',
+  'under_review',
+  'completed',
+  'cancelled',
+  'disputed',
+]);
+
+/**
+ * Publishes a bounty draft onto the boundless-events contract. The draft IS a
+ * Bounty row in `draft` status, so we hit the v2 escrow surface directly:
+ *
+ *   1. POST .../bounties/:draftId/escrow/publish (CREATE_EVENT). MANAGED has the
+ *      backend sign + submit (op comes back PENDING_CONFIRM); EXTERNAL returns
+ *      an unsigned XDR the connected wallet signs.
+ *   2. Poll the op to COMPLETED; the backend subscriber flips the bounty
+ *      draft_awaiting_funding -> open on settle.
+ *
+ * Mirrors useHackathonPublish. Treasury funding (sourceWalletId) is omitted
+ * until the backend treasury-parity issue (boundless-nestjs #314) lands.
+ */
+export const useBountyPublish = ({
+  organizationId,
+  stepData,
+  draftId,
+  fundingMode = 'MANAGED',
+  externalOwnerAddress,
+}: UseBountyPublishProps) => {
+  const { walletAddress, balances } = useWalletContext();
+  const bountyId = draftId || '';
+  const isExternal = fundingMode === 'EXTERNAL';
+
+  // The on-chain owner/source. EXTERNAL funds from the connected wallet;
+  // MANAGED from the caller's platform-held custodial wallet.
+  const ownerAddress = isExternal
+    ? (externalOwnerAddress ?? null)
+    : walletAddress;
+
+  const publishMutation = usePublishBountyEscrow(organizationId, bountyId);
+  const runner = useEscrowOpRunner(
+    { kind: 'organizer', organizationId, bountyId },
+    isExternal ? { signXdr: signXdrWithKit } : undefined
+  );
+
+  const [hasStarted, setHasStarted] = useState(false);
+  const [publishResponse, setPublishResponse] =
+    useState<BountyPublishResponse | null>(null);
+  const finalizedRef = useRef(false);
+
+  useEffect(() => {
+    if (!hasStarted || finalizedRef.current) return;
+
+    if (runner.isCompleted) {
+      finalizedRef.current = true;
+      setPublishResponse({
+        id: bountyId,
+        message: 'Bounty published successfully',
+        transactionHash: runner.txHash,
+      });
+      clearPublishOpId(bountyId);
+      toast.success('Bounty published!', { duration: 3000 });
+      setHasStarted(false);
+    } else if (runner.isFailed) {
+      finalizedRef.current = true;
+      // The backend returns the bounty to DRAFT on a failed CREATE_EVENT, so
+      // drop the stale op id; the next attempt starts a fresh publish.
+      clearPublishOpId(bountyId);
+      toast.error(runner.error || 'Failed to publish bounty');
+      setHasStarted(false);
+    }
+  }, [
+    hasStarted,
+    runner.isCompleted,
+    runner.isFailed,
+    runner.error,
+    runner.txHash,
+    bountyId,
+  ]);
+
+  const publish = async (): Promise<BountyPublishResponse | null> => {
+    if (!organizationId) {
+      toast.error('Organization ID is required');
+      return null;
+    }
+    if (!bountyId) {
+      toast.error('Draft ID is required');
+      return null;
+    }
+    if (!ownerAddress) {
+      toast.error(
+        isExternal
+          ? 'Connect a wallet to fund externally.'
+          : 'Please connect your wallet first'
+      );
+      return null;
+    }
+
+    // Pre-flight: a prior publish may have moved the bounty out of draft. The
+    // backend rejects re-publishing a draft_awaiting_funding row, so resume the
+    // in-flight op (or report the terminal state) instead.
+    let currentStatus: string | undefined;
+    try {
+      const draft = await getBountyDraft(organizationId, bountyId);
+      currentStatus = draft.status;
+    } catch {
+      // Non-fatal: fall through to the normal publish path.
+    }
+
+    if (currentStatus && PUBLISHED_STATUSES.has(currentStatus)) {
+      clearPublishOpId(bountyId);
+      toast.success('This bounty is already published.');
+      return null;
+    }
+
+    if (currentStatus === 'draft_awaiting_funding') {
+      const storedOpRowId = readPublishOpId(bountyId);
+      if (!storedOpRowId) {
+        toast.info(
+          'This bounty is already being funded on-chain. It will finish ' +
+            'publishing shortly, or return to draft if the transaction fails — ' +
+            'refresh in a moment to check.'
+        );
+        return null;
+      }
+      finalizedRef.current = false;
+      setHasStarted(true);
+      toast.info('Resuming bounty funding…');
+      await runner.run(() =>
+        getBountyEscrowOp(organizationId, bountyId, storedOpRowId)
+      );
+      return null;
+    }
+
+    // ---- Normal draft publish path ----
+    const reward = stepData.reward;
+    const submission = stepData.submission;
+    if (!reward || (reward.prizeTiers?.length ?? 0) === 0) {
+      toast.error('Add at least one prize tier before publishing');
+      return null;
+    }
+    if (!submission?.submissionDeadline) {
+      toast.error('A submission deadline is required before publishing');
+      return null;
+    }
+
+    const budget = getBountyPrizePool(reward);
+    if (!(budget > 0)) {
+      toast.error('Total prize amount must be greater than zero');
+      return null;
+    }
+
+    // create_event debits budget + platform fee from the owner's USDC. Catch an
+    // insufficient/missing balance here (MANAGED only — EXTERNAL funds from a
+    // wallet whose balance we don't track) with a clear message.
+    const required = getBountyTotalFunding(reward);
+    const usdcEntry = balances.find(b => b.asset_code === 'USDC');
+    const usdcBalance = parseFloat(usdcEntry?.balance ?? '0');
+    const fmt = (n: number) =>
+      n.toLocaleString('en-US', { maximumFractionDigits: 2 });
+    if (!isExternal && balances.length > 0 && usdcBalance < required) {
+      toast.error(
+        usdcEntry
+          ? `Insufficient USDC. Publishing locks ${fmt(required)} USDC ` +
+              `(${fmt(budget)} prizes + ${fmt(required - budget)} fee), but ` +
+              `your wallet has ${fmt(usdcBalance)} USDC.`
+          : `Your wallet has no USDC. Publishing locks ${fmt(required)} USDC. ` +
+              `Add USDC (and a USDC trustline) before publishing.`
+      );
+      return null;
+    }
+
+    let tokenAddress: string;
+    try {
+      tokenAddress = getTokenAddress('USDC');
+    } catch (err) {
+      toast.error(
+        err instanceof Error ? err.message : 'Prize token is not configured'
+      );
+      return null;
+    }
+
+    const deadlineMs = new Date(submission.submissionDeadline).getTime();
+    if (Number.isNaN(deadlineMs)) {
+      toast.error('Submission deadline is invalid');
+      return null;
+    }
+    const submissionDeadline = Math.floor(deadlineMs / 1000);
+
+    const body: PublishBountyEscrowRequest = {
+      ownerAddress,
+      tokenAddress,
+      budget: String(budget),
+      submissionDeadline,
+      applicationCreditCost: submission.applicationCreditCost ?? 1,
+      winnerDistribution: buildBountyWinnerDistribution(reward),
+      fundingMode,
+    };
+
+    finalizedRef.current = false;
+    setHasStarted(true);
+    setPublishResponse(null);
+    toast.info('Publishing bounty...');
+
+    const op = await runner.run(async () => {
+      const created = await publishMutation.mutateAsync(body);
+      persistPublishOpId(bountyId, created.id);
+      return created;
+    });
+
+    if (!op) setHasStarted(false);
+    return null;
+  };
+
+  return {
+    isPublishing: hasStarted && (publishMutation.isPending || runner.isRunning),
+    publish,
+    publishResponse,
+    escrowStatus: runner.status,
+    escrowPhase: runner.phase,
+    escrowError: runner.error,
+    escrowTxHash: runner.txHash,
+  };
+};