diff --git a/api-v3/src/act-administration/field-briefing.service.ts b/api-v3/src/act-administration/field-briefing.service.ts
index 5b7f917..03df89c 100644
--- a/api-v3/src/act-administration/field-briefing.service.ts
+++ b/api-v3/src/act-administration/field-briefing.service.ts
@@ -36,6 +36,20 @@ export interface FieldBriefingAct {
   findings: FieldBriefingFinding[];
 }
 
+function toIsoDate(value: unknown): string {
+  const parsed = value instanceof Date
+    ? value
+    : value == null
+      ? new Date()
+      : new Date(String(value));
+
+  if (Number.isNaN(parsed.getTime())) {
+    throw new Error('La fecha planificada de la inspección no es válida');
+  }
+
+  return parsed.toISOString().slice(0, 10);
+}
+
 @Injectable()
 export class FieldBriefingService {
   constructor(private readonly dataSource: DataSource) {}
@@ -67,7 +81,9 @@ export class FieldBriefingService {
       });
     }
 
-    const plannedOn = String(visit.plannedStartAt ?? new Date().toISOString()).slice(0, 10);
+    // PostgreSQL/pg entrega los timestamptz como Date. String(date).slice(0, 10)
+    // produce textos como "Thu Sep 17", que PostgreSQL rechaza al castear a date.
+    const plannedOn = toIsoDate(visit.plannedStartAt);
 
     const rows = (await this.dataSource.query(`
       WITH prior_acts AS (
diff --git a/api-v3/test/unit/field-briefing-runtime.test.ts b/api-v3/test/unit/field-briefing-runtime.test.ts
new file mode 100644
index 0000000..2665d1d
--- /dev/null
+++ b/api-v3/test/unit/field-briefing-runtime.test.ts
@@ -0,0 +1,50 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+import type { DataSource } from 'typeorm';
+import { FieldBriefingService } from '../../src/act-administration/field-briefing.service';
+
+test('field briefing convierte el timestamptz de pg a YYYY-MM-DD antes del cast SQL', async () => {
+  const calls: Array<{ sql: string; params: unknown[] }> = [];
+  let queryNumber = 0;
+
+  const dataSource = {
+    query: async (sql: string, params: unknown[]) => {
+      calls.push({ sql, params });
+      queryNumber += 1;
+
+      if (queryNumber === 1) {
+        return [{
+          id: '11111111-1111-4111-8111-111111111111',
+          code: 'INSP-00002-17-09-26',
+          status: 'DRAFT',
+          plannedStartAt: new Date('2026-09-17T23:42:00.000Z'),
+          areaId: '22222222-2222-4222-8222-222222222222',
+          companyId: '33333333-3333-4333-8333-333333333333',
+          areaCode: 'PRES-AREA-TEST',
+          areaName: 'Barrancas',
+          companyCode: 'PRES-ORG-TEST',
+          companyName: 'Petróleos Sudamericanos Energy S.A.',
+        }];
+      }
+
+      return [];
+    },
+  } as unknown as DataSource;
+
+  const result = await new FieldBriefingService(dataSource).forVisit(
+    '11111111-1111-4111-8111-111111111111',
+  );
+
+  assert.equal(calls.length, 2);
+  assert.equal(calls[1]?.params[3], '2026-09-17');
+  assert.equal(result.plannedOn, '2026-09-17');
+  assert.deepEqual(result.summary, {
+    acts: 0,
+    findings: 0,
+    inventoryItems: 0,
+    responseOverdue: 0,
+    commitmentOverdue: 0,
+    verificationPending: 0,
+  });
+  assert.deepEqual(result.acts, []);
+});