diff --git a/src/lib/__tests__/financial-report-service.test.ts b/src/lib/__tests__/financial-report-service.test.ts
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+/**
+ * Financial Report Service Integration Tests
+ *
+ * Tests the financial report engine:
+ * - Trial Balance: totalDebits === totalCredits (self-verifying)
+ * - Income Statement: revenue - expenses = net income
+ * - Balance Sheet: assets = liabilities + equity (balanced)
+ * - Drill-down: account entries with running balance
+ *
+ * Setup creates known transactions:
+ *   1. Invoice: DR 1100 AR, CR 4010 Revenue for 1000.00
+ *   2. Payment: DR 1010 Cash, CR 1100 AR for 1000.00
+ *   3. Expense: DR 5040 Internet Bandwidth, CR 1010 Cash for 300.00
+ *   4. Expense: DR 5090 Other Expense, CR 1010 Cash for 100.00
+ *
+ * Known balances:
+ *   - Revenue (4010): 1000
+ *   - Expenses: 400 total (5040=300, 5090=100)
+ *   - Net Income: 600
+ *   - Cash (1010): 600 (1000 received - 300 - 100)
+ *   - AR (1100): 0 (1000 - 1000)
+ *
+ * CLEANUP ORDER:
+ * journalEntryLines -> null reversesEntryId -> journalEntries ->
+ * accountingPeriods -> accounts -> ticketCategories -> expenseCategories ->
+ * users -> tenant
+ */
+
+import { prisma } from "@/lib/prisma";
+import { withTenantContext } from "@/lib/prisma-tenant";
+import { seedChartOfAccounts } from "@/lib/accounting/seed-coa";
+import { JournalEntryService } from "@/lib/accounting/journal-entry-service";
+import { FinancialReportService } from "@/lib/services/financial-report-service";
+import { Prisma, Role, TenantStatus, JournalEntrySource } from "@prisma/client";
+
+// ---------------------------------------------------------------------------
+// Shared test state
+// ---------------------------------------------------------------------------
+
+const TS = Date.now();
+
+let tenantId: string;
+let userId: string;
+
+// Account IDs
+let cashAccountId: string;    // 1010
+let arAccountId: string;      // 1100
+let revenueAccountId: string; // 4010
+let bandwidthAccountId: string; // 5040
+let otherExpenseAccountId: string; // 5090
+
+// Test dates
+const testDate = new Date("2026-02-15T00:00:00Z");
+const testStartDate = new Date("2026-02-01T00:00:00Z");
+const testEndDate = new Date("2026-02-28T23:59:59Z");
+const futureDate = new Date("2026-04-15T00:00:00Z");
+
+// ---------------------------------------------------------------------------
+// Helpers
+// ---------------------------------------------------------------------------
+
+function tp() {
+  return withTenantContext(tenantId);
+}
+
+// ---------------------------------------------------------------------------
+// Setup / Teardown
+// ---------------------------------------------------------------------------
+
+beforeAll(async () => {
+  // Create tenant
+  const tenant = await prisma.tenant.create({
+    data: {
+      name: `FinReport Test Tenant ${TS}`,
+      slug: `finreport-test-${TS}`,
+      ownerEmail: `finreport-${TS}@test.example`,
+      status: TenantStatus.ACTIVE,
+    },
+  });
+  tenantId = tenant.id;
+
+  // Seed COA
+  await prisma.$transaction(async (tx) => {
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    await seedChartOfAccounts(tx as any, tenantId);
+  });
+
+  // Create admin user
+  const user = await prisma.user.create({
+    data: {
+      email: `finreport-admin-${TS}@test.example`,
+      passwordHash: "hashed",
+      firstName: "FinReport",
+      lastName: "Admin",
+      tenantId,
+      roles: [Role.ADMIN],
+      isActive: true,
+    },
+  });
+  userId = user.id;
+
+  // Look up account IDs
+  const accounts = await prisma.account.findMany({
+    where: { tenantId, code: { in: ["1010", "1100", "4010", "5040", "5090"] } },
+    select: { id: true, code: true },
+  });
+  const accountMap = new Map(accounts.map((a) => [a.code, a.id]));
+  cashAccountId = accountMap.get("1010")!;
+  arAccountId = accountMap.get("1100")!;
+  revenueAccountId = accountMap.get("4010")!;
+  bandwidthAccountId = accountMap.get("5040")!;
+  otherExpenseAccountId = accountMap.get("5090")!;
+
+  expect(cashAccountId).toBeDefined();
+  expect(arAccountId).toBeDefined();
+  expect(revenueAccountId).toBeDefined();
+  expect(bandwidthAccountId).toBeDefined();
+  expect(otherExpenseAccountId).toBeDefined();
+
+  // Create known transactions via JournalEntryService
+  const tenantPrisma = tp();
+
+  // 1. Invoice: DR 1100 AR 1000, CR 4010 Revenue 1000
+  await JournalEntryService.createEntry({
+    tenantPrisma,
+    tenantId,
+    date: testDate,
+    description: "Invoice #1 - Subscription",
+    lines: [
+      { accountId: arAccountId, debit: 1000, credit: 0 },
+      { accountId: revenueAccountId, debit: 0, credit: 1000 },
+    ],
+    source: JournalEntrySource.SYSTEM,
+    referenceType: "Invoice",
+    createdById: userId,
+  });
+
+  // 2. Payment: DR 1010 Cash 1000, CR 1100 AR 1000
+  await JournalEntryService.createEntry({
+    tenantPrisma,
+    tenantId,
+    date: testDate,
+    description: "Payment received for Invoice #1",
+    lines: [
+      { accountId: cashAccountId, debit: 1000, credit: 0 },
+      { accountId: arAccountId, debit: 0, credit: 1000 },
+    ],
+    source: JournalEntrySource.SYSTEM,
+    referenceType: "Payment",
+    createdById: userId,
+  });
+
+  // 3. Expense: DR 5040 Internet Bandwidth 300, CR 1010 Cash 300
+  await JournalEntryService.createEntry({
+    tenantPrisma,
+    tenantId,
+    date: testDate,
+    description: "Internet bandwidth payment",
+    lines: [
+      { accountId: bandwidthAccountId, debit: 300, credit: 0 },
+      { accountId: cashAccountId, debit: 0, credit: 300 },
+    ],
+    source: JournalEntrySource.SYSTEM,
+    referenceType: "Expense",
+    createdById: userId,
+  });
+
+  // 4. Expense: DR 5090 Other Expense 100, CR 1010 Cash 100
+  await JournalEntryService.createEntry({
+    tenantPrisma,
+    tenantId,
+    date: testDate,
+    description: "Miscellaneous office expense",
+    lines: [
+      { accountId: otherExpenseAccountId, debit: 100, credit: 0 },
+      { accountId: cashAccountId, debit: 0, credit: 100 },
+    ],
+    source: JournalEntrySource.SYSTEM,
+    referenceType: "Expense",
+    createdById: userId,
+  });
+
+  // 5. Future entry (for date filtering tests): DR 5090 200, CR 1010 200
+  await JournalEntryService.createEntry({
+    tenantPrisma,
+    tenantId,
+    date: futureDate,
+    description: "Future expense for date filter test",
+    lines: [
+      { accountId: otherExpenseAccountId, debit: 200, credit: 0 },
+      { accountId: cashAccountId, debit: 0, credit: 200 },
+    ],
+    source: JournalEntrySource.SYSTEM,
+    referenceType: "Expense",
+    createdById: userId,
+  });
+}, 30000);
+
+afterAll(async () => {
+  // Cleanup order:
+  // journalEntryLines -> null reversesEntryId -> journalEntries ->
+  // accountingPeriods -> accounts -> ticketCategories -> expenseCategories ->
+  // users -> tenant
+  await prisma.journalEntryLine.deleteMany({ where: { tenantId } });
+  await prisma.journalEntry.updateMany({
+    where: { tenantId, reversesEntryId: { not: null } },
+    data: { reversesEntryId: null },
+  });
+  await prisma.journalEntry.deleteMany({ where: { tenantId } });
+  await prisma.accountingPeriod.deleteMany({ where: { tenantId } });
+  await prisma.account.deleteMany({ where: { tenantId } });
+  await prisma.ticketCategory.deleteMany({ where: { tenantId } });
+  await prisma.expenseCategory.deleteMany({ where: { tenantId } });
+  await prisma.user.deleteMany({ where: { tenantId } });
+  await prisma.tenant.deleteMany({ where: { id: tenantId } });
+});
+
+// ---------------------------------------------------------------------------
+// Trial Balance Tests
+// ---------------------------------------------------------------------------
+
+describe("Trial Balance", () => {
+  it("totalDebits equals totalCredits (isBalanced = true)", async () => {
+    const report = await FinancialReportService.getTrialBalance(tp());
+
+    expect(report.isBalanced).toBe(true);
+    expect(report.totalDebits.equals(report.totalCredits)).toBe(true);
+  });
+
+  it("each account shows correct debit or credit balance", async () => {
+    const report = await FinancialReportService.getTrialBalance(tp());
+
+    const lineMap = new Map(report.lines.map((l) => [l.accountCode, l]));
+
+    // Cash 1010: debit balance = 1000 - 300 - 100 - 200 = 400 (includes future entry)
+    const cash = lineMap.get("1010")!;
+    expect(cash.debitBalance.toNumber()).toBe(400);
+    expect(cash.creditBalance.toNumber()).toBe(0);
+
+    // AR 1100: debit balance = 1000 - 1000 = 0
+    const ar = lineMap.get("1100")!;
+    expect(ar.debitBalance.toNumber()).toBe(0);
+    expect(ar.creditBalance.toNumber()).toBe(0);
+
+    // Revenue 4010: credit balance = 1000
+    const revenue = lineMap.get("4010")!;
+    expect(revenue.creditBalance.toNumber()).toBe(1000);
+    expect(revenue.debitBalance.toNumber()).toBe(0);
+
+    // Bandwidth 5040: debit balance = 300
+    const bandwidth = lineMap.get("5040")!;
+    expect(bandwidth.debitBalance.toNumber()).toBe(300);
+
+    // Other Expense 5090: debit balance = 100 + 200 = 300 (includes future entry)
+    const other = lineMap.get("5090")!;
+    expect(other.debitBalance.toNumber()).toBe(300);
+  });
+
+  it("asOfDate filter excludes entries after the date", async () => {
+    // As of end of February: excludes future April entry
+    const report = await FinancialReportService.getTrialBalance(tp(), {
+      asOfDate: testEndDate,
+    });
+
+    expect(report.isBalanced).toBe(true);
+
+    const lineMap = new Map(report.lines.map((l) => [l.accountCode, l]));
+
+    // Cash 1010: 1000 - 300 - 100 = 600 (future 200 excluded)
+    const cash = lineMap.get("1010")!;
+    expect(cash.debitBalance.toNumber()).toBe(600);
+
+    // Other Expense 5090: 100 only (future 200 excluded)
+    const other = lineMap.get("5090")!;
+    expect(other.debitBalance.toNumber()).toBe(100);
+  });
+});
+
+// ---------------------------------------------------------------------------
+// Income Statement Tests
+// ---------------------------------------------------------------------------
+
+describe("Income Statement", () => {
+  it("revenue section shows Subscription Revenue = 1000", async () => {
+    const report = await FinancialReportService.getIncomeStatement(tp(), {
+      startDate: testStartDate,
+      endDate: testEndDate,
+    });
+
+    expect(report.revenue.accounts.length).toBeGreaterThanOrEqual(1);
+    const subRevenue = report.revenue.accounts.find((a) => a.code === "4010");
+    expect(subRevenue).toBeDefined();
+    expect(subRevenue!.balance.toNumber()).toBe(1000);
+  });
+
+  it("expense section shows correct expense accounts", async () => {
+    const report = await FinancialReportService.getIncomeStatement(tp(), {
+      startDate: testStartDate,
+      endDate: testEndDate,
+    });
+
+    const bandwidth = report.expenses.accounts.find((a) => a.code === "5040");
+    expect(bandwidth).toBeDefined();
+    expect(bandwidth!.balance.toNumber()).toBe(300);
+
+    const other = report.expenses.accounts.find((a) => a.code === "5090");
+    expect(other).toBeDefined();
+    expect(other!.balance.toNumber()).toBe(100);
+  });
+
+  it("netIncome = revenue total - expense total = 600", async () => {
+    const report = await FinancialReportService.getIncomeStatement(tp(), {
+      startDate: testStartDate,
+      endDate: testEndDate,
+    });
+
+    expect(report.revenue.total.toNumber()).toBe(1000);
+    expect(report.expenses.total.toNumber()).toBe(400);
+    expect(report.netIncome.toNumber()).toBe(600);
+  });
+
+  it("excludes header accounts (4000, 5000 not in report lines)", async () => {
+    const report = await FinancialReportService.getIncomeStatement(tp(), {
+      startDate: testStartDate,
+      endDate: testEndDate,
+    });
+
+    const allCodes = [
+      ...report.revenue.accounts.map((a) => a.code),
+      ...report.expenses.accounts.map((a) => a.code),
+    ];
+    expect(allCodes).not.toContain("4000");
+    expect(allCodes).not.toContain("5000");
+  });
+
+  it("date range filtering excludes entries outside range", async () => {
+    // Use a narrow range that excludes all entries
+    const report = await FinancialReportService.getIncomeStatement(tp(), {
+      startDate: new Date("2026-01-01T00:00:00Z"),
+      endDate: new Date("2026-01-31T23:59:59Z"),
+    });
+
+    expect(report.revenue.total.toNumber()).toBe(0);
+    expect(report.expenses.total.toNumber()).toBe(0);
+    expect(report.netIncome.toNumber()).toBe(0);
+    expect(report.revenue.accounts.length).toBe(0);
+    expect(report.expenses.accounts.length).toBe(0);
+  });
+});
+
+// ---------------------------------------------------------------------------
+// Balance Sheet Tests
+// ---------------------------------------------------------------------------
+
+describe("Balance Sheet", () => {
+  it("totalAssets = totalLiabilities + totalEquity (isBalanced = true)", async () => {
+    const report = await FinancialReportService.getBalanceSheet(tp(), {
+      asOfDate: testEndDate,
+    });
+
+    expect(report.isBalanced).toBe(true);
+    expect(
+      report.totalAssets.equals(report.totalLiabilitiesAndEquity)
+    ).toBe(true);
+  });
+
+  it("assets section shows Cash on Hand = 600", async () => {
+    const report = await FinancialReportService.getBalanceSheet(tp(), {
+      asOfDate: testEndDate,
+    });
+
+    const cash = report.assets.accounts.find((a) => a.code === "1010");
+    expect(cash).toBeDefined();
+    expect(cash!.balance.toNumber()).toBe(600);
+
+    // AR should be 0 and thus omitted (non-zero balances only)
+    const ar = report.assets.accounts.find((a) => a.code === "1100");
+    expect(ar).toBeUndefined();
+  });
+
+  it("equity section includes computed Net Income line", async () => {
+    const report = await FinancialReportService.getBalanceSheet(tp(), {
+      asOfDate: testEndDate,
+    });
+
+    // Net income = 1000 revenue - 400 expenses = 600
+    expect(report.equity.netIncome.toNumber()).toBe(600);
+
+    // Total equity = equity account balances + net income
+    expect(report.equity.total.toNumber()).toBe(600);
+  });
+
+  it("asOfDate filtering works", async () => {
+    // Including future entries should change balances
+    const reportFuture = await FinancialReportService.getBalanceSheet(tp(), {
+      asOfDate: new Date("2026-12-31T23:59:59Z"),
+    });
+
+    const cash = reportFuture.assets.accounts.find((a) => a.code === "1010");
+    expect(cash).toBeDefined();
+    // Cash: 1000 - 300 - 100 - 200 = 400
+    expect(cash!.balance.toNumber()).toBe(400);
+
+    // Net income with future: 1000 - 400 - 200 = 400
+    expect(reportFuture.equity.netIncome.toNumber()).toBe(400);
+
+    // Still balanced
+    expect(reportFuture.isBalanced).toBe(true);
+  });
+});
+
+// ---------------------------------------------------------------------------
+// Drill-down (Account Entries) Tests
+// ---------------------------------------------------------------------------
+
+describe("Account Entries (Drill-down)", () => {
+  it("Cash on Hand (1010) shows all entries with running balance", async () => {
+    const report = await FinancialReportService.getAccountEntries(tp(), {
+      accountId: cashAccountId,
+      startDate: testStartDate,
+      endDate: testEndDate,
+    });
+
+    expect(report.accountCode).toBe("1010");
+    expect(report.accountName).toBe("Cash on Hand");
+    expect(report.entries.length).toBe(3); // payment credit, 2 expense debits
+
+    // Running balance should end at 600
+    const lastEntry = report.entries[report.entries.length - 1];
+    expect(lastEntry.runningBalance.toNumber()).toBe(600);
+
+    // First entry is the payment (debit 1000 to cash)
+    expect(report.entries[0].debit.toNumber()).toBe(1000);
+    expect(report.entries[0].runningBalance.toNumber()).toBe(1000);
+  });
+
+  it("entries include entryNumber, description, referenceType", async () => {
+    const report = await FinancialReportService.getAccountEntries(tp(), {
+      accountId: cashAccountId,
+      startDate: testStartDate,
+      endDate: testEndDate,
+    });
+
+    for (const entry of report.entries) {
+      expect(entry.entryNumber).toBeDefined();
+      expect(entry.entryNumber).toMatch(/^JE-\d{4}-\d{4}$/);
+      expect(entry.description).toBeDefined();
+      expect(typeof entry.description).toBe("string");
+      // referenceType may be null but should be present
+      expect("referenceType" in entry).toBe(true);
+    }
+
+    // Check specific referenceTypes
+    const refTypes = report.entries.map((e) => e.referenceType);
+    expect(refTypes).toContain("Payment");
+    expect(refTypes).toContain("Expense");
+  });
+});
+
+// ---------------------------------------------------------------------------
+// Edge Cases
+// ---------------------------------------------------------------------------
+
+describe("Edge Cases", () => {
+  it("empty tenant — Trial Balance returns lines with zero balances, isBalanced = true", async () => {
+    // Create a fresh empty tenant
+    const emptyTenant = await prisma.tenant.create({
+      data: {
+        name: `Empty FinReport Tenant ${TS}`,
+        slug: `empty-finreport-${TS}`,
+        ownerEmail: `empty-finreport-${TS}@test.example`,
+        status: TenantStatus.ACTIVE,
+      },
+    });
+    const emptyTenantId = emptyTenant.id;
+
+    try {
+      // Seed COA but no journal entries
+      await prisma.$transaction(async (tx) => {
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        await seedChartOfAccounts(tx as any, emptyTenantId);
+      });
+
+      const emptyTp = withTenantContext(emptyTenantId);
+      const report = await FinancialReportService.getTrialBalance(emptyTp);
+
+      expect(report.isBalanced).toBe(true);
+      expect(report.totalDebits.toNumber()).toBe(0);
+      expect(report.totalCredits.toNumber()).toBe(0);
+      // Should have lines (all zero balance)
+      expect(report.lines.length).toBeGreaterThan(0);
+    } finally {
+      // Cleanup empty tenant
+      await prisma.account.deleteMany({ where: { tenantId: emptyTenantId } });
+      await prisma.tenant.deleteMany({ where: { id: emptyTenantId } });
+    }
+  });
+
+  it("all reports return only leaf accounts (no category headers)", async () => {
+    const tb = await FinancialReportService.getTrialBalance(tp());
+    const is = await FinancialReportService.getIncomeStatement(tp(), {
+      startDate: testStartDate,
+      endDate: testEndDate,
+    });
+    const bs = await FinancialReportService.getBalanceSheet(tp(), {
+      asOfDate: testEndDate,
+    });
+
+    // Income Statement: no header codes
+    const isCodes = [
+      ...is.revenue.accounts.map((a) => a.code),
+      ...is.expenses.accounts.map((a) => a.code),
+    ];
+    for (const code of isCodes) {
+      expect(code.endsWith("000")).toBe(false);
+    }
+
+    // Balance Sheet: no header codes
+    const bsCodes = [
+      ...bs.assets.accounts.map((a) => a.code),
+      ...bs.liabilities.accounts.map((a) => a.code),
+      ...bs.equity.accounts.map((a) => a.code),
+    ];
+    for (const code of bsCodes) {
+      expect(code.endsWith("000")).toBe(false);
+    }
+
+    // Trial Balance includes all accounts (including headers) — but that's by design
+    // since it uses JournalEntryService.getTrialBalance which returns all accounts
+    expect(tb.lines.length).toBeGreaterThan(0);
+  });
+});