diff --git a/app/api/invoices/[id]/mark-sent/__tests__/route.test.ts b/app/api/invoices/[id]/mark-sent/__tests__/route.test.ts
index 820d0954..3dfee258 100644
--- a/app/api/invoices/[id]/mark-sent/__tests__/route.test.ts
+++ b/app/api/invoices/[id]/mark-sent/__tests__/route.test.ts
@@ -40,6 +40,7 @@ vi.mock('@react-pdf/renderer', () => ({
 vi.mock('@/lib/invoices/pdf-template', () => ({
   InvoicePDF: vi.fn().mockReturnValue('mock-pdf-element'),
 }))
+import { InvoicePDF } from '@/lib/invoices/pdf-template'
 
 const mockCreateInvoiceJournalEntry = vi.fn()
 vi.mock('@/lib/bookkeeping/invoice-entries', () => ({
@@ -222,4 +223,26 @@ describe('POST /api/invoices/[id]/mark-sent — PDF archival', () => {
       expect.anything()
     )
   })
+
+  it('renders the archived PDF as if already sent (no UTKAST banner)', async () => {
+    enqueue({ data: invoice, error: null }) // fetch invoice (status: 'draft')
+    enqueue({ data: null, error: null }) // status update
+    enqueue({ data: company, error: null }) // settings
+    mockCreateInvoiceJournalEntry.mockResolvedValue({ id: 'je-99' })
+    enqueue({ data: null, error: null }) // update invoice with journal_entry_id
+
+    const request = createMockRequest('/api/invoices/inv-1/mark-sent', { method: 'POST' })
+    const response = await POST(request, createMockRouteParams({ id: 'inv-1' }))
+    const { status } = await parseJsonResponse(response)
+
+    expect(status).toBe(200)
+    // The in-memory invoice still reads 'draft' after the DB status flip
+    // (it's never re-fetched). We must override it before render or
+    // pdf-template.tsx prints the "UTKAST – inte en giltig faktura" banner
+    // on the archived underlag.
+    expect(vi.mocked(InvoicePDF)).toHaveBeenCalledTimes(1)
+    const renderArgs = vi.mocked(InvoicePDF).mock.calls[0][0]
+    expect(renderArgs.invoice.status).toBe('sent')
+    expect(renderArgs.invoice.invoice_number).toBe('F-2026010')
+  })
 })
diff --git a/app/api/invoices/[id]/mark-sent/route.ts b/app/api/invoices/[id]/mark-sent/route.ts
index 8ceb8045..ff95c8eb 100644
--- a/app/api/invoices/[id]/mark-sent/route.ts
+++ b/app/api/invoices/[id]/mark-sent/route.ts
@@ -131,9 +131,12 @@ export async function POST(
         originalInvoiceNumber = originalInvoice?.invoice_number ?? undefined
       }
 
+      // The DB status flip already happened above, but the in-memory `invoice`
+      // is stale and still reads 'draft' — override here so the archived
+      // underlag isn't stamped "UTKAST – inte en giltig faktura".
       const pdfBuffer = await renderToBuffer(
         InvoicePDF({
-          invoice: invoice as Invoice,
+          invoice: { ...(invoice as Invoice), status: 'sent' as const },
           customer: invoice.customer as Customer,
           items,
           company: settings as CompanySettings,
diff --git a/app/api/invoices/[id]/send/__tests__/route.test.ts b/app/api/invoices/[id]/send/__tests__/route.test.ts
index ada8c6f8..05c4067e 100644
--- a/app/api/invoices/[id]/send/__tests__/route.test.ts
+++ b/app/api/invoices/[id]/send/__tests__/route.test.ts
@@ -41,6 +41,7 @@ vi.mock('@react-pdf/renderer', () => ({
 vi.mock('@/lib/invoices/pdf-template', () => ({
   InvoicePDF: vi.fn().mockReturnValue('mock-pdf-element'),
 }))
+import { InvoicePDF } from '@/lib/invoices/pdf-template'
 
 const mockSendEmail = vi.fn()
 const mockIsConfigured = vi.fn()
@@ -364,4 +365,29 @@ describe('POST /api/invoices/[id]/send', () => {
       (body.error as unknown as { details?: { providerError?: string } }).details?.providerError,
     ).toContain('SMTP error')
   })
+
+  it('renders the final PDF as if already sent (no UTKAST banner)', async () => {
+    enqueue({ data: invoice, error: null })
+    enqueue({ data: company, error: null })
+
+    mockSendEmail.mockResolvedValue({ success: true, messageId: 'msg-banner' })
+    mockCreateInvoiceJournalEntry.mockResolvedValue({ id: 'je-1' })
+
+    enqueue({ data: null, error: null })
+    enqueue({ data: null, error: null })
+
+    const request = createMockRequest('/api/invoices/inv-1/send', { method: 'POST' })
+    const response = await POST(request, createMockRouteParams({ id: 'inv-1' }))
+    const { status } = await parseJsonResponse(response)
+
+    expect(status).toBe(200)
+    // Final render: invoice already has an invoice_number on the fixture, so
+    // preflight is skipped and InvoicePDF is called exactly once. The status
+    // passed in must be 'sent' — otherwise pdf-template.tsx renders the
+    // "UTKAST – inte en giltig faktura" banner on the customer's PDF.
+    expect(vi.mocked(InvoicePDF)).toHaveBeenCalledTimes(1)
+    const renderArgs = vi.mocked(InvoicePDF).mock.calls[0][0]
+    expect(renderArgs.invoice.status).toBe('sent')
+    expect(renderArgs.invoice.invoice_number).toBe('F-2024001')
+  })
 })
diff --git a/app/api/invoices/[id]/send/route.ts b/app/api/invoices/[id]/send/route.ts
index d1297964..fd46a782 100644
--- a/app/api/invoices/[id]/send/route.ts
+++ b/app/api/invoices/[id]/send/route.ts
@@ -117,10 +117,13 @@ export const POST = withRouteContext(
     }
 
     // Final render with the assigned number — this is the buffer attached to
-    // the email and later archived as underlag.
+    // the email and later archived as underlag. Override status to 'sent' on
+    // the in-memory copy: the DB flip happens after email delivery (line
+    // ~185), but if we render with the stale 'draft' status the customer
+    // receives a PDF stamped "UTKAST – inte en giltig faktura".
     const pdfBuffer = await renderToBuffer(
       InvoicePDF({
-        invoice: invoice as Invoice,
+        invoice: { ...(invoice as Invoice), status: 'sent' as const },
         customer,
         items,
         company: company as CompanySettings,
diff --git a/app/api/v1/companies/[companyId]/invoices/[id]/send/__tests__/route.test.ts b/app/api/v1/companies/[companyId]/invoices/[id]/send/__tests__/route.test.ts
index c2d7f4c5..85fe35c7 100644
--- a/app/api/v1/companies/[companyId]/invoices/[id]/send/__tests__/route.test.ts
+++ b/app/api/v1/companies/[companyId]/invoices/[id]/send/__tests__/route.test.ts
@@ -72,6 +72,7 @@ vi.mock('@/lib/email/invoice-templates', () => ({
 vi.mock('@/lib/invoices/pdf-template', () => ({
   InvoicePDF: vi.fn().mockReturnValue({}),
 }))
+import { InvoicePDF } from '@/lib/invoices/pdf-template'
 
 import { validateApiKey, createServiceClientNoCookies } from '@/lib/auth/api-keys'
 import { POST as sendInvoice } from '../route'
@@ -370,6 +371,36 @@ describe('POST /api/v1/companies/:companyId/invoices/:id/send', () => {
     )
   })
 
+  it('renders the final PDF as if already sent (no UTKAST banner)', async () => {
+    mockServiceClient.mockReturnValue(
+      makeFlexibleSupabase({
+        company_members: { data: { company_id: COMPANY_ID, role: 'owner' }, error: null },
+        invoices: [
+          { data: DRAFT_INVOICE, error: null }, // pre-flight fetch
+          { data: { invoice_number: '2026-0043' }, error: null }, // re-read after allocation
+        ],
+        company_settings: { data: COMPANY_SETTINGS, error: null },
+      }),
+    )
+
+    const res = await sendInvoice(
+      makeRequest(`https://x.test/api/v1/companies/${COMPANY_ID}/invoices/${INVOICE_ID}/send`),
+      detailParams(COMPANY_ID, INVOICE_ID),
+    )
+    expect(res.status).toBe(200)
+
+    // DRAFT_INVOICE has invoice_number: null, so isFreshAllocation is true and
+    // a preflight render runs first with the F-PREVIEW placeholder. The final
+    // render is the second call — its invoice must carry status: 'sent' and
+    // the freshly-assigned invoice_number, otherwise the customer's PDF is
+    // stamped "UTKAST – inte en giltig faktura".
+    const calls = vi.mocked(InvoicePDF).mock.calls
+    expect(calls.length).toBeGreaterThanOrEqual(2)
+    const finalRenderArgs = calls[calls.length - 1][0]
+    expect(finalRenderArgs.invoice.status).toBe('sent')
+    expect(finalRenderArgs.invoice.invoice_number).toBe('2026-0043')
+  })
+
   it('rejects keys without invoices:write scope', async () => {
     mockValidate.mockResolvedValue({
       userId: USER_ID,
diff --git a/app/api/v1/companies/[companyId]/invoices/[id]/send/route.ts b/app/api/v1/companies/[companyId]/invoices/[id]/send/route.ts
index 31461fb5..5f5cacea 100644
--- a/app/api/v1/companies/[companyId]/invoices/[id]/send/route.ts
+++ b/app/api/v1/companies/[companyId]/invoices/[id]/send/route.ts
@@ -340,9 +340,14 @@ export const POST = withApiV1<{ params: Promise<{ companyId: string; id: string
     }
     const finalInvoiceNumber =
       (numbered as { invoice_number?: string } | null)?.invoice_number ?? typed.invoice_number
+    // Also override `status` to 'sent' on the in-memory copy. The actual DB
+    // flip happens at step 9a (after email delivery), but if we render with
+    // the stale 'draft' status the customer receives a PDF stamped
+    // "UTKAST – inte en giltig faktura".
     const renderableInvoice: Invoice = {
       ...(typed as Invoice),
       invoice_number: finalInvoiceNumber,
+      status: 'sent',
     }
 
     let pdfBuffer: Buffer
diff --git a/lib/pending-operations/commit.ts b/lib/pending-operations/commit.ts
index 888769da..ec9c5a42 100644
--- a/lib/pending-operations/commit.ts
+++ b/lib/pending-operations/commit.ts
@@ -589,9 +589,12 @@ async function commitSendInvoice(
     if (orig) originalInvoiceNumber = orig.invoice_number
   }
 
+  // Override `status` to 'sent' on the in-memory copy. The DB flip happens
+  // after email delivery (line ~625); rendering with the stale 'draft' status
+  // would stamp the customer's PDF with "UTKAST – inte en giltig faktura".
   const pdfBuffer = await renderToBuffer(
     InvoicePDF({
-      invoice: invoice as Invoice,
+      invoice: { ...(invoice as Invoice), status: 'sent' as const },
       customer,
       items,
       company: company as CompanySettings,