diff --git a/backend/app/crud/entries.py b/backend/app/crud/entries.py
index eae2e1c..a9a56bd 100644
--- a/backend/app/crud/entries.py
+++ b/backend/app/crud/entries.py
@@ -1,5 +1,5 @@
 from nanoid import generate
-from sqlalchemy.orm import Session
+from sqlalchemy.orm import Session, joinedload
 
 from app.core.logging import get_logger
 from app.models.entries import Entry
@@ -8,6 +8,19 @@
 logger = get_logger(__name__)
 
 
+def get_all_entries(db: Session, skip: int = 0, limit: int = 100):
+    """Retrieve all entries from all newsletters, sorted by received date."""
+    logger.debug(f"Querying all entries with skip={skip}, limit={limit}")
+    return (
+        db.query(Entry)
+        .options(joinedload(Entry.newsletter))
+        .order_by(Entry.received_at.desc())
+        .offset(skip)
+        .limit(limit)
+        .all()
+    )
+
+
 def get_entries_by_newsletter(
     db: Session, newsletter_id: str, skip: int = 0, limit: int = 100
 ):
diff --git a/backend/app/routers/feeds.py b/backend/app/routers/feeds.py
index 9f9fbfd..0c4417d 100644
--- a/backend/app/routers/feeds.py
+++ b/backend/app/routers/feeds.py
@@ -4,12 +4,21 @@
 
 from app.core.database import get_db
 from app.core.logging import get_logger
-from app.services.feed_generator import generate_feed
+from app.services.feed_generator import generate_feed, generate_master_feed
 
 logger = get_logger(__name__)
 router = APIRouter()
 
 
+@router.get("/feeds/all")
+def get_master_feed(db: Session = Depends(get_db)):
+    """Generate a master Atom feed for all newsletters."""
+    logger.info("Generating master feed for all newsletters")
+    feed = generate_master_feed(db)
+    logger.info("Successfully generated master feed")
+    return Response(content=feed, media_type="application/atom+xml")
+
+
 @router.get("/feeds/{feed_identifier}")
 def get_newsletter_feed(feed_identifier: str, db: Session = Depends(get_db)):
     """Generate an Atom feed for a specific newsletter."""
diff --git a/backend/app/services/feed_generator.py b/backend/app/services/feed_generator.py
index 97e5f32..e6fb0b8 100644
--- a/backend/app/services/feed_generator.py
+++ b/backend/app/services/feed_generator.py
@@ -3,7 +3,7 @@
 from sqlalchemy.orm import Session
 
 from app.core.config import settings
-from app.crud.entries import get_entries_by_newsletter
+from app.crud.entries import get_all_entries, get_entries_by_newsletter
 from app.crud.newsletters import get_newsletter_by_identifier
 
 
@@ -41,3 +41,34 @@ def generate_feed(db: Session, feed_identifier: str):
             fe.published(entry.received_at)
 
     return fg.atom_str(pretty=True)
+
+
+def generate_master_feed(db: Session):
+    """Generate a master Atom feed for all newsletters."""
+    entries = get_all_entries(db)
+
+    feed_url = f"{settings.app_base_url}/feeds/all"
+    logo_url = f"{settings.app_base_url}/logo.png"
+    icon_url = f"{settings.app_base_url}/favicon.ico"
+
+    fg = FeedGenerator()
+    fg.id("urn:letterfeed:master")
+    fg.title("LetterFeed: All Newsletters")
+    fg.logo(logo_url)
+    fg.icon(icon_url)
+    fg.link(href=feed_url, rel="self")
+    fg.link(href=f"{settings.app_base_url}/", rel="alternate")
+    fg.description("A master feed of all your newsletters.")
+
+    for entry in entries:
+        fe = fg.add_entry()
+        fe.id(f"urn:letterfeed:entry:{entry.id}")
+        fe.title(f"[{entry.newsletter.name}] {entry.subject}")
+        fe.content(entry.body, type="html")
+        if entry.received_at.tzinfo is None:
+            timezone_aware_received_at = entry.received_at.replace(tzinfo=tz.tzutc())
+            fe.published(timezone_aware_received_at)
+        else:
+            fe.published(entry.received_at)
+
+    return fg.atom_str(pretty=True)
diff --git a/backend/app/tests/test_crud.py b/backend/app/tests/test_crud.py
index 3c1c9a1..7948ae0 100644
--- a/backend/app/tests/test_crud.py
+++ b/backend/app/tests/test_crud.py
@@ -1,9 +1,10 @@
+import time
 import uuid
 from unittest.mock import patch
 
 from sqlalchemy.orm import Session
 
-from app.crud.entries import create_entry, get_entries_by_newsletter
+from app.crud.entries import create_entry, get_all_entries, get_entries_by_newsletter
 from app.crud.newsletters import (
     create_newsletter,
     get_newsletter_by_identifier,
@@ -329,3 +330,59 @@ def test_create_multiple_entries_have_different_timestamps(db_session: Session):
     entry2 = create_entry(db_session, entry_data_2, newsletter.id)
 
     assert entry1.received_at != entry2.received_at
+
+
+def test_get_all_entries(db_session: Session):
+    """Test getting all entries from all newsletters."""
+    # Create two newsletters
+    newsletter1 = create_newsletter(
+        db_session,
+        NewsletterCreate(
+            name="Newsletter One", sender_emails=[f"one_{uuid.uuid4()}@test.com"]
+        ),
+    )
+    time.sleep(0.1)  # Ensure different timestamps
+    newsletter2 = create_newsletter(
+        db_session,
+        NewsletterCreate(
+            name="Newsletter Two", sender_emails=[f"two_{uuid.uuid4()}@test.com"]
+        ),
+    )
+
+    # Create entries for both
+    entry1 = create_entry(
+        db_session,
+        EntryCreate(
+            subject="Entry 1", body="Body 1", message_id=f"<{uuid.uuid4()}@test.com>"
+        ),
+        newsletter1.id,
+    )
+    time.sleep(0.1)
+    entry2 = create_entry(
+        db_session,
+        EntryCreate(
+            subject="Entry 2", body="Body 2", message_id=f"<{uuid.uuid4()}@test.com>"
+        ),
+        newsletter2.id,
+    )
+    time.sleep(0.1)
+    entry3 = create_entry(
+        db_session,
+        EntryCreate(
+            subject="Entry 3", body="Body 3", message_id=f"<{uuid.uuid4()}@test.com>"
+        ),
+        newsletter1.id,
+    )
+
+    # Get all entries
+    all_entries = get_all_entries(db_session, limit=10)
+
+    # Assertions
+    assert len(all_entries) == 3
+    # Check for descending order by received_at
+    assert all_entries[0].id == entry3.id
+    assert all_entries[1].id == entry2.id
+    assert all_entries[2].id == entry1.id
+    # Check that newsletter relationship is loaded
+    assert all_entries[0].newsletter.name == "Newsletter One"
+    assert all_entries[1].newsletter.name == "Newsletter Two"
diff --git a/backend/app/tests/test_services.py b/backend/app/tests/test_services.py
index 19e358d..823672c 100644
--- a/backend/app/tests/test_services.py
+++ b/backend/app/tests/test_services.py
@@ -7,7 +7,51 @@
 from app.crud.newsletters import create_newsletter
 from app.schemas.entries import EntryCreate
 from app.schemas.newsletters import NewsletterCreate
-from app.services.feed_generator import generate_feed
+from app.services.feed_generator import generate_feed, generate_master_feed
+
+
+def test_generate_master_feed(db_session: Session):
+    """Test the master feed generation for all newsletters."""
+    # Create newsletters and entries
+    nl1 = create_newsletter(
+        db_session,
+        NewsletterCreate(name="Newsletter A", sender_emails=["a@example.com"]),
+    )
+    create_entry(
+        db_session,
+        EntryCreate(
+            subject="Entry A1", body="<p>Body A1</p>", message_id=f"<{uuid.uuid4()}>"
+        ),
+        nl1.id,
+    )
+
+    nl2 = create_newsletter(
+        db_session,
+        NewsletterCreate(name="Newsletter B", sender_emails=["b@example.com"]),
+    )
+    create_entry(
+        db_session,
+        EntryCreate(
+            subject="Entry B1", body="<p>Body B1</p>", message_id=f"<{uuid.uuid4()}>"
+        ),
+        nl2.id,
+    )
+
+    # Generate the master feed
+    feed_xml = generate_master_feed(db_session)
+    assert feed_xml is not None
+
+    # Parse and verify
+    root = ET.fromstring(feed_xml)
+    ns = {"atom": "http://www.w3.org/2005/Atom"}
+    assert root.find("atom:title", ns).text == "LetterFeed: All Newsletters"
+    assert root.find("atom:id", ns).text == "urn:letterfeed:master"
+
+    entry_titles = {
+        entry.find("atom:title", ns).text for entry in root.findall("atom:entry", ns)
+    }
+    assert "[Newsletter A] Entry A1" in entry_titles
+    assert "[Newsletter B] Entry B1" in entry_titles
 
 
 def test_generate_feed(db_session: Session):
diff --git a/frontend/src/app/page.tsx b/frontend/src/app/page.tsx
index 39856ef..bf769c3 100644
--- a/frontend/src/app/page.tsx
+++ b/frontend/src/app/page.tsx
@@ -14,6 +14,7 @@ import { LoadingSpinner } from "@/components/letterfeed/LoadingSpinner"
 import { Header } from "@/components/letterfeed/Header"
 import { NewsletterList } from "@/components/letterfeed/NewsletterList"
 import { EmptyState } from "@/components/letterfeed/EmptyState"
+import { MasterFeedCard } from "@/components/letterfeed/MasterFeedCard"
 import { NewsletterDialog } from "@/components/letterfeed/NewsletterDialog"
 import { SettingsDialog } from "@/components/letterfeed/SettingsDialog"
 
@@ -68,6 +69,8 @@ function LetterFeedApp() {
           onOpenSettings={() => setIsSettingsOpen(true)}
         />
 
+        {newsletters.length > 0 && <MasterFeedCard />}
+
         {newsletters.length > 0 ? (
           <NewsletterList newsletters={newsletters} onEditNewsletter={openEditDialog} />
         ) : (
diff --git a/frontend/src/components/letterfeed/MasterFeedCard.tsx b/frontend/src/components/letterfeed/MasterFeedCard.tsx
new file mode 100644
index 0000000..5b598c2
--- /dev/null
+++ b/frontend/src/components/letterfeed/MasterFeedCard.tsx
@@ -0,0 +1,39 @@
+"use client"
+
+import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card"
+import { Rss, ExternalLink } from "lucide-react"
+import { getMasterFeedUrl } from "@/lib/api"
+
+export function MasterFeedCard() {
+  const feedUrl = getMasterFeedUrl()
+
+  return (
+    <Card className="mb-8">
+      <CardHeader>
+        <CardTitle className="flex items-center gap-2">
+          <Rss className="w-5 h-5 text-orange-500" />
+          Master Feed
+        </CardTitle>
+      </CardHeader>
+      <CardContent className="space-y-4">
+        <p className="text-sm text-muted-foreground">
+          This feed contains all entries from all your newsletters in one place.
+        </p>
+        <div>
+          <h4 className="text-sm font-medium text-gray-700 mb-2">RSS Feed URL</h4>
+          <div className="flex items-center gap-2">
+            <a
+              href={feedUrl}
+              target="_blank"
+              rel="noopener noreferrer"
+              className="inline-flex items-center gap-1 text-sm text-blue-600 hover:text-blue-800 hover:underline"
+            >
+              <ExternalLink className="w-3 h-3" />
+              {feedUrl}
+            </a>
+          </div>
+        </div>
+      </CardContent>
+    </Card>
+  )
+}
diff --git a/frontend/src/components/letterfeed/__tests__/MasterFeedCard.test.tsx b/frontend/src/components/letterfeed/__tests__/MasterFeedCard.test.tsx
new file mode 100644
index 0000000..a9aa334
--- /dev/null
+++ b/frontend/src/components/letterfeed/__tests__/MasterFeedCard.test.tsx
@@ -0,0 +1,45 @@
+import React from "react"
+import { render, screen } from "@testing-library/react"
+import "@testing-library/jest-dom"
+import { MasterFeedCard } from "../MasterFeedCard"
+
+// Mock the getMasterFeedUrl function
+jest.mock("@/lib/api", () => ({
+  ...jest.requireActual("@/lib/api"),
+  getMasterFeedUrl: jest.fn(() => "http://mock-api/feeds/all"),
+}))
+
+// Mock the toast
+jest.mock("sonner", () => ({
+  toast: {
+    success: jest.fn(),
+  },
+}))
+
+// Mock navigator.clipboard
+Object.assign(navigator, {
+  clipboard: {
+    writeText: jest.fn(),
+  },
+})
+
+describe("MasterFeedCard", () => {
+  beforeEach(() => {
+    jest.clearAllMocks()
+  })
+
+  it("renders the master feed card with the correct URL", () => {
+    render(<MasterFeedCard />)
+
+    expect(screen.getByText("Master Feed")).toBeInTheDocument()
+    expect(
+      screen.getByText(
+        "This feed contains all entries from all your newsletters in one place."
+      )
+    ).toBeInTheDocument()
+
+    const feedLink = screen.getByRole("link")
+    expect(feedLink).toHaveAttribute("href", "http://mock-api/feeds/all")
+    expect(feedLink).toHaveTextContent("http://mock-api/feeds/all")
+  })
+})
diff --git a/frontend/src/lib/api.ts b/frontend/src/lib/api.ts
index a91d975..f2198e1 100644
--- a/frontend/src/lib/api.ts
+++ b/frontend/src/lib/api.ts
@@ -208,3 +208,7 @@ export function getFeedUrl(newsletter: Newsletter): string {
     const feedIdentifier = newsletter.slug || newsletter.id;
     return `${API_BASE_URL}/feeds/${feedIdentifier}`;
 }
+
+export function getMasterFeedUrl(): string {
+    return `${API_BASE_URL}/feeds/all`;
+}