diff --git a/CLAUDE.md b/CLAUDE.md
index 9dc0268..1a9735e 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -33,7 +33,7 @@ The binary is a single Go process that scrapes GraceNote/TMS for 14 days of TV l
 
 1. `/setup` uses `web.ProviderClient` to discover Gracenote lineups by country and postal code. `appconfig.Store` persists the selected non-secret source in `config.json`; complete legacy `GN_*` settings can bootstrap it.
 2. `web.Client.GetDataByTime` fetches 6-hour grid slices from the GraceNote API (`tvlistings.gracenote.com/api/grid`) — 56 slots for 14 days. A 5-second sleep separates requests. Raw JSON types live in `web/web.go`.
-3. `guide.ConvertChannel` / `guide.ConvertEvent` translate the raw JSON into `guide.TVGuide` (internal canonical types). The `guide.tmpl` template renders these to XMLTV. `index.html`, `setup.html`, and `guide.tmpl` are embedded at build time via `//go:embed`.
+3. `guide.ConvertChannel` / `guide.ConvertEvent` translate the raw JSON into `guide.TVGuide` (internal canonical types). `TVGuide.Channels` is deduplicated by station for XMLTV; `TVGuide.Lineup` retains every provider position (number plus station) and is served by `/api/lineup.json`. `TVGuide.Source` records the lineup the guide came from. The `guide.tmpl` template renders these to XMLTV. `index.html`, `setup.html`, and `guide.tmpl` are embedded at build time via `//go:embed`.
 4. `tmdb.Client.Lookup` enriches programs (poster images, ratings, overview, year) via TMDB search API. Deduplicates by `(title, isMovie)` before hitting the API. Rate-limited to ~4 req/sec.
 5. `tvlogo.Client.Resolve` replaces Gracenote channel icons with verified PNGs from `github.com/tv-logo/tv-logos`. Generates candidate URL slugs from callsign/affiliate name and HEAD-checks each (rate-limited to ~5 req/sec).
 6. `fixDeadImageURLs` rewrites `zap2it.tmsimg.com` → `tmsimg.com` for broken Gracenote image URLs.
@@ -43,7 +43,7 @@ The binary is a single Go process that scrapes GraceNote/TMS for 14 days of TV l
 
 | Cache | File | TTL |
 |---|---|---|
-| Guide (in-memory + disk) | `guide_cache.json` | 4h (startup skip) / 24h (rescrape) |
+| Guide (in-memory + disk) | `guide_cache.json` | 4h (startup skip) / 24h (rescrape); carries a schema version, older caches are rebuilt once |
 | TMDB lookups | `tmdb_cache.json` | 7 days |
 | TV logo HEAD checks | `tvlogo_cache.json` | persisted, no expiry |
 | Image proxy | `image_cache/` dir | indefinite (per-URL SHA256 key) |
diff --git a/README.md b/README.md
index ae97626..cb7664c 100644
--- a/README.md
+++ b/README.md
@@ -118,6 +118,7 @@ A saved `CONFIG_PATH` selection takes precedence over legacy `GN_*` settings. De
 | `POST /api/setup/provider` | Save the selected provider and queue a fresh guide |
 | `GET /xmlguide.xmltv` | XMLTV guide data (point your DVR here) |
 | `GET /api/guide.json` | Guide data as JSON |
+| `GET /api/lineup.json` | Every channel position in the active provider lineup as JSON (see below) |
 | `GET /` | The Grid — built-in web UI |
 | `GET /img?url=...` | Image proxy with local cache |
 | `GET /api/livetv/config` | Returns `{"enabled":true/false}` — whether Jellyfin live TV is configured |
@@ -125,6 +126,41 @@ A saved `CONFIG_PATH` selection takes precedence over legacy `GN_*` settings. De
 | `GET /api/livetv/tune?id=<channelId>` | Starts a live stream for the given channel and returns an HLS URL |
 | `POST /api/livetv/stop` | Forwards a playback-stop notification to Jellyfin to end a live stream |
 
+### Lineup JSON
+
+`/api/lineup.json` describes the provider lineup itself rather than the schedule: one entry per channel number, never collapsed, so a station carried at two numbers appears twice. It returns `503` with a `Retry-After` header until the first guide has been built.
+
+```json
+{
+  "generated": "2026-09-13T04:10:22Z",
+  "source": {
+    "providerName": "Local Over the Air Broadcast",
+    "providerType": "OTA",
+    "location": "",
+    "lineupId": "USA-lineupId-DEFAULT",
+    "headendId": "lineupId",
+    "postalCode": "13490",
+    "country": "USA",
+    "device": "-",
+    "language": "en-us"
+  },
+  "positions": [
+    {
+      "number": "2.1",
+      "stationId": "53158",
+      "placementId": "531580",
+      "callSign": "WKTVDT",
+      "affiliate": "NATIONAL BROADCASTING COMPANY",
+      "affiliateCallSign": "",
+      "filters": ["sports", "news"],
+      "logoUrl": "https://raw.githubusercontent.com/tv-logo/tv-logos/main/countries/united-states/nbc-us.png"
+    }
+  ]
+}
+```
+
+`filters` are Gracenote's own station tags with the `filter-` prefix removed. `placementId` is Gracenote's row identifier and is not stable across scrapes; use `number` plus `stationId` to identify a position. `providerName`, `providerType`, and `location` are filled from the saved setup when it matches the lineup the guide was built from.
+
 ## The Grid
 
 The server includes a built-in retro-styled TV guide web UI at the root URL. If no provider is configured, `/` redirects to `/setup`. Once configured, the guide auto-scrolls through your channel lineup and shows program details, posters, and metadata. Handy for a quick glance at what's on without opening your DVR app.
diff --git a/lineup_handler_test.go b/lineup_handler_test.go
new file mode 100644
index 0000000..5e4b17c
--- /dev/null
+++ b/lineup_handler_test.go
@@ -0,0 +1,195 @@
+package main
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"path/filepath"
+	"reflect"
+	"sort"
+	"testing"
+	"time"
+
+	"github.com/daniel-widrick/GraceNoteScraper/appconfig"
+	"github.com/daniel-widrick/GraceNoteScraper/guide"
+)
+
+func lineupTestConfig() appconfig.Config {
+	return appconfig.Config{
+		Version: appconfig.CurrentVersion,
+		Gracenote: appconfig.GracenoteConfig{
+			Country: "USA", PostalCode: "13490", Language: "en-us", ProviderType: "OTA", Device: "-",
+			LineupID: "USA-lineupId-DEFAULT", ProviderName: "Local Over the Air Broadcast", Location: "Utica", HeadendID: "lineupId",
+		},
+	}
+}
+
+func lineupTestGuide() *guide.TVGuide {
+	return &guide.TVGuide{
+		Lineup: []guide.LineupPosition{
+			{ChannelNo: "10", StationID: "s10", PlacementID: "s100", CallSign: "TEN", Affiliate: "Ten Net", Filters: []string{"news"}, LogoURL: "http://logo/ten.png"},
+			{ChannelNo: "2.1", StationID: "s2", PlacementID: "s20", CallSign: "TWO", Affiliate: "Two Net", AffiliateCallSign: "TW"},
+			{ChannelNo: "1002", StationID: "s2", PlacementID: "s299", CallSign: "TWO", Affiliate: "Two Net", AffiliateCallSign: "TW"},
+		},
+		Source: guide.Source{
+			Country: "USA", PostalCode: "13490", HeadendID: "lineupId", LineupID: "USA-lineupId-DEFAULT", Device: "-", Language: "en-us",
+			GeneratedAt: time.Date(2026, 9, 13, 4, 10, 22, 0, time.UTC),
+		},
+	}
+}
+
+func newLineupServer(t *testing.T, g *guide.TVGuide, save bool) http.Handler {
+	t.Helper()
+	store, err := appconfig.LoadStore(filepath.Join(t.TempDir(), "config.json"))
+	if err != nil {
+		t.Fatalf("LoadStore: %v", err)
+	}
+	if save {
+		if err := store.Save(lineupTestConfig()); err != nil {
+			t.Fatalf("Save: %v", err)
+		}
+	}
+	state := &GuideState{}
+	state.Update(g)
+	return handleLineupJSON(state, store)
+}
+
+func TestLineupJSONUnavailableBeforeFirstGuide(t *testing.T) {
+	rec := httptest.NewRecorder()
+	newLineupServer(t, nil, true).ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/api/lineup.json", nil))
+	if rec.Code != http.StatusServiceUnavailable {
+		t.Fatalf("status = %d", rec.Code)
+	}
+	if rec.Header().Get("Retry-After") != "30" {
+		t.Fatalf("Retry-After = %q", rec.Header().Get("Retry-After"))
+	}
+}
+
+func TestLineupJSONResponse(t *testing.T) {
+	rec := httptest.NewRecorder()
+	newLineupServer(t, lineupTestGuide(), true).ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/api/lineup.json", nil))
+	if rec.Code != http.StatusOK {
+		t.Fatalf("status = %d body = %s", rec.Code, rec.Body.String())
+	}
+	if ct := rec.Header().Get("Content-Type"); ct != "application/json" {
+		t.Errorf("Content-Type = %q", ct)
+	}
+	if rec.Header().Get("Access-Control-Allow-Origin") != "*" {
+		t.Error("CORS header missing")
+	}
+
+	var got APILineup
+	if err := json.Unmarshal(rec.Body.Bytes(), &got); err != nil {
+		t.Fatalf("decode: %v", err)
+	}
+	if got.Generated != "2026-09-13T04:10:22Z" {
+		t.Errorf("generated = %q", got.Generated)
+	}
+	wantSource := APILineupSource{
+		ProviderName: "Local Over the Air Broadcast", ProviderType: "OTA", Location: "Utica",
+		LineupID: "USA-lineupId-DEFAULT", HeadendID: "lineupId", PostalCode: "13490", Country: "USA", Device: "-", Language: "en-us",
+	}
+	if got.Source != wantSource {
+		t.Errorf("source = %+v\nwant %+v", got.Source, wantSource)
+	}
+
+	var numbers []string
+	for _, p := range got.Positions {
+		numbers = append(numbers, p.Number)
+	}
+	if !reflect.DeepEqual(numbers, []string{"2.1", "10", "1002"}) {
+		t.Errorf("positions not sorted by number: %v", numbers)
+	}
+	ten := got.Positions[1]
+	want := APILineupPosition{Number: "10", StationID: "s10", PlacementID: "s100", CallSign: "TEN", Affiliate: "Ten Net", Filters: []string{"news"}, LogoURL: "http://logo/ten.png"}
+	if !reflect.DeepEqual(ten, want) {
+		t.Errorf("position = %+v\nwant %+v", ten, want)
+	}
+	if got.Positions[0].StationID != "s2" || got.Positions[2].StationID != "s2" {
+		t.Error("the same station at two numbers must appear twice")
+	}
+}
+
+func TestLineupJSONKeySetIsStable(t *testing.T) {
+	rec := httptest.NewRecorder()
+	newLineupServer(t, lineupTestGuide(), true).ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/api/lineup.json", nil))
+
+	var raw map[string]json.RawMessage
+	if err := json.Unmarshal(rec.Body.Bytes(), &raw); err != nil {
+		t.Fatal(err)
+	}
+	if keys := sortedKeys(raw); !reflect.DeepEqual(keys, []string{"generated", "positions", "source"}) {
+		t.Errorf("top-level keys = %v", keys)
+	}
+	var source map[string]json.RawMessage
+	if err := json.Unmarshal(raw["source"], &source); err != nil {
+		t.Fatal(err)
+	}
+	if keys := sortedKeys(source); !reflect.DeepEqual(keys, []string{"country", "device", "headendId", "language", "lineupId", "location", "postalCode", "providerName", "providerType"}) {
+		t.Errorf("source keys = %v", keys)
+	}
+	var positions []map[string]json.RawMessage
+	if err := json.Unmarshal(raw["positions"], &positions); err != nil {
+		t.Fatal(err)
+	}
+	// Position with filters carries the filters key; one without omits it.
+	withFilters := sortedKeys(positions[1])
+	if !reflect.DeepEqual(withFilters, []string{"affiliate", "affiliateCallSign", "callSign", "filters", "logoUrl", "number", "placementId", "stationId"}) {
+		t.Errorf("position keys = %v", withFilters)
+	}
+	if _, ok := positions[0]["filters"]; ok {
+		t.Error("filters should be omitted when empty")
+	}
+	if _, ok := positions[0]["logoUrl"]; !ok {
+		t.Error("logoUrl must always be present, even when empty")
+	}
+}
+
+func TestLineupJSONSourceNamingRequiresMatchingConfig(t *testing.T) {
+	// No saved configuration at all.
+	rec := httptest.NewRecorder()
+	newLineupServer(t, lineupTestGuide(), false).ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/api/lineup.json", nil))
+	var got APILineup
+	if err := json.Unmarshal(rec.Body.Bytes(), &got); err != nil {
+		t.Fatal(err)
+	}
+	if got.Source.ProviderName != "" || got.Source.ProviderType != "" || got.Source.Location != "" {
+		t.Errorf("provider naming should be blank without config: %+v", got.Source)
+	}
+	if got.Source.LineupID != "USA-lineupId-DEFAULT" {
+		t.Errorf("guide source fields must still be present: %+v", got.Source)
+	}
+
+	// Saved configuration describes a different lineup than the guide.
+	g := lineupTestGuide()
+	g.Source.LineupID = "USA-OTHER-DEFAULT"
+	rec = httptest.NewRecorder()
+	newLineupServer(t, g, true).ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/api/lineup.json", nil))
+	if err := json.Unmarshal(rec.Body.Bytes(), &got); err != nil {
+		t.Fatal(err)
+	}
+	if got.Source.ProviderName != "" {
+		t.Errorf("provider name leaked across lineups: %+v", got.Source)
+	}
+	if got.Source.LineupID != "USA-OTHER-DEFAULT" {
+		t.Errorf("lineup id should come from the guide: %+v", got.Source)
+	}
+}
+
+func TestLineupJSONDoesNotMutateGuideOrder(t *testing.T) {
+	g := lineupTestGuide()
+	before := append([]guide.LineupPosition(nil), g.Lineup...)
+	lineupToJSON(g, lineupTestConfig(), true)
+	if !reflect.DeepEqual(before, g.Lineup) {
+		t.Fatal("lineupToJSON must sort a copy, not the live guide")
+	}
+}
+
+func sortedKeys(m map[string]json.RawMessage) []string {
+	keys := make([]string, 0, len(m))
+	for k := range m {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+	return keys
+}
diff --git a/main.go b/main.go
index 8f9424f..0197102 100644
--- a/main.go
+++ b/main.go
@@ -87,6 +87,37 @@ type APIProgram struct {
 	Description string `json:"description,omitempty"`
 }
 
+// APILineup is the response shape of /api/lineup.json: every provider
+// position for the active lineup, plus the source it came from.
+type APILineup struct {
+	Generated string              `json:"generated"`
+	Source    APILineupSource     `json:"source"`
+	Positions []APILineupPosition `json:"positions"`
+}
+
+type APILineupSource struct {
+	ProviderName string `json:"providerName"`
+	ProviderType string `json:"providerType"`
+	Location     string `json:"location"`
+	LineupID     string `json:"lineupId"`
+	HeadendID    string `json:"headendId"`
+	PostalCode   string `json:"postalCode"`
+	Country      string `json:"country"`
+	Device       string `json:"device"`
+	Language     string `json:"language"`
+}
+
+type APILineupPosition struct {
+	Number            string   `json:"number"`
+	StationID         string   `json:"stationId"`
+	PlacementID       string   `json:"placementId"`
+	CallSign          string   `json:"callSign"`
+	Affiliate         string   `json:"affiliate"`
+	AffiliateCallSign string   `json:"affiliateCallSign"`
+	Filters           []string `json:"filters,omitempty"`
+	LogoURL           string   `json:"logoUrl"`
+}
+
 // ---------- Conversion ----------
 
 // guideToJSON converts a TVGuide into the simplified JSON API format.
@@ -154,6 +185,56 @@ func guideToJSON(g *guide.TVGuide) APIGuide {
 	}
 }
 
+// lineupToJSON converts a guide's lineup into the API shape. Provider naming
+// comes from the saved configuration only when it describes the same source
+// the guide was built from.
+func lineupToJSON(g *guide.TVGuide, config appconfig.Config, configured bool) APILineup {
+	positions := make([]guide.LineupPosition, len(g.Lineup))
+	copy(positions, g.Lineup)
+	guide.SortLineup(positions)
+
+	out := APILineup{
+		Generated: g.Source.GeneratedAt.UTC().Format(time.RFC3339),
+		Source: APILineupSource{
+			LineupID:   g.Source.LineupID,
+			HeadendID:  g.Source.HeadendID,
+			PostalCode: g.Source.PostalCode,
+			Country:    g.Source.Country,
+			Device:     g.Source.Device,
+			Language:   g.Source.Language,
+		},
+		Positions: make([]APILineupPosition, 0, len(positions)),
+	}
+	if g.Source.GeneratedAt.IsZero() {
+		out.Generated = time.Now().UTC().Format(time.RFC3339)
+	}
+	if configured && sourceMatchesConfig(g.Source, config) {
+		out.Source.ProviderName = config.Gracenote.ProviderName
+		out.Source.ProviderType = config.Gracenote.ProviderType
+		out.Source.Location = config.Gracenote.Location
+	}
+	for _, p := range positions {
+		out.Positions = append(out.Positions, APILineupPosition{
+			Number:            p.ChannelNo,
+			StationID:         p.StationID,
+			PlacementID:       p.PlacementID,
+			CallSign:          p.CallSign,
+			Affiliate:         p.Affiliate,
+			AffiliateCallSign: p.AffiliateCallSign,
+			Filters:           p.Filters,
+			LogoURL:           p.LogoURL,
+		})
+	}
+	return out
+}
+
+// sourceMatchesConfig reports whether a guide was built from the configured lineup.
+func sourceMatchesConfig(src guide.Source, config appconfig.Config) bool {
+	p := config.Preferences()
+	return src.LineupID == p.LineupId && src.HeadendID == p.Headend && src.PostalCode == p.ZipCode &&
+		src.Country == p.Country && src.Device == p.Device && src.Language == p.Language
+}
+
 // xmltvTimeToISO converts "20250225200000 +0000" → "2025-02-25T20:00:00Z"
 func xmltvTimeToISO(xmltvTime string) string {
 	xmltvTime = strings.TrimSpace(xmltvTime)
@@ -607,6 +688,24 @@ func handleGuideJSON(state *GuideState) http.HandlerFunc {
 	}
 }
 
+func handleLineupJSON(state *GuideState, store *appconfig.Store) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		g := state.Get()
+		if g == nil {
+			w.Header().Set("Retry-After", "30")
+			http.Error(w, "Guide is being generated", http.StatusServiceUnavailable)
+			return
+		}
+
+		config, configured, _ := store.Get()
+		w.Header().Set("Content-Type", "application/json")
+		w.Header().Set("Access-Control-Allow-Origin", "*")
+		enc := json.NewEncoder(w)
+		enc.SetEscapeHTML(false)
+		enc.Encode(lineupToJSON(g, config, configured))
+	}
+}
+
 // ---------- Image proxy ----------
 
 const imageCacheDir = "image_cache"
@@ -1115,6 +1214,7 @@ func main() {
 	mux.HandleFunc("/api/setup/status", setupHandlers.handleScrapeStatus)
 	mux.HandleFunc("/xmlguide.xmltv", handleXMLTV(state))
 	mux.HandleFunc("/api/guide.json", handleGuideJSON(state))
+	mux.HandleFunc("/api/lineup.json", handleLineupJSON(state, configStore))
 	mux.HandleFunc("/img", handleImage)
 	mux.HandleFunc("/api/livetv/config", handleLiveTVConfig(jellyfinURL, jellyfinAPIKey))
 	if jellyfinURL != "" && jellyfinAPIKey != "" {