diff --git a/FuelBoard/FavouritesView.swift b/FuelBoard/FavouritesView.swift
index 6c4abd6..b9f7d92 100644
--- a/FuelBoard/FavouritesView.swift
+++ b/FuelBoard/FavouritesView.swift
@@ -48,6 +48,14 @@ struct FavouritesView: View {
     /// Trends sheet (price history chart) presentation state.
     @State private var showTrends = false
 
+    /// The Key (legend) sheet — the same sheet the Stations tab presents, opened
+    /// from the info button beside Edit.
+    @State private var showKey = false
+    /// The Key sheet's two nested sheets, owned here because its rows set them
+    /// (same arrangement as StationsView, so the QA hooks behave identically).
+    @State private var showBestValueInfo = false
+    @State private var showImportantInformation = false
+
     /// Station picked for the More-info sheet (tap action = showDetails).
     @State private var detailStation: FuelStation?
 
@@ -206,8 +214,8 @@ struct FavouritesView: View {
             }
             .navigationTitle(String(localized: "Favourites", comment: "Favourites tab title"))
             .toolbar {
-                if !favourites.isEmpty {
-                    ToolbarItemGroup(placement: .topBarTrailing) {
+                ToolbarItemGroup(placement: .topBarTrailing) {
+                    if !favourites.isEmpty {
                         Button {
                             showTrends = true
                         } label: {
@@ -216,8 +224,25 @@ struct FavouritesView: View {
                         }
                         EditButton()
                     }
+                    // Same button and same slot as the Stations tab: last in the
+                    // group, so it sits to the right of Edit. Shown even with no
+                    // favourites — the legend explains the prices and labels, which
+                    // matter before anything is starred.
+                    Button {
+                        showKey = true
+                    } label: {
+                        Image(systemName: "info.circle")
+                    }
+                    .accessibilityLabel(String(localized: "Key", comment: "Key button accessibility label"))
                 }
             }
+            .sheet(isPresented: $showKey) {
+                KeySheetView(
+                    fuelTint: activeFuel.tintColor,
+                    showBestValueInfo: $showBestValueInfo,
+                    showImportantInformation: $showImportantInformation
+                )
+            }
             .sheet(isPresented: $showTrends) {
                 TrendsView(
                     favourites: favourites,
diff --git a/FuelBoard/StationsView.swift b/FuelBoard/StationsView.swift
index cc87de8..f7ca052 100644
--- a/FuelBoard/StationsView.swift
+++ b/FuelBoard/StationsView.swift
@@ -1,6 +1,94 @@
 import SwiftUI
 import WidgetKit
 
+/// The "Key" legend: price ratings, savings capsules, station labels, the
+/// favourite glyph, then the two deeper explanations. One sheet for both list
+/// tabs — Stations opens it from the info button in the navigation bar,
+/// Favourites from the button beside Edit — so the legend cannot drift between
+/// them.
+///
+/// Dismisses through the environment rather than the presenting view's state, and
+/// takes the two nested-sheet flags as bindings, so each tab keeps owning its own
+/// QA launch-argument hooks.
+struct KeySheetView: View {
+    /// The selected fuel's colour. `KeyStationLabelIndicator` draws its pump badge
+    /// in it, so the legend matches the rows the reader is looking at.
+    let fuelTint: Color
+    @Binding var showBestValueInfo: Bool
+    @Binding var showImportantInformation: Bool
+
+    @Environment(\.dismiss) private var dismiss
+
+    var body: some View {
+        NavigationStack {
+            List {
+                Section {
+                    KeySheetDescriptionRow(item: KeySheetContent.priceRatings[0]) {
+                        KeyPriceRatingIndicator(item: KeySheetContent.priceRatings[0], color: .green)
+                    }
+                    KeySheetDescriptionRow(item: KeySheetContent.priceRatings[1]) {
+                        KeyPriceRatingIndicator(item: KeySheetContent.priceRatings[1], color: .orange)
+                    }
+                    KeySheetDescriptionRow(item: KeySheetContent.priceRatings[2]) {
+                        KeyPriceRatingIndicator(item: KeySheetContent.priceRatings[2], color: .red)
+                    }
+                } header: {
+                    Text("Price ratings")
+                }
+
+                Section {
+                    ForEach(KeySheetContent.savings, id: \.label) { item in
+                        KeySheetDescriptionRow(item: item) {
+                            KeySavingsCapsule(label: item.label)
+                        }
+                    }
+                } header: {
+                    Text("Savings")
+                }
+
+                Section {
+                    ForEach(KeySheetContent.stationLabels, id: \.label) { item in
+                        KeySheetDescriptionRow(item: item) {
+                            KeyStationLabelIndicator(label: item.label, fuelColor: fuelTint)
+                        }
+                    }
+                } header: {
+                    Text("Station labels")
+                }
+
+                Section {
+                    KeySheetDescriptionRow(item: KeySheetContent.favourite) {
+                        FavouriteStarGlyph(isFavourite: true)
+                    }
+                } header: {
+                    Text("Favourites")
+                }
+
+                Section {
+                    HowBestValueRow { showBestValueInfo = true }
+                }
+
+                Section {
+                    ImportantInformationRow { showImportantInformation = true }
+                }
+            }
+            .navigationTitle("Key")
+            .navigationBarTitleDisplayMode(.inline)
+            .toolbar {
+                ToolbarItem(placement: .confirmationAction) {
+                    Button("Done") { dismiss() }
+                }
+            }
+            // Nested sheet: the Key sheet stays behind the explanation.
+            .sheet(isPresented: $showBestValueInfo) { HowBestValueSheet() }
+            // Nested sheet: the Key sheet stays behind the disclaimer.
+            .importantInformationSheet(isPresented: $showImportantInformation)
+        }
+        .presentationDetents([.fraction(0.6), .large])
+        .presentationBackground(Color(UIColor.systemGroupedBackground))
+    }
+}
+
 /// Stations tab — the main list with fuel picker, distance filter, sort, pagination.
 struct StationsView: View {
     let stations: [FuelStation]
@@ -296,73 +384,15 @@ struct StationsView: View {
         )
     }
 
+    /// The legend sheet, shared with the Favourites tab. Only the fuel differs:
+    /// its colour tints the station-label row, so the legend matches the rows the
+    /// reader is actually looking at.
     private var keySheet: some View {
-        NavigationStack {
-            List {
-                Section {
-                    KeySheetDescriptionRow(item: KeySheetContent.priceRatings[0]) {
-                        KeyPriceRatingIndicator(item: KeySheetContent.priceRatings[0], color: .green)
-                    }
-                    KeySheetDescriptionRow(item: KeySheetContent.priceRatings[1]) {
-                        KeyPriceRatingIndicator(item: KeySheetContent.priceRatings[1], color: .orange)
-                    }
-                    KeySheetDescriptionRow(item: KeySheetContent.priceRatings[2]) {
-                        KeyPriceRatingIndicator(item: KeySheetContent.priceRatings[2], color: .red)
-                    }
-                } header: {
-                    Text("Price ratings")
-                }
-
-                Section {
-                    ForEach(KeySheetContent.savings, id: \.label) { item in
-                        KeySheetDescriptionRow(item: item) {
-                            KeySavingsCapsule(label: item.label)
-                        }
-                    }
-                } header: {
-                    Text("Savings")
-                }
-
-                Section {
-                    ForEach(KeySheetContent.stationLabels, id: \.label) { item in
-                        KeySheetDescriptionRow(item: item) {
-                            KeyStationLabelIndicator(label: item.label, fuelColor: selectedFuel.tintColor)
-                        }
-                    }
-                } header: {
-                    Text("Station labels")
-                }
-
-                Section {
-                    KeySheetDescriptionRow(item: KeySheetContent.favourite) {
-                        FavouriteStarGlyph(isFavourite: true)
-                    }
-                } header: {
-                    Text("Favourites")
-                }
-
-                Section {
-                    HowBestValueRow { showBestValueInfo = true }
-                }
-
-                Section {
-                    ImportantInformationRow { showImportantInformation = true }
-                }
-            }
-            .navigationTitle("Key")
-            .navigationBarTitleDisplayMode(.inline)
-            .toolbar {
-                ToolbarItem(placement: .confirmationAction) {
-                    Button("Done") { showKey = false }
-                }
-            }
-            // Nested sheet: the Key sheet stays behind the explanation.
-            .sheet(isPresented: $showBestValueInfo) { HowBestValueSheet() }
-            // Nested sheet: the Key sheet stays behind the disclaimer.
-            .importantInformationSheet(isPresented: $showImportantInformation)
-        }
-        .presentationDetents([.fraction(0.6), .large])
-        .presentationBackground(Color(UIColor.systemGroupedBackground))
+        KeySheetView(
+            fuelTint: selectedFuel.tintColor,
+            showBestValueInfo: $showBestValueInfo,
+            showImportantInformation: $showImportantInformation
+        )
     }
 
     private func stationRow(_ station: FuelStation) -> some View {