diff --git a/lib/signs/bus.ex b/lib/signs/bus.ex
index a87a75e77..d7a09e6fe 100644
--- a/lib/signs/bus.ex
+++ b/lib/signs/bus.ex
@@ -121,6 +121,10 @@ defmodule Signs.Bus do
     {:ok, state}
   end
 
+  @type content_values ::
+          {messages :: [Content.Message.value()], audios :: [Content.Audio.value()],
+           tts_audios :: [Content.Audio.tts_value()]}
+
   @impl true
   def handle_info(:run_loop, state) do
     Process.send_after(self(), :run_loop, 1000)
@@ -165,10 +169,10 @@ defmodule Signs.Bus do
       |> Enum.group_by(&{&1.stop_id, &1.route_id, &1.direction_id})
 
     # Compute new sign text and audio
-    {[top, bottom], audios} =
+    {[top, bottom], audios, tts_audios} =
       cond do
         config == :off ->
-          {["", ""], []}
+          {_messages = ["", ""], _audios = [], _tts_audios = []}
 
         match?({:static_text, _}, config) ->
           static_text_content(
@@ -225,12 +229,16 @@ defmodule Signs.Bus do
     end)
     |> then(fn state ->
       if should_read?(current_time, state) do
-        send_audio(audios, state)
+        send_audio(audios, tts_audios, state)
         %{state | last_read_time: current_time}
       else
         if should_announce_drawbridge?(bridge_status, bridge_enabled?, current_time, state) do
-          bridge_audio(bridge_status, bridge_enabled?, current_time, state)
-          |> send_audio(state)
+          bridge_audios = bridge_audio(bridge_status, bridge_enabled?, current_time, state)
+
+          bridge_tts_audios =
+            bridge_tts_audio(bridge_status, bridge_enabled?, current_time, state)
+
+          send_audio(bridge_audios, bridge_tts_audios, state)
         end
 
         state
@@ -292,6 +300,15 @@ defmodule Signs.Bus do
   end
 
   # Static text mode. Just display the configured text, and possibly the bridge message.
+  @spec static_text_content(
+          Engine.Config.sign_config(),
+          term(),
+          boolean(),
+          DateTime.t(),
+          map(),
+          map(),
+          t()
+        ) :: content_values()
   defp static_text_content(
          config,
          bridge_status,
@@ -321,11 +338,15 @@ defmodule Signs.Bus do
       [{:ad_hoc, {"#{line1} #{line2}", :audio}}]
       |> Enum.concat(bridge_audio(bridge_status, bridge_enabled?, current_time, state))
 
-    {messages, audios}
+    tts_audios = [{"#{line1} #{line2}", nil}]
+
+    {messages, audios, tts_audios}
   end
 
   # Platform mode. Display one prediction per route, but if all the predictions are for the
   # same route, then show a single page of two.
+  @spec platform_mode_content(map(), map(), map(), DateTime.t(), term(), boolean(), t()) ::
+          content_values()
   defp platform_mode_content(
          predictions_lookup,
          route_alerts_lookup,
@@ -390,11 +411,30 @@ defmodule Signs.Bus do
         |> paginate_audio()
         |> Enum.concat(bridge_audio(bridge_status, bridge_enabled?, current_time, state))
 
-      {messages, audios}
+      tts_audios =
+        case audio_content do
+          [] ->
+            []
+
+          [single] ->
+            [long_message_tts_audio(single, current_time, state)]
+
+          list ->
+            Enum.map(list, &message_tts_audio(&1, current_time, state))
+            |> Enum.join(" ")
+            |> add_tts_preamble()
+            |> List.wrap()
+        end
+        |> Enum.map(&{&1, nil})
+        |> Enum.concat(bridge_tts_audio(bridge_status, bridge_enabled?, current_time, state))
+
+      {messages, audios, tts_audios}
     end
   end
 
   # Mezzanine mode. Display and paginate each line separately.
+  @spec mezzanine_mode_content(map(), map(), map(), DateTime.t(), term(), boolean(), t()) ::
+          content_values()
   defp mezzanine_mode_content(
          predictions_lookup,
          route_alerts_lookup,
@@ -429,20 +469,38 @@ defmodule Signs.Bus do
         |> paginate_audio()
         |> Enum.concat(bridge_audio(bridge_status, bridge_enabled?, current_time, state))
 
-      {messages, audios}
+      tts_audios =
+        case top_content ++ bottom_content do
+          [] ->
+            []
+
+          list ->
+            Enum.map(list, &message_tts_audio(&1, current_time, state))
+            |> Enum.join(" ")
+            |> add_tts_preamble()
+            |> List.wrap()
+        end
+        |> Enum.map(&{&1, nil})
+        |> Enum.concat(bridge_tts_audio(bridge_status, bridge_enabled?, current_time, state))
+
+      {messages, audios, tts_audios}
     end
   end
 
+  @spec special_harvard_content() :: content_values()
   defp special_harvard_content() do
     messages = ["Board routes 71", "and 73 on upper level"]
     audios = paginate_audio([:board_routes_71_and_73_on_upper_level])
-    {messages, audios}
+    tts_audios = [{"Board routes 71 and 73 on upper level", nil}]
+    {messages, audios, tts_audios}
   end
 
+  @spec no_service_content() :: content_values()
   defp no_service_content do
     messages = paginate_pairs([["No bus service", ""]])
     audios = paginate_audio([:no_bus_service])
-    {messages, audios}
+    tts_audios = [{"No bus service", nil}]
+    {messages, audios, tts_audios}
   end
 
   defp configs_content(nil, _, _), do: []
@@ -612,6 +670,36 @@ defmodule Signs.Bus do
     end
   end
 
+  defp bridge_tts_audio(bridge_status, bridge_enabled?, current_time, state) do
+    %{chelsea_bridge: chelsea_bridge} = state
+
+    if bridge_enabled? && chelsea_bridge &&
+         bridge_status_raised?(bridge_status, current_time) do
+      {duration, duration_spanish} =
+        case bridge_status_minutes(bridge_status, current_time) do
+          minutes when minutes < 2 ->
+            {"We expect it to be lowered soon.", "Esperamos que se baje pronto."}
+
+          minutes ->
+            {"We expect this to last for at least #{minutes} more minutes.",
+             "Esperamos que esto dure al menos #{minutes} minutos más."}
+        end
+
+      english_text =
+        "The Chelsea Street bridge is raised. #{duration} SL3 buses may be delayed, detoured, or turned back."
+
+      spanish_text =
+        "El puente de Chelsea Street está levantado. #{duration_spanish} Los autobuses SL3 pueden sufrir retrasos, desvíos o dar marcha atrás."
+
+      [
+        {english_text, PaEss.Utilities.paginate_text(english_text)},
+        {spanish_text, PaEss.Utilities.paginate_text(spanish_text)}
+      ]
+    else
+      []
+    end
+  end
+
   defp format_message(nil, _, _, _state), do: ""
 
   defp format_message({:predictions, [first | _]}, other, current_time, _state) do
@@ -742,6 +830,8 @@ defmodule Signs.Bus do
   defp add_preamble([]), do: []
   defp add_preamble(items), do: [[:upcoming_departures] | items]
 
+  defp add_tts_preamble(str), do: "Upcoming departures: " <> str
+
   # Returns a list of audio tokens describing the given message.
   defp message_audio({:predictions, [prediction | _]}, current_time, _state) do
     route =
@@ -774,6 +864,34 @@ defmodule Signs.Bus do
     route ++ [{:headsign, headsign}, :no_service]
   end
 
+  defp message_tts_audio({:predictions, [prediction | _]}, current_time, _state) do
+    route =
+      case PaEss.Utilities.prediction_route_name(prediction) do
+        nil -> ""
+        name -> "Route #{name}, "
+      end
+
+    time =
+      case prediction_minutes(prediction, current_time) do
+        0 -> "arriving"
+        1 -> "1 minute"
+        m -> "#{m} minutes"
+      end
+
+    "#{route}#{prediction.headsign}, #{time}."
+  end
+
+  defp message_tts_audio({:alert, config}, _, state) do
+    route =
+      case config_route_name(config) do
+        nil -> ""
+        name -> "Route #{name}, "
+      end
+
+    headsign = config_headsign(config, state)
+    "#{route}#{headsign}, no service."
+  end
+
   # Returns a list of audio tokens representing the special "long form" description of
   # the given prediction.
   defp long_message_audio({:predictions, predictions}, current_time, _state) do
@@ -812,6 +930,38 @@ defmodule Signs.Bus do
     [Enum.concat([[:there_is_no], route, [:bus_service_to, {:headsign, headsign}]])]
   end
 
+  defp long_message_tts_audio({:predictions, predictions}, current_time, _state) do
+    Stream.take(predictions, 2)
+    |> Enum.zip_with(["next", "following"], fn prediction, next_or_following ->
+      route =
+        case PaEss.Utilities.prediction_route_name(prediction) do
+          nil -> ""
+          name -> "route #{name} "
+        end
+
+      time =
+        case prediction_minutes(prediction, current_time) do
+          0 -> "is now arriving"
+          1 -> "arrives in 1 minute"
+          m -> "arrives in #{m} minutes"
+        end
+
+      "The #{next_or_following} #{route}bus to #{prediction.headsign} #{time}."
+    end)
+    |> Enum.join(" ")
+  end
+
+  defp long_message_tts_audio({:alert, config}, _, state) do
+    route =
+      case config_route_name(config) do
+        nil -> ""
+        name -> "route #{name} "
+      end
+
+    headsign = config_headsign(config, state)
+    "There is no #{route}bus service to #{headsign}."
+  end
+
   # Turns a list of audio tokens into a list of audio messages, chunking as needed to stay under
   # the max var limit.
   defp paginate_audio(items) do
@@ -828,15 +978,14 @@ defmodule Signs.Bus do
     end)
   end
 
-  defp send_audio(audios, state) do
+  defp send_audio(audios, tts_audios, state) do
     %{audio_zones: audio_zones, sign_updater: sign_updater} = state
 
     if audios != [] && audio_zones != [] do
       sign_updater.play_message(
         state,
         audios,
-        # TODO: Implement TTS for bus audio
-        [],
+        tts_audios,
         Enum.map(audios, fn _ -> [message_type: "Bus"] end)
       )
     end
diff --git a/test/signs/bus_test.exs b/test/signs/bus_test.exs
index 5507f8a02..404a1a68f 100644
--- a/test/signs/bus_test.exs
+++ b/test/signs/bus_test.exs
@@ -127,29 +127,35 @@ defmodule Signs.BusTest do
     test "platform mode, top two" do
       expect_messages(["14 WakfldAv  2 min", "14 WakfldAv 11 min"])
 
-      expect_audios([
-        {:canned,
-         {"119",
-          [
-            "501",
-            "575",
-            "859",
-            "621",
-            "503",
-            "504",
-            "5502",
-            "505",
-            "21012",
-            "667",
-            "575",
-            "859",
-            "621",
-            "503",
-            "504",
-            "5511",
-            "505"
-          ], :audio}}
-      ])
+      expect_audios(
+        [
+          {:canned,
+           {"119",
+            [
+              "501",
+              "575",
+              "859",
+              "621",
+              "503",
+              "504",
+              "5502",
+              "505",
+              "21012",
+              "667",
+              "575",
+              "859",
+              "621",
+              "503",
+              "504",
+              "5511",
+              "505"
+            ], :audio}}
+        ],
+        [
+          {"The next route 14 bus to Wakefield Ave arrives in 2 minutes. The following route 14 bus to Wakefield Ave arrives in 11 minutes.",
+           nil}
+        ]
+      )
 
       state =
         Map.merge(@sign_state, %{
@@ -165,27 +171,33 @@ defmodule Signs.BusTest do
         [{"Chelsea      4 min", 6}, {"", 6}]
       ])
 
-      expect_audios([
-        {:canned,
-         {"117",
-          [
-            "548",
-            "21012",
-            "575",
-            "621",
-            "5502",
-            "505",
-            "21012",
-            "860",
-            "5504",
-            "505",
-            "21012",
-            "678",
-            "605",
-            "5507",
-            "505"
-          ], :audio}}
-      ])
+      expect_audios(
+        [
+          {:canned,
+           {"117",
+            [
+              "548",
+              "21012",
+              "575",
+              "621",
+              "5502",
+              "505",
+              "21012",
+              "860",
+              "5504",
+              "505",
+              "21012",
+              "678",
+              "605",
+              "5507",
+              "505"
+            ], :audio}}
+        ],
+        [
+          {"Upcoming departures: Route 14, Wakefield Ave, 2 minutes. Chelsea, 4 minutes. Route 34, Clarendon Hill, 7 minutes.",
+           nil}
+        ]
+      )
 
       state =
         Map.merge(@sign_state, %{
@@ -202,12 +214,18 @@ defmodule Signs.BusTest do
     test "mezzanine mode" do
       expect_messages(["SL5 Nubian   8 min", "14 WakefldAv 2 min"])
 
-      expect_audios([
-        {:canned,
-         {"113",
-          ["548", "21012", "587", "812", "5508", "505", "21012", "575", "621", "5502", "505"],
-          :audio}}
-      ])
+      expect_audios(
+        [
+          {:canned,
+           {"113",
+            ["548", "21012", "587", "812", "5508", "505", "21012", "575", "621", "5502", "505"],
+            :audio}}
+        ],
+        [
+          {"Upcoming departures: Route SL5, Nubian, 8 minutes. Route 14, Wakefield Ave, 2 minutes.",
+           nil}
+        ]
+      )
 
       state =
         Map.merge(@sign_state, %{
@@ -220,7 +238,7 @@ defmodule Signs.BusTest do
 
     test "static mode" do
       expect_messages(["custom", "message"])
-      expect_audios([{:ad_hoc, {"custom message", :audio}}])
+      expect_audios([{:ad_hoc, {"custom message", :audio}}], [{"custom message", nil}])
 
       state = Map.merge(@sign_state, %{id: "static_sign"})
 
@@ -245,31 +263,51 @@ defmodule Signs.BusTest do
         [{"14 WakfldAv 11 min", 6}, {"SL3 delays 4 more min", 6}]
       ])
 
-      expect_audios([
-        {:canned,
-         {"119",
-          [
-            "501",
-            "575",
-            "859",
-            "621",
-            "503",
-            "504",
-            "5502",
-            "505",
-            "21012",
-            "667",
-            "575",
-            "859",
-            "621",
-            "503",
-            "504",
-            "5511",
-            "505"
-          ], :audio}},
-        {:canned, {"135", ["5504"], :audio_visual}},
-        {:canned, {"152", ["37004"], :audio_visual}}
-      ])
+      expect_audios(
+        [
+          {:canned,
+           {"119",
+            [
+              "501",
+              "575",
+              "859",
+              "621",
+              "503",
+              "504",
+              "5502",
+              "505",
+              "21012",
+              "667",
+              "575",
+              "859",
+              "621",
+              "503",
+              "504",
+              "5511",
+              "505"
+            ], :audio}},
+          {:canned, {"135", ["5504"], :audio_visual}},
+          {:canned, {"152", ["37004"], :audio_visual}}
+        ],
+        [
+          {"The next route 14 bus to Wakefield Ave arrives in 2 minutes. The following route 14 bus to Wakefield Ave arrives in 11 minutes.",
+           nil},
+          {"The Chelsea Street bridge is raised. We expect this to last for at least 4 more minutes. SL3 buses may be delayed, detoured, or turned back.",
+           [
+             {"The Chelsea Street", "bridge is raised. We", 3},
+             {"expect this to last for", "at least 4 more minutes.", 3},
+             {"SL3 buses may be", "delayed, detoured, or", 3},
+             {"turned back.", "", 3}
+           ]},
+          {"El puente de Chelsea Street está levantado. Esperamos que esto dure al menos 4 minutos más. Los autobuses SL3 pueden sufrir retrasos, desvíos o dar marcha atrás.",
+           [
+             {"El puente de Chelsea", "Street está levantado.", 3},
+             {"Esperamos que esto dure", "al menos 4 minutos más.", 3},
+             {"Los autobuses SL3 pueden", "sufrir retrasos, desvíos", 3},
+             {"o dar marcha atrás.", "", 3}
+           ]}
+        ]
+      )
 
       state =
         Map.merge(@sign_state, %{
@@ -282,10 +320,28 @@ defmodule Signs.BusTest do
     end
 
     test "standalone bridge announcement" do
-      expect_audios([
-        {:canned, {"135", ["5504"], :audio_visual}},
-        {:canned, {"152", ["37004"], :audio_visual}}
-      ])
+      expect_audios(
+        [
+          {:canned, {"135", ["5504"], :audio_visual}},
+          {:canned, {"152", ["37004"], :audio_visual}}
+        ],
+        [
+          {"The Chelsea Street bridge is raised. We expect this to last for at least 4 more minutes. SL3 buses may be delayed, detoured, or turned back.",
+           [
+             {"The Chelsea Street", "bridge is raised. We", 3},
+             {"expect this to last for", "at least 4 more minutes.", 3},
+             {"SL3 buses may be", "delayed, detoured, or", 3},
+             {"turned back.", "", 3}
+           ]},
+          {"El puente de Chelsea Street está levantado. Esperamos que esto dure al menos 4 minutos más. Los autobuses SL3 pueden sufrir retrasos, desvíos o dar marcha atrás.",
+           [
+             {"El puente de Chelsea", "Street está levantado.", 3},
+             {"Esperamos que esto dure", "al menos 4 minutos más.", 3},
+             {"Los autobuses SL3 pueden", "sufrir retrasos, desvíos", 3},
+             {"o dar marcha atrás.", "", 3}
+           ]}
+        ]
+      )
 
       state =
         Map.merge(@sign_state, %{
@@ -303,7 +359,7 @@ defmodule Signs.BusTest do
 
     test "no service alert" do
       expect_messages(["No bus service", ""])
-      expect_audios([{:canned, {"103", ["878"], :audio}}])
+      expect_audios([{:canned, {"103", ["878"], :audio}}], [{"No bus service", nil}])
 
       state =
         Map.merge(@sign_state, %{
@@ -316,11 +372,17 @@ defmodule Signs.BusTest do
     test "route alert on multi-route sign" do
       expect_messages(["14 WakefldAv 2 min", "51 Resrvoir no svc"])
 
-      expect_audios([
-        {:canned,
-         {"112", ["548", "21012", "575", "621", "5502", "505", "21012", "687", "4076", "879"],
-          :audio}}
-      ])
+      expect_audios(
+        [
+          {:canned,
+           {"112", ["548", "21012", "575", "621", "5502", "505", "21012", "687", "4076", "879"],
+            :audio}}
+        ],
+        [
+          {"Upcoming departures: Route 14, Wakefield Ave, 2 minutes. Route 51, Reservoir Station, no service.",
+           nil}
+        ]
+      )
 
       state = %{
         @sign_state
@@ -336,7 +398,9 @@ defmodule Signs.BusTest do
     test "route alert on single-route sign" do
       expect_messages(["51 Resrvoir no svc", ""])
 
-      expect_audios([{:canned, {"106", ["880", "687", "877", "4076"], :audio}}])
+      expect_audios([{:canned, {"106", ["880", "687", "877", "4076"], :audio}}], [
+        {"There is no route 51 bus service to Reservoir Station.", nil}
+      ])
 
       state = %{
         @sign_state
@@ -354,9 +418,10 @@ defmodule Signs.BusTest do
     end)
   end
 
-  defp expect_audios(audios) do
-    expect(PaEss.Updater.Mock, :play_message, fn _, list, _, _ ->
+  defp expect_audios(audios, tts_audios) do
+    expect(PaEss.Updater.Mock, :play_message, fn _, list, tts_list, _ ->
       assert list == audios
+      assert tts_list == tts_audios
       :ok
     end)
   end