diff --git a/components/chat/ChatInput.vue b/components/chat/ChatInput.vue
index 4265a2eec..0bc904920 100644
--- a/components/chat/ChatInput.vue
+++ b/components/chat/ChatInput.vue
@@ -127,6 +127,17 @@ const fieldName = `chat-message-${Math.random().toString(36).slice(2, 10)}`;
                 ]"
                 @keydown.enter="onEnter"
               />
+              <span
+                v-if="showRemaining"
+                class="shrink-0 self-center font-mono text-[0.6rem] tabular-nums leading-none"
+                :class="
+                  remainingCharacters < 0
+                    ? 'text-destructive'
+                    : 'text-muted-foreground/70'
+                "
+              >
+                {{ remainingCharacters }}
+              </span>
               <Button
                 type="submit"
                 size="sm"
@@ -155,6 +166,10 @@ import * as z from "zod";
 import { useForm } from "vee-validate";
 import { toTypedSchema } from "~/utilities/vee-validate-zod";
 import { chatEnterAction } from "~/utilities/chatInputKeys";
+import { toastChatError } from "~/utilities/chatErrors";
+import { CHAT_MESSAGE_MAX_LENGTH } from "~/constants/chat";
+
+const REMAINING_HINT_AT = 200;
 
 export interface ChatInputChannel {
   value: string;
@@ -201,7 +216,7 @@ export default {
       form: useForm({
         validationSchema: toTypedSchema(
           z.object({
-            message: z.string().min(1),
+            message: z.string().trim().min(1).max(CHAT_MESSAGE_MAX_LENGTH),
           }),
         ),
       }),
@@ -211,6 +226,14 @@ export default {
     hasChannels() {
       return this.channels.length > 1;
     },
+    remainingCharacters(): number {
+      const message = this.form.values.message?.trim() ?? "";
+
+      return CHAT_MESSAGE_MAX_LENGTH - message.length;
+    },
+    showRemaining(): boolean {
+      return this.remainingCharacters <= REMAINING_HINT_AT;
+    },
     activeChannelValue() {
       return this.destination ?? this.channels[0]?.value;
     },
@@ -318,6 +341,10 @@ export default {
       if (!message) {
         return;
       }
+      if (message.length > CHAT_MESSAGE_MAX_LENGTH) {
+        toastChatError({ code: "too_long", max: CHAT_MESSAGE_MAX_LENGTH });
+        return;
+      }
       this.$emit(
         "sendMessage",
         message,
diff --git a/components/chat/ChatMessage.vue b/components/chat/ChatMessage.vue
index db20f6315..e8406b976 100644
--- a/components/chat/ChatMessage.vue
+++ b/components/chat/ChatMessage.vue
@@ -173,7 +173,10 @@ export default {
       if (this.previousMessage.__channel !== this.message.__channel) {
         return false;
       }
-      return this.message.from.steam_id === this.previousMessage.from.steam_id;
+      return (
+        String(this.message.from?.steam_id) ===
+        String(this.previousMessage.from?.steam_id)
+      );
     },
     isCloseTogether() {
       if (!this.isSameSender || !this.previousMessage) {
diff --git a/constants/chat.ts b/constants/chat.ts
new file mode 100644
index 000000000..cb13c34e3
--- /dev/null
+++ b/constants/chat.ts
@@ -0,0 +1,3 @@
+// Must match the api's ChatService.MAX_MESSAGE_LENGTH. Both sides count
+// .length (UTF-16 code units) of the trimmed text.
+export const CHAT_MESSAGE_MAX_LENGTH = 2000;
diff --git a/i18n/locales/ar_SA.json b/i18n/locales/ar_SA.json
index 5549483a9..a2fb09b2f 100644
--- a/i18n/locales/ar_SA.json
+++ b/i18n/locales/ar_SA.json
@@ -8465,6 +8465,8 @@
     "send_other_hint": "اضغط Ctrl+Enter للإرسال إلى {channel}",
     "everyone_hint": "كلا الفريقين — ويظهر أيضًا في دردشة اللعبة",
     "team_hint": "تشكيلتك فقط — ولا يظهر في دردشة اللعبة",
+    "message_too_long": "الحد الأقصى لطول الرسالة هو {max} حرف.",
+    "send_failed": "تعذّر إرسال رسالتك",
     "direct": {
       "message": "رسالة",
       "empty": "لا رسائل بعد. ألقِ التحية."
diff --git a/i18n/locales/da_DK.json b/i18n/locales/da_DK.json
index 5478aae68..371b0df19 100644
--- a/i18n/locales/da_DK.json
+++ b/i18n/locales/da_DK.json
@@ -8465,6 +8465,8 @@
     "send_other_hint": "Ctrl+Enter for at sende til {channel}",
     "everyone_hint": "Begge hold — vises også i spillets chat",
     "team_hint": "Kun din opstilling — vises ikke i spillets chat",
+    "message_too_long": "Beskeder kan højst være på {max} tegn.",
+    "send_failed": "Din besked kunne ikke sendes",
     "direct": {
       "message": "Besked",
       "empty": "Ingen beskeder endnu. Sig hej."
diff --git a/i18n/locales/de_DE.json b/i18n/locales/de_DE.json
index a3296c59c..dd4dd9589 100644
--- a/i18n/locales/de_DE.json
+++ b/i18n/locales/de_DE.json
@@ -8465,6 +8465,8 @@
     "send_other_hint": "Strg+Enter, um an {channel} zu senden",
     "everyone_hint": "Beide Teams — wird auch im Spielchat angezeigt",
     "team_hint": "Nur dein Lineup — wird nicht im Spielchat angezeigt",
+    "message_too_long": "Nachrichten dürfen höchstens {max} Zeichen lang sein.",
+    "send_failed": "Deine Nachricht konnte nicht gesendet werden",
     "direct": {
       "message": "Nachricht",
       "empty": "Noch keine Nachrichten. Sag Hallo."
diff --git a/i18n/locales/en.json b/i18n/locales/en.json
index f58be839a..31bbbfee2 100644
--- a/i18n/locales/en.json
+++ b/i18n/locales/en.json
@@ -8465,6 +8465,8 @@
     "send_other_hint": "Ctrl+Enter to send to {channel}",
     "everyone_hint": "Both teams — also shown in game chat",
     "team_hint": "Your lineup only — not shown in game chat",
+    "message_too_long": "Messages can be up to {max} characters.",
+    "send_failed": "Failed to send message",
     "direct": {
       "message": "Message",
       "empty": "No messages yet. Say hello."
diff --git a/i18n/locales/es_ES.json b/i18n/locales/es_ES.json
index 5a15ba395..09eefbd91 100644
--- a/i18n/locales/es_ES.json
+++ b/i18n/locales/es_ES.json
@@ -8465,6 +8465,8 @@
     "send_other_hint": "Ctrl+Intro para enviar a {channel}",
     "everyone_hint": "Ambos equipos: también se muestra en el chat del juego",
     "team_hint": "Solo tu alineación: no se muestra en el chat del juego",
+    "message_too_long": "Los mensajes pueden tener un máximo de {max} caracteres.",
+    "send_failed": "No se ha podido enviar tu mensaje",
     "direct": {
       "message": "Mensaje",
       "empty": "Aún no hay mensajes. Saluda."
diff --git a/i18n/locales/fr_FR.json b/i18n/locales/fr_FR.json
index ac412db74..75d56f574 100644
--- a/i18n/locales/fr_FR.json
+++ b/i18n/locales/fr_FR.json
@@ -8465,6 +8465,8 @@
     "send_other_hint": "Ctrl+Entrée pour envoyer à {channel}",
     "everyone_hint": "Les deux équipes — également affiché dans le chat du jeu",
     "team_hint": "Votre composition uniquement — non affiché dans le chat du jeu",
+    "message_too_long": "Les messages peuvent contenir jusqu'à {max} caractères.",
+    "send_failed": "Votre message n'a pas pu être envoyé",
     "direct": {
       "message": "Message",
       "empty": "Aucun message pour l'instant. Dites bonjour."
diff --git a/i18n/locales/it_IT.json b/i18n/locales/it_IT.json
index bece59c51..fd8fea450 100644
--- a/i18n/locales/it_IT.json
+++ b/i18n/locales/it_IT.json
@@ -8465,6 +8465,8 @@
     "send_other_hint": "Ctrl+Invio per inviare a {channel}",
     "everyone_hint": "Entrambe le squadre — mostrato anche nella chat di gioco",
     "team_hint": "Solo la tua formazione — non mostrato nella chat di gioco",
+    "message_too_long": "I messaggi possono contenere al massimo {max} caratteri.",
+    "send_failed": "Non è stato possibile inviare il tuo messaggio",
     "direct": {
       "message": "Messaggio",
       "empty": "Ancora nessun messaggio. Fatti sentire."
diff --git a/i18n/locales/ja_JP.json b/i18n/locales/ja_JP.json
index 8411f6275..53046566a 100644
--- a/i18n/locales/ja_JP.json
+++ b/i18n/locales/ja_JP.json
@@ -8465,6 +8465,8 @@
     "send_other_hint": "Ctrl+Enterで {channel} に送信",
     "everyone_hint": "両チーム — ゲーム内チャットにも表示されます",
     "team_hint": "自分のラインナップのみ — ゲーム内チャットには表示されません",
+    "message_too_long": "メッセージは最大{max}文字までです。",
+    "send_failed": "メッセージを送信できませんでした",
     "direct": {
       "message": "メッセージ",
       "empty": "まだメッセージはありません。あいさつしてみましょう。"
diff --git a/i18n/locales/ko_KR.json b/i18n/locales/ko_KR.json
index dfaa86cbb..737ae8488 100644
--- a/i18n/locales/ko_KR.json
+++ b/i18n/locales/ko_KR.json
@@ -8465,6 +8465,8 @@
     "send_other_hint": "Ctrl+Enter로 {channel}에 보내기",
     "everyone_hint": "양 팀 — 게임 내 채팅에도 표시됩니다",
     "team_hint": "내 라인업만 — 게임 내 채팅에는 표시되지 않습니다",
+    "message_too_long": "메시지는 최대 {max}자까지 입력할 수 있습니다.",
+    "send_failed": "메시지를 보내지 못했습니다",
     "direct": {
       "message": "메시지",
       "empty": "아직 메시지가 없습니다. 인사를 건네보세요."
diff --git a/i18n/locales/pl_PL.json b/i18n/locales/pl_PL.json
index d5cc20619..021c96bb5 100644
--- a/i18n/locales/pl_PL.json
+++ b/i18n/locales/pl_PL.json
@@ -8465,6 +8465,8 @@
     "send_other_hint": "Ctrl+Enter, aby wysłać do {channel}",
     "everyone_hint": "Obie drużyny — pokazywane także na czacie w grze",
     "team_hint": "Tylko twój skład — nie jest pokazywane na czacie w grze",
+    "message_too_long": "Wiadomość może mieć maksymalnie {max} znaków.",
+    "send_failed": "Nie udało się wysłać wiadomości",
     "direct": {
       "message": "Wiadomość",
       "empty": "Brak wiadomości. Przywitaj się."
diff --git a/i18n/locales/pt_BR.json b/i18n/locales/pt_BR.json
index 44eb57166..15d2ec955 100644
--- a/i18n/locales/pt_BR.json
+++ b/i18n/locales/pt_BR.json
@@ -8465,6 +8465,8 @@
     "send_other_hint": "Ctrl+Enter para enviar para {channel}",
     "everyone_hint": "Ambas as equipes — também mostrado no chat do jogo",
     "team_hint": "Apenas sua equipe — não mostrado no chat do jogo",
+    "message_too_long": "As mensagens podem ter no máximo {max} caracteres.",
+    "send_failed": "Não foi possível enviar sua mensagem",
     "direct": {
       "message": "Mensagem",
       "empty": "Nenhuma mensagem ainda. Diga Olá."
diff --git a/i18n/locales/ru_RU.json b/i18n/locales/ru_RU.json
index a5b1ba11a..577298aa6 100644
--- a/i18n/locales/ru_RU.json
+++ b/i18n/locales/ru_RU.json
@@ -8465,6 +8465,8 @@
     "send_other_hint": "Ctrl+Enter, чтобы отправить в {channel}",
     "everyone_hint": "Обе команды — также отображается в игровом чате",
     "team_hint": "Только ваш состав — в игровом чате не отображается",
+    "message_too_long": "Сообщение может содержать не более {max} символов.",
+    "send_failed": "Не удалось отправить сообщение",
     "direct": {
       "message": "Сообщение",
       "empty": "Сообщений пока нет. Поздоровайтесь."
diff --git a/i18n/locales/sv_SE.json b/i18n/locales/sv_SE.json
index 1ec6bf0c0..0bf7de94f 100644
--- a/i18n/locales/sv_SE.json
+++ b/i18n/locales/sv_SE.json
@@ -8465,6 +8465,8 @@
     "send_other_hint": "Ctrl+Enter för att skicka till {channel}",
     "everyone_hint": "Båda lagen — visas även i spelets chatt",
     "team_hint": "Bara din laguppställning — visas inte i spelets chatt",
+    "message_too_long": "Meddelanden får vara högst {max} tecken långa.",
+    "send_failed": "Ditt meddelande kunde inte skickas",
     "direct": {
       "message": "Meddelande",
       "empty": "Inga meddelanden än. Säg hej."
diff --git a/i18n/locales/tr_TR.json b/i18n/locales/tr_TR.json
index d76958cbe..f49c14d41 100644
--- a/i18n/locales/tr_TR.json
+++ b/i18n/locales/tr_TR.json
@@ -8465,6 +8465,8 @@
     "send_other_hint": "{channel} kanalına göndermek için Ctrl+Enter",
     "everyone_hint": "Her iki takım — oyun içi sohbette de görünür",
     "team_hint": "Yalnızca kendi kadron — oyun içi sohbette görünmez",
+    "message_too_long": "Mesajlar en fazla {max} karakter olabilir.",
+    "send_failed": "Mesajın gönderilemedi",
     "direct": {
       "message": "Mesaj",
       "empty": "Henüz mesaj yok. Merhaba de."
diff --git a/i18n/locales/uk_UA.json b/i18n/locales/uk_UA.json
index 58fb3553f..dcc07cb7d 100644
--- a/i18n/locales/uk_UA.json
+++ b/i18n/locales/uk_UA.json
@@ -8465,6 +8465,8 @@
     "send_other_hint": "Ctrl+Enter, щоб надіслати в {channel}",
     "everyone_hint": "Обидві команди — також показується в ігровому чаті",
     "team_hint": "Лише ваш склад — в ігровому чаті не показується",
+    "message_too_long": "Повідомлення може містити не більше {max} символів.",
+    "send_failed": "Не вдалося надіслати повідомлення",
     "direct": {
       "message": "Повідомлення",
       "empty": "Повідомлень поки немає. Привітайтеся."
diff --git a/i18n/locales/zh_Hans.json b/i18n/locales/zh_Hans.json
index 231e6aedf..e800cb9b8 100644
--- a/i18n/locales/zh_Hans.json
+++ b/i18n/locales/zh_Hans.json
@@ -8465,6 +8465,8 @@
     "send_other_hint": "按 Ctrl+Enter 发送到 {channel}",
     "everyone_hint": "两支战队 — 也会显示在游戏内聊天",
     "team_hint": "仅限你的阵容 — 不会显示在游戏内聊天",
+    "message_too_long": "消息最多 {max} 个字符。",
+    "send_failed": "消息发送失败",
     "direct": {
       "message": "消息",
       "empty": "还没有消息，先打个招呼吧。"
diff --git a/i18n/locales/zh_Hant.json b/i18n/locales/zh_Hant.json
index 024219dac..63248280e 100644
--- a/i18n/locales/zh_Hant.json
+++ b/i18n/locales/zh_Hant.json
@@ -8465,6 +8465,8 @@
     "send_other_hint": "按 Ctrl+Enter 傳送到 {channel}",
     "everyone_hint": "兩支隊伍 — 也會顯示在遊戲內聊天",
     "team_hint": "僅限你的名單 — 不會顯示在遊戲內聊天",
+    "message_too_long": "訊息最多 {max} 個字元。",
+    "send_failed": "訊息傳送失敗",
     "direct": {
       "message": "訊息",
       "empty": "還沒有訊息，先打個招呼吧。"
diff --git a/tests/components/ChatInput.spec.ts b/tests/components/ChatInput.spec.ts
new file mode 100644
index 000000000..3bd620137
--- /dev/null
+++ b/tests/components/ChatInput.spec.ts
@@ -0,0 +1,120 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import { flushPromises } from "@vue/test-utils";
+import { mountSuspended } from "@nuxt/test-utils/runtime";
+import ChatInput from "~/components/chat/ChatInput.vue";
+import { CHAT_MESSAGE_MAX_LENGTH } from "~/constants/chat";
+
+const { toast } = vi.hoisted(() => ({ toast: vi.fn() }));
+
+vi.mock("@/components/ui/toast", async (importOriginal) => ({
+  ...(await importOriginal<typeof import("@/components/ui/toast")>()),
+  toast,
+}));
+
+type Wrapper = Awaited<ReturnType<typeof mountSuspended>>;
+
+async function type(wrapper: Wrapper, text: string) {
+  await wrapper.get("textarea").setValue(text);
+  await flushPromises();
+}
+
+async function submit(wrapper: Wrapper) {
+  await wrapper.get("form").trigger("submit");
+  await flushPromises();
+}
+
+const textarea = (wrapper: Wrapper) =>
+  wrapper.get("textarea").element as HTMLTextAreaElement;
+
+const remaining = (wrapper: Wrapper) => wrapper.find(".tabular-nums");
+
+describe("ChatInput", () => {
+  beforeEach(() => {
+    toast.mockClear();
+  });
+
+  it("sends the trimmed text and clears the box", async () => {
+    const wrapper = await mountSuspended(ChatInput);
+
+    await type(wrapper, "  gg wp  ");
+    await submit(wrapper);
+
+    expect(wrapper.emitted("sendMessage")).toEqual([["gg wp", undefined]]);
+    expect(textarea(wrapper).value).toBe("");
+    expect(toast).not.toHaveBeenCalled();
+  });
+
+  it("sends a message of exactly the limit", async () => {
+    const wrapper = await mountSuspended(ChatInput);
+    const message = "a".repeat(CHAT_MESSAGE_MAX_LENGTH);
+
+    await type(wrapper, message);
+    await submit(wrapper);
+
+    expect(wrapper.emitted("sendMessage")).toEqual([[message, undefined]]);
+    expect(toast).not.toHaveBeenCalled();
+  });
+
+  it("measures the limit after trimming, like the api", async () => {
+    const wrapper = await mountSuspended(ChatInput);
+    const message = "a".repeat(CHAT_MESSAGE_MAX_LENGTH);
+
+    await type(wrapper, `   ${message}\n `);
+    await submit(wrapper);
+
+    expect(wrapper.emitted("sendMessage")).toEqual([[message, undefined]]);
+  });
+
+  it("refuses an over-length message and keeps the text", async () => {
+    const wrapper = await mountSuspended(ChatInput);
+    const message = "a".repeat(CHAT_MESSAGE_MAX_LENGTH + 1);
+
+    await type(wrapper, message);
+    await submit(wrapper);
+
+    expect(wrapper.emitted("sendMessage")).toBeUndefined();
+    expect(textarea(wrapper).value).toBe(message);
+    expect(toast).toHaveBeenCalledTimes(1);
+    expect(toast).toHaveBeenCalledWith({
+      title: "Failed to send message",
+      description: "Messages can be up to 2000 characters.",
+      variant: "destructive",
+    });
+  });
+
+  it("refuses an over-length message sent with enter", async () => {
+    const wrapper = await mountSuspended(ChatInput);
+    const message = "a".repeat(CHAT_MESSAGE_MAX_LENGTH + 1);
+
+    await type(wrapper, message);
+    await wrapper.get("textarea").trigger("keydown", { key: "Enter" });
+    await flushPromises();
+
+    expect(wrapper.emitted("sendMessage")).toBeUndefined();
+    expect(textarea(wrapper).value).toBe(message);
+    expect(toast).toHaveBeenCalledTimes(1);
+  });
+
+  it("counts down only near the limit", async () => {
+    const wrapper = await mountSuspended(ChatInput);
+
+    await type(wrapper, "a".repeat(CHAT_MESSAGE_MAX_LENGTH - 201));
+    expect(remaining(wrapper).exists()).toBe(false);
+
+    await type(wrapper, "a".repeat(CHAT_MESSAGE_MAX_LENGTH - 200));
+    expect(remaining(wrapper).text()).toBe("200");
+    expect(remaining(wrapper).classes()).not.toContain("text-destructive");
+
+    await type(wrapper, "a".repeat(CHAT_MESSAGE_MAX_LENGTH + 5));
+    expect(remaining(wrapper).text()).toBe("-5");
+    expect(remaining(wrapper).classes()).toContain("text-destructive");
+  });
+
+  it("counts what will be sent, not surrounding whitespace", async () => {
+    const wrapper = await mountSuspended(ChatInput);
+
+    await type(wrapper, ` ${"a".repeat(CHAT_MESSAGE_MAX_LENGTH - 200)}\n  `);
+
+    expect(remaining(wrapper).text()).toBe("200");
+  });
+});
diff --git a/tests/components/ChatMessage.spec.ts b/tests/components/ChatMessage.spec.ts
new file mode 100644
index 000000000..bb348a650
--- /dev/null
+++ b/tests/components/ChatMessage.spec.ts
@@ -0,0 +1,54 @@
+import { describe, expect, it } from "vitest";
+import { mountSuspended } from "@nuxt/test-utils/runtime";
+import ChatMessage from "~/components/chat/ChatMessage.vue";
+
+const line = (steamId: string, minute: number, message: string) => ({
+  id: message,
+  message,
+  source: "web",
+  timestamp: new Date(Date.UTC(2026, 8, 28, 12, minute)).toISOString(),
+  from: { steam_id: steamId, name: `Player ${steamId}` },
+});
+
+describe("ChatMessage grouping", () => {
+  it("folds a second line from the same sender under the first", async () => {
+    const wrapper = await mountSuspended(ChatMessage, {
+      props: {
+        previousMessage: line("76561198000000001", 0, "first"),
+        message: line("76561198000000001", 1, "second"),
+      },
+    });
+
+    expect(wrapper.find("h4").exists()).toBe(false);
+    expect(wrapper.text()).toContain("second");
+  });
+
+  it("folds under an older line that stored the sender id as a number", async () => {
+    const wrapper = await mountSuspended(ChatMessage, {
+      props: {
+        previousMessage: {
+          ...line("76561198000000000", 0, "first"),
+          from: {
+            steam_id: 76561198000000000,
+            name: "Player 76561198000000000",
+          },
+        },
+        message: line("76561198000000000", 1, "second"),
+      },
+    });
+
+    expect(wrapper.find("h4").exists()).toBe(false);
+    expect(wrapper.text()).toContain("second");
+  });
+
+  it("names the sender when someone else spoke last", async () => {
+    const wrapper = await mountSuspended(ChatMessage, {
+      props: {
+        previousMessage: line("76561198000000002", 0, "first"),
+        message: line("76561198000000001", 1, "second"),
+      },
+    });
+
+    expect(wrapper.get("h4").text()).toBe("Player 76561198000000001");
+  });
+});
diff --git a/tests/utilities/chatErrors.spec.ts b/tests/utilities/chatErrors.spec.ts
new file mode 100644
index 000000000..7fa82ed25
--- /dev/null
+++ b/tests/utilities/chatErrors.spec.ts
@@ -0,0 +1,36 @@
+import { describe, expect, it } from "vitest";
+import { chatErrorDescription } from "~/utilities/chatErrors";
+import { CHAT_MESSAGE_MAX_LENGTH } from "~/constants/chat";
+
+const t = (key: string, params?: Record<string, unknown>) =>
+  params ? `${key} ${JSON.stringify(params)}` : key;
+
+describe("chatErrorDescription", () => {
+  it("says how long a message can be", () => {
+    expect(chatErrorDescription({ code: "too_long", max: 1500 }, t)).toBe(
+      'chat.message_too_long {"max":1500}',
+    );
+  });
+
+  it("falls back to the local limit when the api sends no max", () => {
+    expect(chatErrorDescription({ code: "too_long" }, t)).toBe(
+      `chat.message_too_long {"max":${CHAT_MESSAGE_MAX_LENGTH}}`,
+    );
+  });
+
+  it("adds nothing to the failed-send title for a refused send", () => {
+    // not_allowed can be a send queued offline that beat its lobby rejoin
+    expect(chatErrorDescription({ code: "not_allowed" }, t)).toBeUndefined();
+  });
+
+  it.each(["invalid", "some_future_code", ""])(
+    "treats %j as a plain failed send",
+    (code) => {
+      expect(chatErrorDescription({ code }, t)).toBeUndefined();
+    },
+  );
+
+  it("survives a payload with no code", () => {
+    expect(chatErrorDescription(undefined as any, t)).toBeUndefined();
+  });
+});
diff --git a/tests/web-sockets/SocketChatError.spec.ts b/tests/web-sockets/SocketChatError.spec.ts
new file mode 100644
index 000000000..4afc2b3f2
--- /dev/null
+++ b/tests/web-sockets/SocketChatError.spec.ts
@@ -0,0 +1,38 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import socket from "~/web-sockets/Socket";
+
+const { toast } = vi.hoisted(() => ({ toast: vi.fn() }));
+
+vi.mock("@/components/ui/toast", async (importOriginal) => ({
+  ...(await importOriginal<typeof import("@/components/ui/toast")>()),
+  toast,
+}));
+
+describe("Socket chat:error", () => {
+  beforeEach(() => {
+    toast.mockClear();
+  });
+
+  it("toasts the limit for a message that is too long", () => {
+    socket.emit("chat:error", { code: "too_long", max: 2000, requestId: "r" });
+
+    expect(toast).toHaveBeenCalledWith({
+      title: "Failed to send message",
+      description: "Messages can be up to 2000 characters.",
+      variant: "destructive",
+    });
+  });
+
+  it.each(["not_allowed", "invalid", "gagged"])(
+    "toasts a failed send for %s",
+    (code) => {
+      socket.emit("chat:error", { code });
+
+      expect(toast).toHaveBeenCalledWith({
+        title: "Failed to send message",
+        description: undefined,
+        variant: "destructive",
+      });
+    },
+  );
+});
diff --git a/utilities/chatErrors.ts b/utilities/chatErrors.ts
new file mode 100644
index 000000000..a606e3d55
--- /dev/null
+++ b/utilities/chatErrors.ts
@@ -0,0 +1,38 @@
+import { toast } from "@/components/ui/toast";
+import { CHAT_MESSAGE_MAX_LENGTH } from "~/constants/chat";
+
+export interface ChatError {
+  code: string;
+  max?: number;
+  requestId?: string;
+}
+
+type Translate = (key: string, params?: Record<string, unknown>) => string;
+
+export function chatErrorDescription(
+  error: ChatError,
+  t: Translate,
+): string | undefined {
+  switch (error?.code) {
+    case "too_long":
+      return t("chat.message_too_long", {
+        max: error.max ?? CHAT_MESSAGE_MAX_LENGTH,
+      });
+    // Also sent when a send queued while offline reaches the server before the
+    // lobby rejoin does, so it must not tell the user they are barred.
+    case "not_allowed":
+    default:
+      return undefined;
+  }
+}
+
+export function toastChatError(error: ChatError) {
+  const { $i18n } = useNuxtApp();
+  const t: Translate = (key, params) => $i18n.t(key, params ?? {});
+
+  toast({
+    title: t("chat.send_failed"),
+    description: chatErrorDescription(error, t),
+    variant: "destructive",
+  });
+}
diff --git a/web-sockets/Socket.ts b/web-sockets/Socket.ts
index 29ba89efc..c171ee413 100644
--- a/web-sockets/Socket.ts
+++ b/web-sockets/Socket.ts
@@ -3,11 +3,13 @@ import { shallowRef, type ShallowRef } from "vue";
 import type { e_match_types_enum } from "~/generated/zeus";
 import { toast } from "@/components/ui/toast";
 import { useChatReadState } from "~/composables/useChatReadState";
+import { toastChatError } from "~/utilities/chatErrors";
 
 export interface LobbyMessage {
   id?: string;
   message: string;
   timestamp: string;
+  source?: "web" | "game";
   from?: {
     role?: string;
     name?: string;
@@ -671,6 +673,8 @@ socket.listen(
   },
 );
 
+socket.listen("chat:error", toastChatError);
+
 socket.listen("matchmaking:region-stats", (data) => {
   useMatchmakingStore().regionStats = data;
 });