diff --git a/bin/cli/commands/cost.mjs b/bin/cli/commands/cost.mjs
new file mode 100644
index 0000000000..5745c2761d
--- /dev/null
+++ b/bin/cli/commands/cost.mjs
@@ -0,0 +1,144 @@
+import { apiFetch } from "../api.mjs";
+import { emit } from "../output.mjs";
+import { t } from "../i18n.mjs";
+
+const costSchema = [
+  { key: "group", header: "Group", width: 30 },
+  { key: "requests", header: "Reqs", formatter: (v) => (v != null ? v.toLocaleString() : "0") },
+  { key: "tokensIn", header: "Tokens In", formatter: fmtTokens },
+  { key: "tokensOut", header: "Tokens Out", formatter: fmtTokens },
+  { key: "costUsd", header: "Cost (USD)", formatter: (v) => (v ? `$${v.toFixed(4)}` : "$0.0000") },
+  {
+    key: "costPct",
+    header: "% of Total",
+    formatter: (v) => (v != null ? `${v.toFixed(1)}%` : "-"),
+  },
+];
+
+function fmtTokens(v) {
+  if (!v) return "0";
+  if (v > 1e6) return `${(v / 1e6).toFixed(1)}M`;
+  if (v > 1e3) return `${(v / 1e3).toFixed(1)}K`;
+  return String(v);
+}
+
+export function registerCost(program) {
+  program
+    .command("cost")
+    .description(t("cost.description"))
+    .option("--period <range>", t("cost.period"), "30d")
+    .option("--since <date>", t("cost.since"))
+    .option("--until <date>", t("cost.until"))
+    .option("--group-by <field>", t("cost.group_by"), "provider")
+    .option("--api-key <key>", t("cost.api_key_filter"))
+    .option("--limit <n>", t("cost.limit"), parseInt, 100)
+    .action(runCostCommand);
+}
+
+export async function runCostCommand(opts, cmd) {
+  const globalOpts = cmd.optsWithGlobals();
+  const params = buildParams(opts);
+
+  const res = await apiFetch(`/api/usage/analytics?${params}`, {
+    timeout: globalOpts.timeout,
+    acceptNotOk: true,
+  });
+
+  if (!res.ok) {
+    if (res.status === 401 || res.status === 403) {
+      process.stderr.write(t("common.authRequired") + "\n");
+    } else if (res.status >= 500) {
+      process.stderr.write(t("common.serverOffline") + "\n");
+    } else {
+      process.stderr.write(t("common.error", { message: `HTTP ${res.status}` }) + "\n");
+    }
+    process.exit(res.exitCode ?? 1);
+  }
+
+  const data = await res.json();
+  const rows = aggregateByGroup(data, opts.groupBy ?? "provider", opts.limit ?? 100);
+
+  emit(rows, globalOpts, costSchema);
+
+  if (!globalOpts.quiet && globalOpts.output !== "json" && globalOpts.output !== "jsonl") {
+    const total = rows.reduce((s, r) => s + (r.costUsd ?? 0), 0);
+    process.stderr.write(
+      `\nTotal: $${total.toFixed(4)} across ${rows.length} ${opts.groupBy ?? "provider"}(s)\n`
+    );
+  }
+}
+
+function buildParams(opts) {
+  const p = new URLSearchParams();
+  if (opts.since || opts.until) {
+    if (opts.since) p.set("startDate", opts.since);
+    if (opts.until) p.set("endDate", opts.until);
+  } else {
+    p.set("range", opts.period ?? "30d");
+  }
+  if (opts.apiKey) p.set("apiKeyIds", opts.apiKey);
+  return p.toString();
+}
+
+function aggregateByGroup(data, groupBy, limit) {
+  const source = pickSource(data, groupBy);
+  if (!Array.isArray(source)) return [];
+
+  const totalCost = source.reduce((s, r) => s + toNum(r.totalCost ?? r.cost ?? r.costUsd), 0);
+
+  const rows = source.map((r) => {
+    const costUsd = toNum(r.totalCost ?? r.cost ?? r.costUsd);
+    return {
+      group: groupLabel(r, groupBy),
+      requests: toNum(r.totalRequests ?? r.requests ?? r.count),
+      tokensIn: toNum(r.totalTokensIn ?? r.tokensIn ?? r.promptTokens),
+      tokensOut: toNum(r.totalTokensOut ?? r.tokensOut ?? r.completionTokens),
+      costUsd,
+      costPct: totalCost > 0 ? (costUsd / totalCost) * 100 : 0,
+    };
+  });
+
+  rows.sort((a, b) => b.costUsd - a.costUsd);
+  return rows.slice(0, limit);
+}
+
+function pickSource(data, groupBy) {
+  switch (groupBy) {
+    case "model":
+      return data.byModel ?? data.models ?? [];
+    case "combo":
+      return data.byCombo ?? data.combos ?? [];
+    case "api-key":
+    case "apiKey":
+      return data.byApiKey ?? data.apiKeys ?? [];
+    case "day":
+      return data.byDay ?? data.daily ?? data.trend ?? [];
+    default:
+      return data.byProvider ?? data.providers ?? [];
+  }
+}
+
+function groupLabel(row, groupBy) {
+  switch (groupBy) {
+    case "model":
+      return row.model ?? row.modelId ?? String(row.group ?? "");
+    case "combo":
+      return row.comboName ?? row.combo ?? row.name ?? String(row.group ?? "");
+    case "api-key":
+    case "apiKey":
+      return row.keyName ?? row.apiKey ?? row.label ?? String(row.group ?? "");
+    case "day":
+      return row.date ?? row.day ?? String(row.group ?? "");
+    default:
+      return row.provider ?? row.providerId ?? String(row.group ?? "");
+  }
+}
+
+function toNum(v) {
+  if (typeof v === "number" && Number.isFinite(v)) return v;
+  if (typeof v === "string") {
+    const n = Number(v);
+    return Number.isFinite(n) ? n : 0;
+  }
+  return 0;
+}
diff --git a/bin/cli/commands/registry.mjs b/bin/cli/commands/registry.mjs
index 4fd5a762fc..d8772a856b 100644
--- a/bin/cli/commands/registry.mjs
+++ b/bin/cli/commands/registry.mjs
@@ -1,6 +1,7 @@
 import { registerChat } from "./chat.mjs";
 import { registerStream } from "./stream.mjs";
 import { registerSimulate } from "./simulate.mjs";
+import { registerCost } from "./cost.mjs";
 import { registerServe } from "./serve.mjs";
 import { registerStop } from "./stop.mjs";
 import { registerRestart } from "./restart.mjs";
@@ -31,6 +32,7 @@ export function registerCommands(program) {
   registerChat(program);
   registerStream(program);
   registerSimulate(program);
+  registerCost(program);
   registerServe(program);
   registerStop(program);
   registerRestart(program);
diff --git a/bin/cli/locales/en.json b/bin/cli/locales/en.json
index fa1a728d2b..9b2d38b33d 100644
--- a/bin/cli/locales/en.json
+++ b/bin/cli/locales/en.json
@@ -70,6 +70,15 @@
       "empty_prompt": "Error: prompt is required (positional arg, --file, or --stdin)"
     }
   },
+  "cost": {
+    "description": "Show cost report with breakdown by provider, model, combo, or API key",
+    "period": "Time range: 1d|7d|30d|90d|ytd|all (default: 30d)",
+    "since": "Start date (ISO format, e.g. 2026-01-01) — overrides --period",
+    "until": "End date (ISO format)",
+    "group_by": "Group results by: provider|model|api-key|combo|day (default: provider)",
+    "api_key_filter": "Filter by a specific API key",
+    "limit": "Maximum number of rows to show (default: 100)"
+  },
   "simulate": {
     "description": "Dry-run routing simulation — show which providers would be selected without calling upstream",
     "file": "Load full request body from JSON file",
diff --git a/bin/cli/locales/pt-BR.json b/bin/cli/locales/pt-BR.json
index 799a399f8b..0bfd8cf6df 100644
--- a/bin/cli/locales/pt-BR.json
+++ b/bin/cli/locales/pt-BR.json
@@ -70,6 +70,15 @@
       "empty_prompt": "Erro: prompt obrigatório (argumento posicional, --file ou --stdin)"
     }
   },
+  "cost": {
+    "description": "Exibir relatório de custos com breakdown por provedor, modelo, combo ou chave de API",
+    "period": "Período: 1d|7d|30d|90d|ytd|all (padrão: 30d)",
+    "since": "Data de início (formato ISO, ex: 2026-01-01) — substitui --period",
+    "until": "Data de fim (formato ISO)",
+    "group_by": "Agrupar por: provider|model|api-key|combo|day (padrão: provider)",
+    "api_key_filter": "Filtrar por uma chave de API específica",
+    "limit": "Número máximo de linhas (padrão: 100)"
+  },
   "simulate": {
     "description": "Simulação de routing em dry-run — mostra quais provedores seriam selecionados sem chamar o upstream",
     "file": "Carregar body completo da requisição de arquivo JSON",
diff --git a/tests/unit/cli-cost.test.ts b/tests/unit/cli-cost.test.ts
new file mode 100644
index 0000000000..2cda136918
--- /dev/null
+++ b/tests/unit/cli-cost.test.ts
@@ -0,0 +1,215 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+
+const ANALYTICS_RESPONSE = {
+  byProvider: [
+    {
+      provider: "openai",
+      totalRequests: 150,
+      totalTokensIn: 50000,
+      totalTokensOut: 20000,
+      totalCost: 0.42,
+    },
+    {
+      provider: "anthropic",
+      totalRequests: 80,
+      totalTokensIn: 30000,
+      totalTokensOut: 12000,
+      totalCost: 0.18,
+    },
+  ],
+  byModel: [
+    {
+      model: "gpt-4o",
+      totalRequests: 100,
+      totalTokensIn: 40000,
+      totalTokensOut: 16000,
+      totalCost: 0.35,
+    },
+    {
+      model: "claude-3-5-sonnet",
+      totalRequests: 80,
+      totalTokensIn: 30000,
+      totalTokensOut: 12000,
+      totalCost: 0.18,
+    },
+  ],
+  byDay: [
+    {
+      date: "2026-05-14",
+      totalRequests: 50,
+      totalTokensIn: 20000,
+      totalTokensOut: 8000,
+      totalCost: 0.15,
+    },
+    {
+      date: "2026-05-15",
+      totalRequests: 60,
+      totalTokensIn: 22000,
+      totalTokensOut: 9000,
+      totalCost: 0.17,
+    },
+  ],
+};
+
+function makeResp(data: unknown, status = 200) {
+  const obj = {
+    ok: status < 400,
+    status,
+    exitCode: status >= 200 && status < 300 ? 0 : 1,
+    json: () => Promise.resolve(data),
+    text: () => Promise.resolve(JSON.stringify(data)),
+    headers: new Headers(),
+  };
+  obj.json = obj.json.bind(obj);
+  obj.text = obj.text.bind(obj);
+  return obj;
+}
+
+function mockFetch() {
+  return (url: string) => {
+    if (url.includes("/api/usage/analytics")) {
+      return Promise.resolve(makeResp(ANALYTICS_RESPONSE));
+    }
+    return Promise.resolve(makeResp({}, 404));
+  };
+}
+
+async function captureOutput(fn: () => Promise<void>): Promise<{ stdout: string; stderr: string }> {
+  const out: string[] = [];
+  const err: string[] = [];
+  const origOut = process.stdout.write.bind(process.stdout);
+  const origErr = process.stderr.write.bind(process.stderr);
+  process.stdout.write = (c: string | Uint8Array) => {
+    out.push(typeof c === "string" ? c : c.toString());
+    return true;
+  };
+  process.stderr.write = (c: string | Uint8Array) => {
+    err.push(typeof c === "string" ? c : c.toString());
+    return true;
+  };
+  try {
+    await fn();
+  } finally {
+    process.stdout.write = origOut;
+    process.stderr.write = origErr;
+  }
+  return { stdout: out.join(""), stderr: err.join("") };
+}
+
+test("runCostCommand exibe tabela com provedores", async () => {
+  const origFetch = globalThis.fetch;
+  globalThis.fetch = mockFetch() as any;
+
+  const { runCostCommand } = await import("../../bin/cli/commands/cost.mjs");
+  const cmd = { optsWithGlobals: () => ({ output: "table", quiet: false }) };
+  const { stdout } = await captureOutput(() =>
+    runCostCommand({ period: "30d", groupBy: "provider", limit: 100 }, cmd as any)
+  );
+
+  globalThis.fetch = origFetch;
+  assert.ok(stdout.includes("openai") || stdout.includes("Group"));
+});
+
+test("runCostCommand --output json retorna array de rows", async () => {
+  const origFetch = globalThis.fetch;
+  globalThis.fetch = mockFetch() as any;
+
+  const { runCostCommand } = await import("../../bin/cli/commands/cost.mjs");
+  const cmd = { optsWithGlobals: () => ({ output: "json", quiet: true }) };
+  const { stdout } = await captureOutput(() =>
+    runCostCommand({ period: "30d", groupBy: "provider", limit: 100 }, cmd as any)
+  );
+
+  globalThis.fetch = origFetch;
+  const parsed = JSON.parse(stdout);
+  assert.ok(Array.isArray(parsed));
+  assert.equal(parsed.length, 2);
+  assert.equal(parsed[0].group, "openai");
+  assert.ok(parsed[0].costUsd > 0);
+  assert.ok(parsed[0].costPct > 0);
+});
+
+test("runCostCommand --group-by model usa byModel do response", async () => {
+  const origFetch = globalThis.fetch;
+  globalThis.fetch = mockFetch() as any;
+
+  const { runCostCommand } = await import("../../bin/cli/commands/cost.mjs");
+  const cmd = { optsWithGlobals: () => ({ output: "json", quiet: true }) };
+  const { stdout } = await captureOutput(() =>
+    runCostCommand({ period: "7d", groupBy: "model", limit: 100 }, cmd as any)
+  );
+
+  globalThis.fetch = origFetch;
+  const parsed = JSON.parse(stdout);
+  assert.ok(Array.isArray(parsed));
+  assert.ok(parsed.some((r: any) => r.group === "gpt-4o"));
+});
+
+test("runCostCommand --group-by day usa byDay do response", async () => {
+  const origFetch = globalThis.fetch;
+  globalThis.fetch = mockFetch() as any;
+
+  const { runCostCommand } = await import("../../bin/cli/commands/cost.mjs");
+  const cmd = { optsWithGlobals: () => ({ output: "json", quiet: true }) };
+  const { stdout } = await captureOutput(() =>
+    runCostCommand({ period: "7d", groupBy: "day", limit: 100 }, cmd as any)
+  );
+
+  globalThis.fetch = origFetch;
+  const parsed = JSON.parse(stdout);
+  assert.ok(Array.isArray(parsed));
+  assert.ok(parsed.some((r: any) => r.group.includes("2026-05")));
+});
+
+test("runCostCommand imprime total em stderr", async () => {
+  const origFetch = globalThis.fetch;
+  globalThis.fetch = mockFetch() as any;
+
+  const { runCostCommand } = await import("../../bin/cli/commands/cost.mjs");
+  const cmd = { optsWithGlobals: () => ({ output: "table", quiet: false }) };
+  const { stderr } = await captureOutput(() =>
+    runCostCommand({ period: "30d", groupBy: "provider", limit: 100 }, cmd as any)
+  );
+
+  globalThis.fetch = origFetch;
+  assert.ok(stderr.includes("Total:") && stderr.includes("$"));
+});
+
+test("runCostCommand --since/--until envia startDate/endDate na query", async () => {
+  let capturedUrl = "";
+  const origFetch = globalThis.fetch;
+  globalThis.fetch = ((url: string) => {
+    capturedUrl = url;
+    return Promise.resolve(makeResp(ANALYTICS_RESPONSE));
+  }) as any;
+
+  const { runCostCommand } = await import("../../bin/cli/commands/cost.mjs");
+  const cmd = { optsWithGlobals: () => ({ output: "json", quiet: true }) };
+  await captureOutput(() =>
+    runCostCommand(
+      { since: "2026-01-01", until: "2026-05-01", groupBy: "provider", limit: 100 },
+      cmd as any
+    )
+  );
+
+  globalThis.fetch = origFetch;
+  assert.ok(capturedUrl.includes("startDate=2026-01-01"));
+  assert.ok(capturedUrl.includes("endDate=2026-05-01"));
+  assert.ok(!capturedUrl.includes("range="));
+});
+
+test("runCostCommand --limit trunca resultado", async () => {
+  const origFetch = globalThis.fetch;
+  globalThis.fetch = mockFetch() as any;
+
+  const { runCostCommand } = await import("../../bin/cli/commands/cost.mjs");
+  const cmd = { optsWithGlobals: () => ({ output: "json", quiet: true }) };
+  const { stdout } = await captureOutput(() =>
+    runCostCommand({ period: "30d", groupBy: "provider", limit: 1 }, cmd as any)
+  );
+
+  globalThis.fetch = origFetch;
+  const parsed = JSON.parse(stdout);
+  assert.equal(parsed.length, 1);
+});