diff --git a/news/changelog-1.9.md b/news/changelog-1.9.md
index ecc77efc65..51f9f904b8 100644
--- a/news/changelog-1.9.md
+++ b/news/changelog-1.9.md
@@ -181,6 +181,7 @@ All changes included in 1.9:
 
 - ([#4426](https://github.com/quarto-dev/quarto-cli/issues/4426)): New `quarto install verapdf` command installs [veraPDF](https://verapdf.org/) for PDF/A and PDF/UA validation. When verapdf is available, PDFs created with the `pdf-standard` option are automatically validated for compliance. Also supports `quarto uninstall verapdf`, `quarto update verapdf`, and `quarto tools`.
 - ([#11877](https://github.com/quarto-dev/quarto-cli/issues/11877), [#10961](https://github.com/quarto-dev/quarto-cli/issues/10961), [#6821](https://github.com/quarto-dev/quarto-cli/issues/6821), [#13704](https://github.com/quarto-dev/quarto-cli/issues/13704)): New `quarto install chrome-headless-shell` command downloads [Chrome Headless Shell](https://developer.chrome.com/blog/chrome-headless-shell) from Google's Chrome for Testing API. This is the recommended headless browser for diagram rendering (Mermaid, Graphviz) to non-HTML formats. Smaller and lighter than full Chrome, with fewer system dependencies.
+- ([#12124](https://github.com/quarto-dev/quarto-cli/issues/12124)): Support `quarto install tinytex` on ARM64 Linux and adopt new TinyTeX naming scheme with `.tar.xz` compression.
 
 ### `preview`
 
diff --git a/src/core/zip.ts b/src/core/zip.ts
index b9bc8170c9..8ed23ddde5 100644
--- a/src/core/zip.ts
+++ b/src/core/zip.ts
@@ -12,7 +12,21 @@ import { safeWindowsExec } from "./windows.ts";
 export function unzip(file: string, dir?: string) {
   if (!dir) dir = dirname(file);
 
-  if (file.endsWith("zip")) {
+  if (isWindows && file.endsWith(".exe")) {
+    // Self-extracting 7z archive (e.g., TinyTeX-windows.exe)
+    return safeWindowsExec(
+      file,
+      ["-y"],
+      (cmd: string[]) => {
+        return execProcess({
+          cmd: cmd[0],
+          args: cmd.slice(1),
+          cwd: dir,
+          stdout: "piped",
+        });
+      },
+    );
+  } else if (file.endsWith("zip")) {
     // It's a zip file
     if (isWindows) {
       const args = [
@@ -51,7 +65,7 @@ export function unzip(file: string, dir?: string) {
       // Otherwise fall back to "tar" in PATH
     }
     return execProcess(
-      { cmd: tarCmd, args: ["xfz", file], cwd: dir, stdout: "piped" },
+      { cmd: tarCmd, args: ["xf", file], cwd: dir, stdout: "piped" },
     );
   }
 }
diff --git a/src/tools/impl/tinytex.ts b/src/tools/impl/tinytex.ts
index ec63840102..cb07917406 100644
--- a/src/tools/impl/tinytex.ts
+++ b/src/tools/impl/tinytex.ts
@@ -33,6 +33,7 @@ import { suggestUserBinPaths } from "../../core/path.ts";
 
 import { ensureDirSync, walkSync } from "../../deno_ral/fs.ts";
 import {
+  arch,
   isLinux,
   isMac,
   isWindows,
@@ -65,15 +66,6 @@ export const tinyTexInstallable: InstallableTool = {
     },
     os: ["darwin"],
     message: "The directory /usr/local/bin is not writable.",
-  }, {
-    check: () => {
-      // Can't be a linux non-x86 platform
-      const needsSource = needsSourceInstall();
-      return Promise.resolve(!needsSource);
-    },
-    os: ["linux"],
-    message:
-      "This platform doesn't support installation at this time. Please install manually instead. See https://yihui.org/tinytex/#installation.",
   }],
   installed,
   installDir,
@@ -161,17 +153,17 @@ async function preparePackage(
   const version = pkgInfo.version;
 
   // target package information
-  const pkgName = tinyTexPkgName(kPackageMaximal, version);
-  const filePath = join(context.workingDir, pkgName);
-
-  // Download the package
-  const url = tinyTexUrl(pkgName, pkgInfo);
-  if (url) {
-    // Download the package
-    await context.download(`TinyTex ${version}`, url, filePath);
+  const candidates = tinyTexPkgName(kPackageMaximal, version);
+  const result = tinyTexUrl(candidates, pkgInfo);
+  if (result) {
+    const filePath = join(context.workingDir, result.name);
+    await context.download(`TinyTex ${version}`, result.url, filePath);
     return { filePath, version };
   } else {
-    context.error("Couldn't determine what URL to use to download");
+    context.error(
+      `Couldn't determine what URL to use to download TinyTeX. ` +
+        `Tried: ${candidates.join(", ")}`,
+    );
     return Promise.reject();
   }
 }
@@ -502,22 +494,55 @@ async function textLiveRepo() {
   return autoUrl;
 }
 
-function tinyTexPkgName(base?: string, ver?: string) {
-  const ext = isWindows ? "zip" : isLinux ? "tar.gz" : "tgz";
+export function tinyTexPkgName(
+  base?: string,
+  ver?: string,
+  options?: { os?: string; arch?: string },
+): string[] {
+  const effectiveOs = options?.os ??
+    (isWindows ? "windows" : isLinux ? "linux" : "darwin");
+  const effectiveArch = options?.arch ?? arch;
 
   base = base || "TinyTeX";
-  if (ver) {
-    return `${base}-${ver}.${ext}`;
+
+  if (!ver) {
+    const ext = effectiveOs === "windows"
+      ? "zip"
+      : effectiveOs === "linux"
+      ? "tar.gz"
+      : "tgz";
+    return [`${base}.${ext}`];
+  }
+
+  const candidates: string[] = [];
+
+  if (effectiveOs === "windows") {
+    candidates.push(`${base}-windows-${ver}.exe`);
+    candidates.push(`${base}-${ver}.zip`);
+  } else if (effectiveOs === "linux") {
+    if (effectiveArch === "aarch64") {
+      candidates.push(`${base}-linux-arm64-${ver}.tar.xz`);
+      candidates.push(`${base}-arm64-${ver}.tar.gz`);
+    } else {
+      candidates.push(`${base}-linux-x86_64-${ver}.tar.xz`);
+      candidates.push(`${base}-${ver}.tar.gz`);
+    }
   } else {
-    return `${base}.${ext}`;
+    candidates.push(`${base}-darwin-${ver}.tar.xz`);
+    candidates.push(`${base}-${ver}.tgz`);
   }
+
+  return candidates;
 }
 
-function tinyTexUrl(pkg: string, remotePkgInfo: RemotePackageInfo) {
-  const asset = remotePkgInfo.assets.find((asset) => {
-    return asset.name === pkg;
-  });
-  return asset?.url;
+function tinyTexUrl(candidates: string[], remotePkgInfo: RemotePackageInfo) {
+  for (const pkg of candidates) {
+    const asset = remotePkgInfo.assets.find((asset) => asset.name === pkg);
+    if (asset) {
+      return { url: asset.url, name: pkg };
+    }
+  }
+  return undefined;
 }
 
 async function remotePackageInfo(): Promise<RemotePackageInfo> {
@@ -537,14 +562,6 @@ async function isWritable(path: string) {
   return status.state === "granted";
 }
 
-function needsSourceInstall() {
-  if (isLinux && Deno.build.arch !== "x86_64") {
-    return true;
-  } else {
-    return false;
-  }
-}
-
 async function isTinyTex() {
   const root = await texLiveRoot();
   if (root) {
diff --git a/tests/unit/tools/tinytex.test.ts b/tests/unit/tools/tinytex.test.ts
new file mode 100644
index 0000000000..5522c1bc7d
--- /dev/null
+++ b/tests/unit/tools/tinytex.test.ts
@@ -0,0 +1,160 @@
+/*
+ * tinytex.test.ts
+ *
+ * Copyright (C) 2026 Posit Software, PBC
+ */
+
+import { unitTest } from "../../test.ts";
+import { assert, assertEquals } from "testing/asserts";
+import { tinyTexPkgName } from "../../../src/tools/impl/tinytex.ts";
+import { getLatestRelease } from "../../../src/tools/github.ts";
+import { GitHubRelease } from "../../../src/tools/types.ts";
+
+// ---- Pure logic tests for tinyTexPkgName ----
+
+unitTest("tinyTexPkgName - Linux aarch64 with version", async () => {
+  assertEquals(
+    tinyTexPkgName("TinyTeX", "v2026.04", { os: "linux", arch: "aarch64" }),
+    [
+      "TinyTeX-linux-arm64-v2026.04.tar.xz",
+      "TinyTeX-arm64-v2026.04.tar.gz",
+    ],
+  );
+});
+
+unitTest("tinyTexPkgName - Linux x86_64 with version", async () => {
+  assertEquals(
+    tinyTexPkgName("TinyTeX", "v2026.04", { os: "linux", arch: "x86_64" }),
+    [
+      "TinyTeX-linux-x86_64-v2026.04.tar.xz",
+      "TinyTeX-v2026.04.tar.gz",
+    ],
+  );
+});
+
+unitTest("tinyTexPkgName - macOS with version", async () => {
+  assertEquals(
+    tinyTexPkgName("TinyTeX", "v2026.04", { os: "darwin", arch: "aarch64" }),
+    [
+      "TinyTeX-darwin-v2026.04.tar.xz",
+      "TinyTeX-v2026.04.tgz",
+    ],
+  );
+});
+
+unitTest("tinyTexPkgName - Windows with version", async () => {
+  assertEquals(
+    tinyTexPkgName("TinyTeX", "v2026.04", { os: "windows", arch: "x86_64" }),
+    [
+      "TinyTeX-windows-v2026.04.exe",
+      "TinyTeX-v2026.04.zip",
+    ],
+  );
+});
+
+unitTest("tinyTexPkgName - versionless Linux aarch64", async () => {
+  assertEquals(
+    tinyTexPkgName("TinyTeX", undefined, { os: "linux", arch: "aarch64" }),
+    ["TinyTeX.tar.gz"],
+  );
+});
+
+unitTest("tinyTexPkgName - TinyTeX-1 ARM64 Linux", async () => {
+  assertEquals(
+    tinyTexPkgName("TinyTeX-1", "v2026.04", {
+      os: "linux",
+      arch: "aarch64",
+    }),
+    [
+      "TinyTeX-1-linux-arm64-v2026.04.tar.xz",
+      "TinyTeX-1-arm64-v2026.04.tar.gz",
+    ],
+  );
+});
+
+unitTest("tinyTexPkgName - default base", async () => {
+  assertEquals(
+    tinyTexPkgName(undefined, "v2026.04", { os: "linux", arch: "x86_64" }),
+    [
+      "TinyTeX-linux-x86_64-v2026.04.tar.xz",
+      "TinyTeX-v2026.04.tar.gz",
+    ],
+  );
+});
+
+// ---- Asset-existence tests (network, verify against latest release) ----
+
+const kTinyTexRepo = "rstudio/tinytex-releases";
+
+let cachedRelease: GitHubRelease | undefined;
+async function getRelease() {
+  if (!cachedRelease) {
+    cachedRelease = await getLatestRelease(kTinyTexRepo);
+  }
+  return cachedRelease;
+}
+
+function assertAssetExists(
+  candidates: string[],
+  assetNames: string[],
+  label: string,
+) {
+  const found = candidates.some((c) => assetNames.includes(c));
+  assert(
+    found,
+    `No matching asset for ${label}. Candidates: ${candidates.join(", ")}. ` +
+      `Available TinyTeX assets: ${assetNames.filter((a) => a.startsWith("TinyTeX")).join(", ")}`,
+  );
+}
+
+unitTest(
+  "tinyTexPkgName - Linux x86_64 candidates match latest release",
+  async () => {
+    const release = await getRelease();
+    const assetNames = release.assets.map((a) => a.name);
+    const candidates = tinyTexPkgName("TinyTeX", release.tag_name, {
+      os: "linux",
+      arch: "x86_64",
+    });
+    assertAssetExists(candidates, assetNames, "Linux x86_64");
+  },
+);
+
+unitTest(
+  "tinyTexPkgName - Linux aarch64 candidates match latest release",
+  async () => {
+    const release = await getRelease();
+    const assetNames = release.assets.map((a) => a.name);
+    const candidates = tinyTexPkgName("TinyTeX", release.tag_name, {
+      os: "linux",
+      arch: "aarch64",
+    });
+    assertAssetExists(candidates, assetNames, "Linux aarch64");
+  },
+);
+
+unitTest(
+  "tinyTexPkgName - macOS candidates match latest release",
+  async () => {
+    const release = await getRelease();
+    const assetNames = release.assets.map((a) => a.name);
+    const candidates = tinyTexPkgName("TinyTeX", release.tag_name, {
+      os: "darwin",
+      arch: "aarch64",
+    });
+    assertAssetExists(candidates, assetNames, "macOS");
+  },
+);
+
+unitTest(
+  "tinyTexPkgName - Windows candidates match latest release",
+  async () => {
+    const release = await getRelease();
+    const assetNames = release.assets.map((a) => a.name);
+    const candidates = tinyTexPkgName("TinyTeX", release.tag_name, {
+      os: "windows",
+      arch: "x86_64",
+    });
+    assertAssetExists(candidates, assetNames, "Windows");
+  },
+);