diff --git a/.changeset/doctor-shell-detection.md b/.changeset/doctor-shell-detection.md
new file mode 100644
index 00000000..456bd881
--- /dev/null
+++ b/.changeset/doctor-shell-detection.md
@@ -0,0 +1,5 @@
+---
+"clerk": patch
+---
+
+Fix shell detection for fish users whose login shell is zsh. `clerk doctor` now correctly identifies fish via `FISH_VERSION`, and `clerk update` no longer shows an irrelevant `hash -r` hint.
diff --git a/packages/cli-core/src/commands/doctor/checks.ts b/packages/cli-core/src/commands/doctor/checks.ts
index 5cf086ef..b8bf9afa 100644
--- a/packages/cli-core/src/commands/doctor/checks.ts
+++ b/packages/cli-core/src/commands/doctor/checks.ts
@@ -362,8 +362,11 @@ export async function checkCliVersion(): Promise<CheckResult> {
 type DetectedShell = "bash" | "zsh" | "fish";
 
 function detectShell(): DetectedShell | null {
+  // FISH_VERSION is set by fish itself, so it's a stronger signal than $SHELL — which only reflects
+  // the login shell and won't follow an interactive `chsh`-less switch into fish.
+  if (process.env.FISH_VERSION) return "fish";
   const name = process.env.SHELL?.split("/").pop();
-  if (name === "zsh" || name === "bash" || name === "fish") return name;
+  if (name === "bash" || name === "zsh" || name === "fish") return name;
   return null;
 }
 
diff --git a/packages/cli-core/src/commands/doctor/doctor.test.ts b/packages/cli-core/src/commands/doctor/doctor.test.ts
index 09b6860d..bad4c48b 100644
--- a/packages/cli-core/src/commands/doctor/doctor.test.ts
+++ b/packages/cli-core/src/commands/doctor/doctor.test.ts
@@ -156,6 +156,7 @@ beforeEach(async () => {
   tempDir = await mkdtemp(join(tmpdir(), "clerk-doctor-test-"));
   process.cwd = () => tempDir;
   process.env = { ...originalEnv };
+  delete process.env.FISH_VERSION;
   process.env.CLERK_PLATFORM_API_KEY = "test_key";
 
   mockUserInfo = null;
@@ -739,6 +740,43 @@ describe("checkShellCompletion", () => {
     });
   });
 
+  test("detects fish via FISH_VERSION when SHELL is unset", async () => {
+    process.env.SHELL = "";
+    process.env.FISH_VERSION = "3.7.0";
+    process.env.HOME = tempDir;
+    const result = await checkShellCompletion();
+    expectCheck(result, {
+      name: "Shell completion",
+      status: "warn",
+      message: "fish",
+      remedy: "clerk completion fish",
+    });
+  });
+
+  test("prefers FISH_VERSION over SHELL when both are set", async () => {
+    process.env.SHELL = "/bin/zsh";
+    process.env.FISH_VERSION = "3.7.0";
+    process.env.HOME = tempDir;
+    const result = await checkShellCompletion();
+    expectCheck(result, {
+      name: "Shell completion",
+      status: "warn",
+      message: "fish",
+      remedy: "clerk completion fish",
+    });
+  });
+
+  test("skips when SHELL points to an unrecognized shell", async () => {
+    process.env.SHELL = "/bin/csh";
+    process.env.HOME = tempDir;
+    const result = await checkShellCompletion();
+    expectCheck(result, {
+      name: "Shell completion",
+      status: "pass",
+      message: "skipped",
+    });
+  });
+
   test("no fix action attached (completions are not auto-fixable)", async () => {
     process.env.SHELL = "/bin/zsh";
     process.env.HOME = tempDir;
diff --git a/packages/cli-core/src/commands/update/index.ts b/packages/cli-core/src/commands/update/index.ts
index 99f6222e..8876fcb6 100644
--- a/packages/cli-core/src/commands/update/index.ts
+++ b/packages/cli-core/src/commands/update/index.ts
@@ -207,7 +207,7 @@ function hashHint(): string | null {
   // but return early to be explicit.
   if (process.platform === "win32") return null;
   const shell = (process.env.SHELL ?? "").toLowerCase();
-  if (shell.endsWith("/fish")) return null; // auto-rehashes
+  if (shell.endsWith("/fish") || process.env.FISH_VERSION) return null; // auto-rehashes
   // pwsh can run on Linux/macOS via $SHELL=/usr/bin/pwsh; no command-hash cache.
   if (shell.endsWith("/pwsh")) return null;
   if (shell.endsWith("/tcsh") || shell.endsWith("/csh")) {