diff --git a/scripts/check-cli-startup-memory.mjs b/scripts/check-cli-startup-memory.mjs
index 0a56146531b2..3819be7e67d6 100644
--- a/scripts/check-cli-startup-memory.mjs
+++ b/scripts/check-cli-startup-memory.mjs
@@ -62,11 +62,18 @@ function parseArgs(argv) {
   return options;
 }
 
-const DEFAULT_LIMITS_MB = {
-  help: 100,
-  statusJson: 400,
-  gatewayStatus: 500,
-};
+function resolveDefaultLimitsMb(platform = process.platform) {
+  return {
+    // Linux CI is the tight startup regression signal. macOS consistently reports
+    // higher RSS for the same launcher path, so keep it supported without hiding
+    // Linux help-path regressions.
+    help: platform === "darwin" ? 300 : 100,
+    statusJson: 400,
+    gatewayStatus: 500,
+  };
+}
+
+const DEFAULT_LIMITS_MB = resolveDefaultLimitsMb();
 
 const cases = [
   {
@@ -334,6 +341,7 @@ function runStartupMemoryCheck(argv = process.argv.slice(2), params = {}) {
 export const testing = {
   cases,
   parseArgs,
+  resolveDefaultLimitsMb,
   runCase,
   runStartupMemoryCheck,
 };
diff --git a/test/scripts/check-cli-startup-memory.test.ts b/test/scripts/check-cli-startup-memory.test.ts
index 67c409710b46..8e45d3118f35 100644
--- a/test/scripts/check-cli-startup-memory.test.ts
+++ b/test/scripts/check-cli-startup-memory.test.ts
@@ -20,6 +20,11 @@ afterEach(() => {
 });
 
 describe("check-cli-startup-memory", () => {
+  it("keeps the Linux help startup budget tight while allowing macOS RSS overhead", () => {
+    expect(testing.resolveDefaultLimitsMb("linux").help).toBe(100);
+    expect(testing.resolveDefaultLimitsMb("darwin").help).toBeGreaterThan(100);
+  });
+
   it("does not create a temp home before argument validation succeeds", () => {
     if (process.platform !== "darwin" && process.platform !== "linux") {
       return;