diff --git a/app/pages/pilot-profile-setup.vue b/app/pages/pilot-profile-setup.vue
index 8f0b445..f422c53 100644
--- a/app/pages/pilot-profile-setup.vue
+++ b/app/pages/pilot-profile-setup.vue
@@ -67,7 +67,7 @@
               </div>
 
               <Transition name="fade-slide">
-                <div v-if="answers.simulator === 'other'" class="mt-6">
+                <div v-if="simulatorRequiresOs" class="mt-6">
                   <p class="text-xs uppercase tracking-[0.3em] text-cyan-200/70">Which OS?</p>
                   <div class="mt-3 grid grid-cols-3 gap-3">
                     <button
@@ -105,7 +105,7 @@
               <button
                 type="button"
                 class="btn primary mt-8"
-                :disabled="!answers.simulator || (answers.simulator === 'other' && !answers.os)"
+                :disabled="!answers.simulator || (simulatorRequiresOs && !answers.os)"
                 @click="continueCockpit"
               >
                 Continue
@@ -298,6 +298,7 @@ import {
   MAX_FEATURE_WISHES,
   PRICING_PREFERENCE_OPTIONS,
   ONBOARDING_TOTAL_STEPS,
+  SIMULATORS_REQUIRING_OS,
   createDefaultOnboardingProfile,
 } from '~~/shared/onboarding/config'
 import type { HardwareItem, NetworkExperience, PricingPreference, Simulator, ToolkitItem } from '~~/shared/onboarding/config'
@@ -333,6 +334,7 @@ const progress = computed(() => {
 })
 
 const simulatorLabel = computed(() => SIMULATOR_OPTIONS.find(o => o.value === answers.simulator)?.label || '')
+const simulatorRequiresOs = computed(() => Boolean(answers.simulator && (SIMULATORS_REQUIRING_OS as string[]).includes(answers.simulator)))
 const toolkitLabels = computed(() => TOOLKIT_OPTIONS.filter(o => answers.toolkit.includes(o.value)).map(o => o.label))
 
 function toggleInArray<T>(arr: T[], value: T) {
@@ -372,7 +374,7 @@ function continueCockpit() {
     simulator: answers.simulator,
     hardware: answers.hardware,
   }
-  if (answers.simulator === 'other') {
+  if (simulatorRequiresOs.value) {
     payload.os = answers.os
   }
   saveAnswer(payload)
diff --git a/server/utils/onboardingProfile.test.ts b/server/utils/onboardingProfile.test.ts
index 03549f0..8984ae7 100644
--- a/server/utils/onboardingProfile.test.ts
+++ b/server/utils/onboardingProfile.test.ts
@@ -13,9 +13,11 @@ describe('sanitizeOnboardingUpdate', () => {
     assert.equal('simulator' in result, false)
   })
 
-  it('only keeps os when simulator is other', () => {
+  it('keeps os for non-Windows-only simulators (other, xplane12)', () => {
     const withOther = sanitizeOnboardingUpdate({ simulator: 'other', os: 'linux' })
     assert.equal(withOther.os, 'linux')
+    const withXplane = sanitizeOnboardingUpdate({ simulator: 'xplane12', os: 'mac' })
+    assert.equal(withXplane.os, 'mac')
     const withMsfs = sanitizeOnboardingUpdate({ simulator: 'msfs2024', os: 'linux' })
     assert.equal('os' in withMsfs, false)
   })
diff --git a/server/utils/onboardingProfile.ts b/server/utils/onboardingProfile.ts
index 1cb2a06..89ead49 100644
--- a/server/utils/onboardingProfile.ts
+++ b/server/utils/onboardingProfile.ts
@@ -1,7 +1,7 @@
 import {
   SIMULATOR_OPTIONS, OS_OPTIONS, HARDWARE_OPTIONS, RADIO_PAIN_POINT_OPTIONS,
   NETWORK_OPTIONS, TOOLKIT_OPTIONS, PAID_TOOLKIT_VALUES, TOOLKIT_DURATION_OPTIONS,
-  FEATURE_WISH_OPTIONS, PRICING_PREFERENCE_OPTIONS, MAX_FEATURE_WISHES,
+  FEATURE_WISH_OPTIONS, PRICING_PREFERENCE_OPTIONS, MAX_FEATURE_WISHES, SIMULATORS_REQUIRING_OS,
 } from '~~/shared/onboarding/config'
 import type {
   FeatureWish, HardwareItem, NetworkExperience, OperatingSystem, PricingPreference,
@@ -54,7 +54,7 @@ export interface SanitizedOnboardingUpdate {
   skipped?: boolean
 }
 
-/** WHY: os is only meaningful when simulator === 'other' — MSFS/X-Plane imply Windows/cross-platform already. */
+/** WHY: os is only meaningful for non-Windows-only sims (X-Plane, Other) — MSFS implies Windows already. */
 export function sanitizeOnboardingUpdate(body: OnboardingUpdateInput): SanitizedOnboardingUpdate {
   const result: SanitizedOnboardingUpdate = {}
 
@@ -62,7 +62,12 @@ export function sanitizeOnboardingUpdate(body: OnboardingUpdateInput): Sanitized
     result.simulator = body.simulator as Simulator
   }
 
-  if (result.simulator === 'other' && typeof body.os === 'string' && OS_VALUES.has(body.os as OperatingSystem)) {
+  if (
+    result.simulator &&
+    (SIMULATORS_REQUIRING_OS as Simulator[]).includes(result.simulator) &&
+    typeof body.os === 'string' &&
+    OS_VALUES.has(body.os as OperatingSystem)
+  ) {
     result.os = body.os as OperatingSystem
   }
 
diff --git a/shared/onboarding/config.ts b/shared/onboarding/config.ts
index ac4901b..b546881 100644
--- a/shared/onboarding/config.ts
+++ b/shared/onboarding/config.ts
@@ -34,6 +34,9 @@ export const OS_OPTIONS: OnboardingOption<OperatingSystem>[] = [
   { value: 'linux', label: 'Linux', icon: 'mdi-linux' },
 ]
 
+/** Simulators that aren't Windows-only — asking OS here tells us real platform reach. */
+export const SIMULATORS_REQUIRING_OS: Simulator[] = ['xplane12', 'other']
+
 export const HARDWARE_OPTIONS: OnboardingOption<HardwareItem>[] = [
   { value: 'keyboard_mouse', label: 'Keyboard & mouse', icon: 'mdi-keyboard-outline' },
   { value: 'hotas', label: 'HOTAS / joystick', icon: 'mdi-controller-classic-outline' },