diff --git a/composeApp/src/commonMain/kotlin/com/nuvio/app/core/auth/AuthRepository.kt b/composeApp/src/commonMain/kotlin/com/nuvio/app/core/auth/AuthRepository.kt
index 11c318fc6..169f2c6f8 100644
--- a/composeApp/src/commonMain/kotlin/com/nuvio/app/core/auth/AuthRepository.kt
+++ b/composeApp/src/commonMain/kotlin/com/nuvio/app/core/auth/AuthRepository.kt
@@ -7,6 +7,7 @@ import com.nuvio.app.core.storage.LocalAccountDataCleaner
 import io.github.jan.supabase.auth.auth
 import io.github.jan.supabase.auth.providers.builtin.Email
 import io.github.jan.supabase.auth.status.SessionStatus
+import io.github.jan.supabase.exceptions.RestException
 import io.github.jan.supabase.functions.functions
 import kotlin.uuid.ExperimentalUuidApi
 import kotlin.uuid.Uuid
@@ -32,6 +33,7 @@ object AuthRepository {
     val error: StateFlow<String?> = _error.asStateFlow()
 
     private var initialized = false
+    private var validatedRemoteUserId: String? = null
 
     fun initialize() {
         if (initialized) return
@@ -40,6 +42,7 @@ object AuthRepository {
         scope.launch {
             SyncBackendRepository.state.collectLatest { backendState ->
                 if (!backendState.isLoaded) return@collectLatest
+                validatedRemoteUserId = null
 
                 AuthStorage.loadAnonymousUserId()?.let { savedAnonId ->
                     _state.value = AuthState.Authenticated(
@@ -56,8 +59,10 @@ object AuthRepository {
                     when (status) {
                         is SessionStatus.Authenticated -> {
                             val user = status.session.user
+                            val userId = user?.id.orEmpty()
+                            if (!validateRemoteSession(userId)) return@collect
                             _state.value = AuthState.Authenticated(
-                                userId = user?.id ?: "",
+                                userId = userId,
                                 email = user?.email,
                                 isAnonymous = false,
                             )
@@ -79,6 +84,25 @@ object AuthRepository {
         }
     }
 
+    private suspend fun validateRemoteSession(userId: String): Boolean {
+        if (userId.isBlank() || validatedRemoteUserId == userId) return true
+
+        return runCatching {
+            SupabaseProvider.client.auth.retrieveUserForCurrentSession(false)
+            validatedRemoteUserId = userId
+            true
+        }.getOrElse { e ->
+            if (isInvalidRemoteSessionError(e)) {
+                log.w(e) { "Stored Supabase session no longer belongs to an active account; clearing local auth" }
+                clearLocalSessionAfterRemoteInvalidation()
+                false
+            } else {
+                log.w(e) { "Unable to validate stored Supabase session; keeping cached auth state" }
+                true
+            }
+        }
+    }
+
     @OptIn(ExperimentalUuidApi::class)
     fun signInAnonymously() {
         _error.value = null
@@ -118,6 +142,7 @@ object AuthRepository {
         _error.value = null
         val wasAnonymous = AuthStorage.loadAnonymousUserId() != null
         AuthStorage.clearAnonymousUserId()
+        validatedRemoteUserId = null
         if (!wasAnonymous) {
             SupabaseProvider.client.auth.signOut()
         }
@@ -128,10 +153,32 @@ object AuthRepository {
         _error.value = e.message ?: getString(Res.string.auth_sign_out_failed)
     }
 
+    suspend fun signOutIfSessionInvalid(error: Throwable, source: String): Boolean {
+        if (!isInvalidRemoteSessionError(error)) return false
+
+        log.w(error) { "$source failed because the current Supabase account/session is no longer valid; clearing local auth" }
+        clearLocalSessionAfterRemoteInvalidation()
+        return true
+    }
+
+    private suspend fun clearLocalSessionAfterRemoteInvalidation() {
+        _error.value = null
+        AuthStorage.clearAnonymousUserId()
+        validatedRemoteUserId = null
+        runCatching {
+            SupabaseProvider.client.auth.clearSession()
+        }.onFailure { e ->
+            log.w(e) { "Failed to clear Supabase session after remote invalidation; continuing local reset" }
+        }
+        _state.value = AuthState.Unauthenticated
+        LocalAccountDataCleaner.wipe()
+    }
+
     suspend fun resetForSyncBackendChange(): Result<Unit> = runCatching {
         _error.value = null
         val wasAnonymous = AuthStorage.loadAnonymousUserId() != null
         AuthStorage.clearAnonymousUserId()
+        validatedRemoteUserId = null
 
         if (!wasAnonymous) {
             runCatching {
@@ -152,6 +199,8 @@ object AuthRepository {
         _error.value = null
         SupabaseProvider.client.functions.invoke("delete-account")
         SupabaseProvider.client.auth.signOut()
+        validatedRemoteUserId = null
+        _state.value = AuthState.Unauthenticated
         LocalAccountDataCleaner.wipe()
     }.onFailure { e ->
         log.e(e) { "Account deletion failed" }
@@ -161,4 +210,39 @@ object AuthRepository {
     fun clearError() {
         _error.value = null
     }
+
+    private fun isInvalidRemoteSessionError(error: Throwable): Boolean {
+        val restError = error.findCause<RestException>()
+        if (restError?.statusCode == 401 || restError?.statusCode == 403) return true
+
+        val message = buildString {
+            append(error.message.orEmpty())
+            if (restError != null) {
+                append(' ')
+                append(restError.error)
+                append(' ')
+                append(restError.description)
+            }
+        }.lowercase()
+
+        return (
+            "jwt" in message &&
+                ("invalid" in message || "expired" in message || "malformed" in message)
+            ) || (
+            "user" in message &&
+                ("does not exist" in message || "not found" in message || "deleted" in message)
+            ) || (
+            "foreign key" in message &&
+                ("auth.users" in message || "user_id" in message)
+            )
+    }
+
+    private inline fun <reified T : Throwable> Throwable.findCause(): T? {
+        var current: Throwable? = this
+        while (current != null) {
+            if (current is T) return current
+            current = current.cause
+        }
+        return null
+    }
 }
diff --git a/composeApp/src/commonMain/kotlin/com/nuvio/app/features/profiles/ProfileRepository.kt b/composeApp/src/commonMain/kotlin/com/nuvio/app/features/profiles/ProfileRepository.kt
index 7644ec63d..cbc1c5545 100644
--- a/composeApp/src/commonMain/kotlin/com/nuvio/app/features/profiles/ProfileRepository.kt
+++ b/composeApp/src/commonMain/kotlin/com/nuvio/app/features/profiles/ProfileRepository.kt
@@ -120,7 +120,7 @@ object ProfileRepository {
             }
             return
         }
-        runCatching {
+        try {
             val result = SupabaseProvider.client.postgrest.rpc("sync_pull_profiles")
             val profiles = result.decodeList<NuvioProfile>()
             _state.value = _state.value.copy(
@@ -133,7 +133,8 @@ object ProfileRepository {
                 activeProfileIndex = _state.value.activeProfile!!.profileIndex
             }
             persist()
-        }.onFailure { e ->
+        } catch (e: Throwable) {
+            if (AuthRepository.signOutIfSessionInvalid(e, "Profile pull")) return
             log.e(e) { "Failed to pull profiles" }
             if (!_state.value.isLoaded) {
                 _state.value = _state.value.copy(isLoaded = true)
@@ -182,13 +183,14 @@ object ProfileRepository {
             applyPayloadsLocally(profiles)
             return
         }
-        runCatching {
+        try {
             val params = buildJsonObject {
                 put("p_profiles", json.encodeToJsonElement(profiles))
             }
             SupabaseProvider.client.postgrest.rpc("sync_push_profiles", params)
             pullProfiles()
-        }.onFailure { e ->
+        } catch (e: Throwable) {
+            if (AuthRepository.signOutIfSessionInvalid(e, "Profile push")) return
             log.e(e) { "Failed to push profiles" }
         }
     }
@@ -273,11 +275,12 @@ object ProfileRepository {
             persist()
             return
         }
-        runCatching {
+        try {
             val params = buildJsonObject { put("p_profile_id", profileIndex) }
             SupabaseProvider.client.postgrest.rpc("sync_delete_profile_data", params)
             pullProfiles()
-        }.onFailure { e ->
+        } catch (e: Throwable) {
+            if (AuthRepository.signOutIfSessionInvalid(e, "Profile delete")) return
             log.e(e) { "Failed to delete profile $profileIndex" }
         }
     }