diff --git a/x-pack/plugins/fleet/common/types/models/agent.ts b/x-pack/plugins/fleet/common/types/models/agent.ts
index 34f68fc34c502..256dd76c41ca4 100644
--- a/x-pack/plugins/fleet/common/types/models/agent.ts
+++ b/x-pack/plugins/fleet/common/types/models/agent.ts
@@ -79,6 +79,8 @@ export interface AgentAction extends NewAgentAction {
 export interface AgentMetadata {
   [x: string]: any;
 }
+
+// SO definition for this type is declared in server/types/interfaces
 interface AgentBase {
   type: AgentType;
   active: boolean;
@@ -124,10 +126,6 @@ export interface Agent extends AgentBase {
   metrics?: AgentMetrics;
 }
 
-export interface AgentSOAttributes extends AgentBase {
-  packages?: string[];
-}
-
 export interface CurrentUpgrade {
   actionId: string;
   complete: boolean;
diff --git a/x-pack/plugins/fleet/common/types/models/agent_policy.ts b/x-pack/plugins/fleet/common/types/models/agent_policy.ts
index 30737d2b2052f..a701d4653f242 100644
--- a/x-pack/plugins/fleet/common/types/models/agent_policy.ts
+++ b/x-pack/plugins/fleet/common/types/models/agent_policy.ts
@@ -36,6 +36,7 @@ export interface NewAgentPolicy {
   is_protected?: boolean;
 }
 
+// SO definition for this type is declared in server/types/interfaces
 export interface AgentPolicy extends Omit<NewAgentPolicy, 'id'> {
   id: string;
   status: ValueOf<AgentPolicyStatus>;
@@ -48,8 +49,6 @@ export interface AgentPolicy extends Omit<NewAgentPolicy, 'id'> {
   is_protected: boolean;
 }
 
-export type AgentPolicySOAttributes = Omit<AgentPolicy, 'id'>;
-
 export interface FullAgentPolicyInputStream {
   id: string;
   data_stream: {
diff --git a/x-pack/plugins/fleet/common/types/models/enrollment_api_key.ts b/x-pack/plugins/fleet/common/types/models/enrollment_api_key.ts
index 5c5568f7dad42..4398675831b45 100644
--- a/x-pack/plugins/fleet/common/types/models/enrollment_api_key.ts
+++ b/x-pack/plugins/fleet/common/types/models/enrollment_api_key.ts
@@ -5,6 +5,7 @@
  * 2.0.
  */
 
+// SO definition for this type is declared in server/types/interfaces
 export interface EnrollmentAPIKey {
   id: string;
   api_key_id: string;
@@ -15,8 +16,6 @@ export interface EnrollmentAPIKey {
   created_at: string;
 }
 
-export type EnrollmentAPIKeySOAttributes = Omit<EnrollmentAPIKey, 'id'>;
-
 // Generated
 
 /**
diff --git a/x-pack/plugins/fleet/common/types/models/fleet_proxy.ts b/x-pack/plugins/fleet/common/types/models/fleet_proxy.ts
index bad53dacdff93..1c69b4db9fbfa 100644
--- a/x-pack/plugins/fleet/common/types/models/fleet_proxy.ts
+++ b/x-pack/plugins/fleet/common/types/models/fleet_proxy.ts
@@ -14,6 +14,7 @@ interface BaseFleetProxy {
   is_preconfigured: boolean;
 }
 
+// SO definition for this type is declared in server/types/interfaces
 export interface NewFleetProxy extends BaseFleetProxy {
   proxy_headers?: Record<string, string | number | boolean> | null;
 }
@@ -21,7 +22,3 @@ export interface NewFleetProxy extends BaseFleetProxy {
 export interface FleetProxy extends NewFleetProxy {
   id: string;
 }
-
-export interface FleetProxySOAttributes extends BaseFleetProxy {
-  proxy_headers?: string | null;
-}
diff --git a/x-pack/plugins/fleet/common/types/models/fleet_server_policy_config.ts b/x-pack/plugins/fleet/common/types/models/fleet_server_policy_config.ts
index 8b7c2ffc0913f..5609853a4ad2e 100644
--- a/x-pack/plugins/fleet/common/types/models/fleet_server_policy_config.ts
+++ b/x-pack/plugins/fleet/common/types/models/fleet_server_policy_config.ts
@@ -5,6 +5,7 @@
  * 2.0.
  */
 
+// SO definition for this type is declared in server/types/interfaces
 export interface NewFleetServerHost {
   name: string;
   host_urls: string[];
@@ -16,5 +17,3 @@ export interface NewFleetServerHost {
 export interface FleetServerHost extends NewFleetServerHost {
   id: string;
 }
-
-export type FleetServerHostSOAttributes = NewFleetServerHost;
diff --git a/x-pack/plugins/fleet/common/types/models/output.ts b/x-pack/plugins/fleet/common/types/models/output.ts
index f8836dae58470..665498cf8f322 100644
--- a/x-pack/plugins/fleet/common/types/models/output.ts
+++ b/x-pack/plugins/fleet/common/types/models/output.ts
@@ -30,11 +30,6 @@ export interface NewOutput {
   allow_edit?: string[];
 }
 
-export type OutputSOAttributes = NewOutput & {
-  output_id?: string;
-  ssl?: string | null; // encrypted ssl field
-};
-
 export type Output = NewOutput & {
   id: string;
 };
diff --git a/x-pack/plugins/fleet/common/types/models/package_policy.ts b/x-pack/plugins/fleet/common/types/models/package_policy.ts
index fe4013c522be7..63c55952f6257 100644
--- a/x-pack/plugins/fleet/common/types/models/package_policy.ts
+++ b/x-pack/plugins/fleet/common/types/models/package_policy.ts
@@ -92,6 +92,7 @@ export interface UpdatePackagePolicy extends NewPackagePolicy {
   version?: string;
 }
 
+// SO definition for this type is declared in server/types/interfaces
 export interface PackagePolicy extends Omit<NewPackagePolicy, 'inputs'> {
   id: string;
   inputs: PackagePolicyInput[];
@@ -105,8 +106,6 @@ export interface PackagePolicy extends Omit<NewPackagePolicy, 'inputs'> {
   created_by: string;
 }
 
-export type PackagePolicySOAttributes = Omit<PackagePolicy, 'id' | 'version'>;
-
 export type DryRunPackagePolicy = NewPackagePolicy & {
   errors?: Array<{ key: string | undefined; message: string }>;
   missingVars?: string[];
diff --git a/x-pack/plugins/fleet/common/types/models/settings.ts b/x-pack/plugins/fleet/common/types/models/settings.ts
index c70fa944e6c24..01f95146e3621 100644
--- a/x-pack/plugins/fleet/common/types/models/settings.ts
+++ b/x-pack/plugins/fleet/common/types/models/settings.ts
@@ -5,8 +5,6 @@
  * 2.0.
  */
 
-import type { SavedObjectAttributes } from '@kbn/core/public';
-
 export interface BaseSettings {
   has_seen_add_data_notice?: boolean;
   fleet_server_hosts?: string[];
@@ -17,5 +15,3 @@ export interface Settings extends BaseSettings {
   id: string;
   preconfigured_fields?: Array<'fleet_server_hosts'>;
 }
-
-export interface SettingsSOAttributes extends BaseSettings, SavedObjectAttributes {}
diff --git a/x-pack/plugins/fleet/server/integration_tests/cloud_preconfiguration.test.ts b/x-pack/plugins/fleet/server/integration_tests/cloud_preconfiguration.test.ts
index f021becf6f444..20b9e25e7994a 100644
--- a/x-pack/plugins/fleet/server/integration_tests/cloud_preconfiguration.test.ts
+++ b/x-pack/plugins/fleet/server/integration_tests/cloud_preconfiguration.test.ts
@@ -15,8 +15,11 @@ import {
 } from '@kbn/core-test-helpers-kbn-server';
 
 import { AGENT_POLICY_INDEX } from '../../common';
-import type { PackagePolicySOAttributes, OutputSOAttributes } from '../../common/types';
-import type { AgentPolicySOAttributes } from '../types';
+import type {
+  AgentPolicySOAttributes,
+  PackagePolicySOAttributes,
+  OutputSOAttributes,
+} from '../types';
 
 import { useDockerRegistry, waitForFleetSetup } from './helpers';
 import {
diff --git a/x-pack/plugins/fleet/server/services/agent_policy.ts b/x-pack/plugins/fleet/server/services/agent_policy.ts
index 96b53da7cbb6c..b69b8ba631423 100644
--- a/x-pack/plugins/fleet/server/services/agent_policy.ts
+++ b/x-pack/plugins/fleet/server/services/agent_policy.ts
@@ -398,7 +398,10 @@ class AgentPolicyService {
     const filter = kuery ? normalizeKuery(SAVED_OBJECT_TYPE, kuery) : undefined;
     let agentPoliciesSO;
     try {
-      agentPoliciesSO = await soClient.find<AgentPolicySOAttributes>({ ...baseFindParams, filter });
+      agentPoliciesSO = await soClient.find<AgentPolicySOAttributes>({
+        ...baseFindParams,
+        filter,
+      });
     } catch (e) {
       const isBadRequest = e.output?.statusCode === 400;
       const isKQLSyntaxError = e.message?.startsWith('KQLSyntaxError');
diff --git a/x-pack/plugins/fleet/server/services/agents/saved_objects.ts b/x-pack/plugins/fleet/server/services/agents/saved_objects.ts
deleted file mode 100644
index 596c7db5d8472..0000000000000
--- a/x-pack/plugins/fleet/server/services/agents/saved_objects.ts
+++ /dev/null
@@ -1,26 +0,0 @@
-/*
- * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
- * or more contributor license agreements. Licensed under the Elastic License
- * 2.0; you may not use this file except in compliance with the Elastic License
- * 2.0.
- */
-
-import type { SavedObject } from '@kbn/core/server';
-
-import type { Agent, AgentSOAttributes } from '../../types';
-
-export function savedObjectToAgent(so: SavedObject<AgentSOAttributes>): Agent {
-  if (so.error) {
-    throw new Error(so.error.message);
-  }
-
-  return {
-    id: so.id,
-    ...so.attributes,
-    local_metadata: so.attributes.local_metadata,
-    user_provided_metadata: so.attributes.user_provided_metadata,
-    access_api_key: undefined,
-    status: undefined,
-    packages: so.attributes.packages ?? [],
-  };
-}
diff --git a/x-pack/plugins/fleet/server/services/epm/packages/get.test.ts b/x-pack/plugins/fleet/server/services/epm/packages/get.test.ts
index e4cd54f90973d..14fe84796b9fd 100644
--- a/x-pack/plugins/fleet/server/services/epm/packages/get.test.ts
+++ b/x-pack/plugins/fleet/server/services/epm/packages/get.test.ts
@@ -11,7 +11,8 @@ import { SavedObjectsErrorHelpers } from '@kbn/core/server';
 import { savedObjectsClientMock } from '@kbn/core/server/mocks';
 
 import { PACKAGES_SAVED_OBJECT_TYPE, PACKAGE_POLICY_SAVED_OBJECT_TYPE } from '../../../../common';
-import type { PackagePolicySOAttributes, RegistryPackage } from '../../../../common/types';
+import type { RegistryPackage } from '../../../../common/types';
+import type { PackagePolicySOAttributes } from '../../../types';
 
 import { createAppContextStartContractMock } from '../../../mocks';
 import { appContextService } from '../../app_context';
diff --git a/x-pack/plugins/fleet/server/services/epm/packages/get.ts b/x-pack/plugins/fleet/server/services/epm/packages/get.ts
index 351128af7f4bf..696aa6a272970 100644
--- a/x-pack/plugins/fleet/server/services/epm/packages/get.ts
+++ b/x-pack/plugins/fleet/server/services/epm/packages/get.ts
@@ -16,11 +16,7 @@ import {
   SO_SEARCH_LIMIT,
 } from '../../../../common/constants';
 import { isPackageLimited } from '../../../../common/services';
-import type {
-  PackageUsageStats,
-  PackagePolicySOAttributes,
-  Installable,
-} from '../../../../common/types';
+import type { PackageUsageStats, Installable } from '../../../../common/types';
 import { PACKAGES_SAVED_OBJECT_TYPE } from '../../../constants';
 import type {
   ArchivePackage,
@@ -28,7 +24,7 @@ import type {
   EpmPackageAdditions,
   GetCategoriesRequest,
 } from '../../../../common/types';
-import type { Installation, PackageInfo } from '../../../types';
+import type { Installation, PackageInfo, PackagePolicySOAttributes } from '../../../types';
 import {
   FleetError,
   PackageFailedVerificationError,
diff --git a/x-pack/plugins/fleet/server/services/output.ts b/x-pack/plugins/fleet/server/services/output.ts
index e6ed4d2d4986f..8666330f6640f 100644
--- a/x-pack/plugins/fleet/server/services/output.ts
+++ b/x-pack/plugins/fleet/server/services/output.ts
@@ -164,7 +164,7 @@ async function validateTypeChanges(
   soClient: SavedObjectsClientContract,
   esClient: ElasticsearchClient,
   id: string,
-  data: Partial<Output>,
+  data: Nullable<Partial<OutputSOAttributes>>,
   originalOutput: Output,
   defaultDataOutputId: string | null,
   fromPreconfiguration: boolean
@@ -194,18 +194,18 @@ async function validateTypeChanges(
 async function updateFleetServerPoliciesDataOutputId(
   soClient: SavedObjectsClientContract,
   esClient: ElasticsearchClient,
-  data: Partial<Output>,
+  data: Nullable<Partial<OutputSOAttributes>>,
   isDefault: boolean,
   defaultDataOutputId: string | null,
   fleetServerPolicies: AgentPolicy[],
   fromPreconfiguration: boolean
 ) {
   // if a logstash output is updated to become default
-  // if fleet server policies are don't have data_output_id or if they are using the new output
+  // if fleet server policies don't have data_output_id
   // update them to use the default output
   if (data?.type === outputType.Logstash && isDefault) {
     for (const policy of fleetServerPolicies) {
-      if (!policy.data_output_id || policy.data_output_id === data?.id) {
+      if (!policy.data_output_id) {
         await agentPolicyService.update(
           soClient,
           esClient,
@@ -582,7 +582,7 @@ class OutputService {
       soClient,
       esClient,
       id,
-      data,
+      updateData,
       originalOutput,
       defaultDataOutputId,
       fromPreconfiguration
diff --git a/x-pack/plugins/fleet/server/services/settings.ts b/x-pack/plugins/fleet/server/services/settings.ts
index 5b48ee8177885..2b5d228ffc97e 100644
--- a/x-pack/plugins/fleet/server/services/settings.ts
+++ b/x-pack/plugins/fleet/server/services/settings.ts
@@ -10,7 +10,8 @@ import type { SavedObjectsClientContract } from '@kbn/core/server';
 
 import { normalizeHostsForAgents } from '../../common/services';
 import { GLOBAL_SETTINGS_SAVED_OBJECT_TYPE, GLOBAL_SETTINGS_ID } from '../../common/constants';
-import type { SettingsSOAttributes, Settings, BaseSettings } from '../../common/types';
+import type { Settings, BaseSettings } from '../../common/types';
+import type { SettingsSOAttributes } from '../types';
 
 import { appContextService } from './app_context';
 import { listFleetServerHosts } from './fleet_server_host';
diff --git a/x-pack/plugins/fleet/server/types/index.tsx b/x-pack/plugins/fleet/server/types/index.tsx
index a89405eb54f05..1f669f07d1433 100644
--- a/x-pack/plugins/fleet/server/types/index.tsx
+++ b/x-pack/plugins/fleet/server/types/index.tsx
@@ -8,7 +8,6 @@
 export type {
   Agent,
   AgentMetadata,
-  AgentSOAttributes,
   AgentStatus,
   AgentType,
   AgentAction,
@@ -22,12 +21,10 @@ export type {
   NewPackagePolicy,
   UpdatePackagePolicy,
   DryRunPackagePolicy,
-  PackagePolicySOAttributes,
   FullAgentPolicyInput,
   FullAgentPolicy,
   FullAgentPolicyOutput,
   AgentPolicy,
-  AgentPolicySOAttributes,
   NewAgentPolicy,
   PreconfiguredAgentPolicy,
   AgentPolicyStatus,
@@ -35,16 +32,12 @@ export type {
   ShipperOutput,
   Output,
   NewOutput,
-  OutputSOAttributes,
   OutputType,
   EnrollmentAPIKey,
-  EnrollmentAPIKeySOAttributes,
   NewFleetServerHost,
   FleetServerHost,
-  FleetServerHostSOAttributes,
   NewFleetProxy,
   FleetProxy,
-  FleetProxySOAttributes,
   Installation,
   EpmPackageInstallStatus,
   InstallationStatus,
@@ -73,7 +66,6 @@ export type {
   TemplateMap,
   TemplateMapEntry,
   Settings,
-  SettingsSOAttributes,
   InstallType,
   InstallSource,
   InstallResult,
@@ -119,4 +111,5 @@ export interface PackageVerificationResult {
 export * from './models';
 export * from './rest_spec';
 export * from './extensions';
+export * from './so_attributes';
 export type { FleetRequestHandler, FleetRequestHandlerContext } from './request_context';
diff --git a/x-pack/plugins/fleet/server/types/so_attributes.ts b/x-pack/plugins/fleet/server/types/so_attributes.ts
new file mode 100644
index 0000000000000..bdc8cf2886fe5
--- /dev/null
+++ b/x-pack/plugins/fleet/server/types/so_attributes.ts
@@ -0,0 +1,143 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+// Definitions for SO attributes. They mirror the types defined under /common/types/models
+import type { agentPolicyStatuses } from '../../common/constants';
+import type {
+  MonitoringType,
+  ValueOf,
+  AgentMetadata,
+  OutputType,
+  ShipperOutput,
+} from '../../common/types';
+import type { AgentType, FleetServerAgentComponent } from '../../common/types/models';
+
+import type {
+  PackagePolicy,
+  PackagePolicyInput,
+  PackagePolicyPackage,
+  PackagePolicyConfigRecord,
+} from '../../common/types/models/package_policy';
+import type { PolicySecretReference } from '../../common/types/models/secret';
+
+export type AgentPolicyStatus = typeof agentPolicyStatuses;
+
+export interface AgentPolicySOAttributes {
+  name: string;
+  namespace: string;
+  is_managed: boolean; // required for created policy
+  updated_at: string;
+  updated_by: string;
+  revision: number;
+  is_protected: boolean;
+  description?: string;
+  is_default?: boolean;
+  is_default_fleet_server?: boolean; // Optional when creating a policy
+  has_fleet_server?: boolean;
+  monitoring_enabled?: MonitoringType;
+  unenroll_timeout?: number;
+  inactivity_timeout?: number;
+  is_preconfigured?: boolean;
+  // Nullable to allow user to reset to default outputs
+  data_output_id?: string | null;
+  monitoring_output_id?: string | null;
+  download_source_id?: string | null;
+  fleet_server_host_id?: string | null;
+  schema_version?: string;
+  agent_features?: Array<{ name: string; enabled: boolean }>;
+  status: ValueOf<AgentPolicyStatus>;
+  package_policies?: PackagePolicy[];
+  agents?: number;
+}
+
+export interface AgentSOAttributes {
+  type: AgentType;
+  active: boolean;
+  enrolled_at: string;
+  user_provided_metadata: AgentMetadata;
+  local_metadata: AgentMetadata;
+  unenrolled_at?: string;
+  unenrollment_started_at?: string;
+  upgraded_at?: string | null;
+  upgrade_started_at?: string | null;
+  access_api_key_id?: string;
+  default_api_key?: string;
+  default_api_key_id?: string;
+  policy_id?: string;
+  policy_revision?: number | null;
+  last_checkin?: string;
+  last_checkin_status?: 'error' | 'online' | 'degraded' | 'updating';
+  last_checkin_message?: string;
+  tags?: string[];
+  components?: FleetServerAgentComponent[];
+  packages?: string[];
+}
+
+export interface FleetProxySOAttributes {
+  name: string;
+  url: string;
+  is_preconfigured: boolean;
+  certificate_authorities?: string | null;
+  certificate?: string | null;
+  certificate_key?: string | null;
+  proxy_headers?: string | null;
+}
+
+export interface FleetServerHostSOAttributes {
+  name: string;
+  host_urls: string[];
+  is_default: boolean;
+  is_preconfigured: boolean;
+  proxy_id?: string | null;
+}
+
+export interface PackagePolicySOAttributes {
+  name: string;
+  namespace: string;
+  enabled: boolean;
+  revision: number;
+  created_at: string;
+  created_by: string;
+  inputs: PackagePolicyInput[];
+  policy_id: string;
+  updated_at: string;
+  updated_by: string;
+  description?: string;
+  is_managed?: boolean;
+  secret_references?: PolicySecretReference[];
+  package?: PackagePolicyPackage;
+  vars?: PackagePolicyConfigRecord;
+  elasticsearch?: {
+    privileges?: {
+      cluster?: string[];
+    };
+  };
+  agents?: number;
+}
+
+export interface OutputSOAttributes {
+  is_default: boolean;
+  is_default_monitoring: boolean;
+  name: string;
+  type: ValueOf<OutputType>;
+  hosts?: string[];
+  ca_sha256?: string | null;
+  ca_trusted_fingerprint?: string | null;
+  is_preconfigured?: boolean;
+  config_yaml?: string | null;
+  proxy_id?: string | null;
+  shipper?: ShipperOutput | null;
+  allow_edit?: string[];
+  output_id?: string;
+  ssl?: string | null; // encrypted ssl field
+}
+
+export interface SettingsSOAttributes {
+  has_seen_add_data_notice?: boolean;
+  fleet_server_hosts?: string[];
+  prerelease_integrations_enabled: boolean;
+}