diff --git a/ts/RemoteConfig.ts b/ts/RemoteConfig.ts
index a3e3387ae..345a83285 100644
--- a/ts/RemoteConfig.ts
+++ b/ts/RemoteConfig.ts
@@ -27,6 +27,8 @@ export type ConfigKeyType =
   | 'desktop.messageCleanup'
   | 'desktop.messageRequests'
   | 'desktop.pnp'
+  | 'desktop.safetyNumberUUID'
+  | 'desktop.safetyNumberUUID.timestamp'
   | 'desktop.retryReceiptLifespan'
   | 'desktop.retryRespondMaxAge'
   | 'desktop.senderKey.retry'
diff --git a/ts/state/ducks/safetyNumber.ts b/ts/state/ducks/safetyNumber.ts
index 1884c231c..9eb236b4a 100644
--- a/ts/state/ducks/safetyNumber.ts
+++ b/ts/state/ducks/safetyNumber.ts
@@ -2,6 +2,8 @@
 // SPDX-License-Identifier: AGPL-3.0-only
 
 import type { ReadonlyDeep } from 'type-fest';
+import type { ThunkAction } from 'redux-thunk';
+
 import { generateSecurityNumberBlock } from '../../util/safetyNumber';
 import type { ConversationType } from './conversations';
 import {
@@ -10,6 +12,8 @@ import {
 } from '../../shims/contactVerification';
 import * as log from '../../logging/log';
 import * as Errors from '../../types/errors';
+import type { StateType as RootStateType } from '../reducer';
+import { getSecurityNumberIdentifierType } from '../selectors/items';
 
 export type SafetyNumberContactType = ReadonlyDeep<{
   safetyNumber: string;
@@ -23,83 +27,108 @@ export type SafetyNumberStateType = ReadonlyDeep<{
   };
 }>;
 
-const GENERATE = 'safetyNumber/GENERATE';
 const GENERATE_FULFILLED = 'safetyNumber/GENERATE_FULFILLED';
-const TOGGLE_VERIFIED = 'safetyNumber/TOGGLE_VERIFIED';
 const TOGGLE_VERIFIED_FULFILLED = 'safetyNumber/TOGGLE_VERIFIED_FULFILLED';
 const TOGGLE_VERIFIED_PENDING = 'safetyNumber/TOGGLE_VERIFIED_PENDING';
 
-type GenerateAsyncActionType = ReadonlyDeep<{
-  contact: ConversationType;
-  safetyNumber: string;
-}>;
-
-type GenerateActionType = ReadonlyDeep<{
-  type: 'safetyNumber/GENERATE';
-  payload: Promise<GenerateAsyncActionType>;
-}>;
-
 type GenerateFulfilledActionType = ReadonlyDeep<{
   type: 'safetyNumber/GENERATE_FULFILLED';
-  payload: GenerateAsyncActionType;
-}>;
-
-type ToggleVerifiedAsyncActionType = ReadonlyDeep<{
-  contact: ConversationType;
-  safetyNumber?: string;
-  safetyNumberChanged?: boolean;
-}>;
-
-type ToggleVerifiedActionType = ReadonlyDeep<{
-  type: 'safetyNumber/TOGGLE_VERIFIED';
   payload: {
-    data: { contact: ConversationType };
-    promise: Promise<ToggleVerifiedAsyncActionType>;
+    contact: ConversationType;
+    safetyNumber: string;
   };
 }>;
 
 type ToggleVerifiedPendingActionType = ReadonlyDeep<{
   type: 'safetyNumber/TOGGLE_VERIFIED_PENDING';
-  payload: ToggleVerifiedAsyncActionType;
+  payload: {
+    contact: ConversationType;
+  };
 }>;
 
 type ToggleVerifiedFulfilledActionType = ReadonlyDeep<{
   type: 'safetyNumber/TOGGLE_VERIFIED_FULFILLED';
-  payload: ToggleVerifiedAsyncActionType;
+  payload: {
+    contact: ConversationType;
+    safetyNumber?: string;
+    safetyNumberChanged?: boolean;
+  };
 }>;
 
 export type SafetyNumberActionType = ReadonlyDeep<
-  | GenerateActionType
   | GenerateFulfilledActionType
-  | ToggleVerifiedActionType
   | ToggleVerifiedPendingActionType
   | ToggleVerifiedFulfilledActionType
 >;
 
-function generate(contact: ConversationType): GenerateActionType {
-  return {
-    type: GENERATE,
-    payload: doGenerate(contact),
-  };
-}
-
-async function doGenerate(
+function generate(
   contact: ConversationType
-): Promise<GenerateAsyncActionType> {
-  const securityNumberBlock = await generateSecurityNumberBlock(contact);
-  return {
-    contact,
-    safetyNumber: securityNumberBlock.join(' '),
+): ThunkAction<void, RootStateType, unknown, GenerateFulfilledActionType> {
+  return async (dispatch, getState) => {
+    try {
+      const securityNumberBlock = await generateSecurityNumberBlock(
+        contact,
+        getSecurityNumberIdentifierType(getState(), { now: Date.now() })
+      );
+      dispatch({
+        type: GENERATE_FULFILLED,
+        payload: {
+          contact,
+          safetyNumber: securityNumberBlock.join(' '),
+        },
+      });
+    } catch (error) {
+      log.error(
+        'failed to generate security number:',
+        Errors.toLogFormat(error)
+      );
+    }
   };
 }
 
-function toggleVerified(contact: ConversationType): ToggleVerifiedActionType {
-  return {
-    type: TOGGLE_VERIFIED,
-    payload: {
-      data: { contact },
-      promise: doToggleVerified(contact),
-    },
+function toggleVerified(
+  contact: ConversationType
+): ThunkAction<
+  void,
+  RootStateType,
+  unknown,
+  ToggleVerifiedPendingActionType | ToggleVerifiedFulfilledActionType
+> {
+  return async (dispatch, getState) => {
+    dispatch({
+      type: TOGGLE_VERIFIED_PENDING,
+      payload: {
+        contact,
+      },
+    });
+
+    try {
+      await alterVerification(contact);
+
+      dispatch({
+        type: TOGGLE_VERIFIED_FULFILLED,
+        payload: {
+          contact,
+        },
+      });
+    } catch (err) {
+      if (err.name === 'OutgoingIdentityKeyError') {
+        await reloadProfiles(contact.id);
+        const securityNumberBlock = await generateSecurityNumberBlock(
+          contact,
+          getSecurityNumberIdentifierType(getState(), { now: Date.now() })
+        );
+
+        dispatch({
+          type: TOGGLE_VERIFIED_FULFILLED,
+          payload: {
+            contact,
+            safetyNumber: securityNumberBlock.join(' '),
+            safetyNumberChanged: true,
+          },
+        });
+      }
+    }
   };
 }
 
@@ -128,27 +157,6 @@ async function alterVerification(contact: ConversationType): Promise<void> {
   }
 }
 
-async function doToggleVerified(
-  contact: ConversationType
-): Promise<ToggleVerifiedAsyncActionType> {
-  try {
-    await alterVerification(contact);
-  } catch (err) {
-    if (err.name === 'OutgoingIdentityKeyError') {
-      await reloadProfiles(contact.id);
-      const securityNumberBlock = await generateSecurityNumberBlock(contact);
-
-      return {
-        contact,
-        safetyNumber: securityNumberBlock.join(' '),
-        safetyNumberChanged: true,
-      };
-    }
-  }
-
-  return { contact };
-}
-
 export const actions = {
   generateSafetyNumber: generate,
   toggleVerified,
diff --git a/ts/state/selectors/items.ts b/ts/state/selectors/items.ts
index ba65c2e1f..7f9592391 100644
--- a/ts/state/selectors/items.ts
+++ b/ts/state/selectors/items.ts
@@ -5,6 +5,7 @@ import { createSelector } from 'reselect';
 import { isInteger } from 'lodash';
 
 import { ITEM_NAME as UNIVERSAL_EXPIRE_TIMER_ITEM } from '../../util/universalExpireTimer';
+import { SecurityNumberIdentifierType } from '../../util/safetyNumber';
 import { innerIsBucketValueEnabled } from '../../RemoteConfig';
 import type { ConfigKeyType, ConfigMapType } from '../../RemoteConfig';
 import type { StateType } from '../reducer';
@@ -145,6 +146,25 @@ export const getContactManagementEnabled = createSelector(
   }
 );
 
+export const getSecurityNumberIdentifierType = createSelector(
+  getRemoteConfig,
+  (_state: StateType, { now }: { now: number }) => now,
+  (remoteConfig: ConfigMapType, now: number): SecurityNumberIdentifierType => {
+    if (isRemoteConfigFlagEnabled(remoteConfig, 'desktop.safetyNumberUUID')) {
+      return SecurityNumberIdentifierType.UUIDIdentifier;
+    }
+
+    const timestamp = remoteConfig['desktop.safetyNumberUUID.timestamp']?.value;
+    if (typeof timestamp !== 'number') {
+      return SecurityNumberIdentifierType.E164Identifier;
+    }
+
+    return now >= timestamp
+      ? SecurityNumberIdentifierType.UUIDIdentifier
+      : SecurityNumberIdentifierType.E164Identifier;
+  }
+);
+
 export const getDefaultConversationColor = createSelector(
   getItems,
   (
diff --git a/ts/util/index.ts b/ts/util/index.ts
index 2343ec19a..fd324ac5f 100644
--- a/ts/util/index.ts
+++ b/ts/util/index.ts
@@ -9,7 +9,6 @@ import { createBatcher } from './batcher';
 import { createWaitBatcher } from './waitBatcher';
 import { deleteForEveryone } from './deleteForEveryone';
 import { downloadAttachment } from './downloadAttachment';
-import { generateSecurityNumber } from './safetyNumber';
 import { getStringForProfileChange } from './getStringForProfileChange';
 import { getTextWithMentions } from './getTextWithMentions';
 import { getUuidsForE164s } from './getUuidsForE164s';
@@ -53,7 +52,6 @@ export {
   downloadAttachment,
   flushMessageCounter,
   fromWebSafeBase64,
-  generateSecurityNumber,
   getStringForProfileChange,
   getTextWithMentions,
   getUserAgent,
diff --git a/ts/util/safetyNumber.ts b/ts/util/safetyNumber.ts
index 39b02016f..6291f86e3 100644
--- a/ts/util/safetyNumber.ts
+++ b/ts/util/safetyNumber.ts
@@ -6,17 +6,18 @@ import type { ConversationType } from '../state/ducks/conversations';
 import { UUID } from '../types/UUID';
 
 import { assertDev } from './assert';
+import { missingCaseError } from './missingCaseError';
 import * as log from '../logging/log';
 
-export async function generateSecurityNumber(
-  ourNumber: string,
+function generateSecurityNumber(
+  ourId: string,
   ourKey: Uint8Array,
-  theirNumber: string,
+  theirId: string,
   theirKey: Uint8Array
-): Promise<string> {
-  const ourNumberBuf = Buffer.from(ourNumber);
+): string {
+  const ourNumberBuf = Buffer.from(ourId);
   const ourKeyObj = PublicKey.deserialize(Buffer.from(ourKey));
-  const theirNumberBuf = Buffer.from(theirNumber);
+  const theirNumberBuf = Buffer.from(theirId);
   const theirKeyObj = PublicKey.deserialize(Buffer.from(theirKey));
 
   const fingerprint = Fingerprint.new(
@@ -28,13 +29,21 @@ export async function generateSecurityNumber(
     theirKeyObj
   );
 
-  const fingerprintString = fingerprint.displayableFingerprint().toString();
-  return Promise.resolve(fingerprintString);
+  return fingerprint.displayableFingerprint().toString();
+}
+
+export enum SecurityNumberIdentifierType {
+  UUIDIdentifier = 'UUIDIdentifier',
+  E164Identifier = 'E164Identifier',
 }
 
 export async function generateSecurityNumberBlock(
-  contact: ConversationType
+  contact: ConversationType,
+  identifierType: SecurityNumberIdentifierType
 ): Promise<Array<string>> {
+  const logId = `generateSecurityNumberBlock(${contact.id}, ${identifierType})`;
+  log.info(`${logId}: starting`);
+
   const { storage } = window.textsecure;
   const ourNumber = storage.user.getNumber();
   const ourUuid = storage.user.getCheckedUuid();
@@ -56,20 +65,33 @@ export async function generateSecurityNumberBlock(
     throw new Error('Could not load their key');
   }
 
-  if (!contact.e164) {
-    log.error(
-      'generateSecurityNumberBlock: Attempted to generate security number for contact with no e164'
-    );
-    return [];
-  }
+  let securityNumber: string;
+  if (identifierType === SecurityNumberIdentifierType.E164Identifier) {
+    if (!contact.e164) {
+      log.error(
+        `${logId}: Attempted to generate security number for contact with no e164`
+      );
+      return [];
+    }
 
-  assertDev(ourNumber, 'Should have our number');
-  const securityNumber = await generateSecurityNumber(
-    ourNumber,
-    ourKey,
-    contact.e164,
-    theirKey
-  );
+    assertDev(ourNumber, 'Should have our number');
+    securityNumber = generateSecurityNumber(
+      ourNumber,
+      ourKey,
+      contact.e164,
+      theirKey
+    );
+  } else if (identifierType === SecurityNumberIdentifierType.UUIDIdentifier) {
+    assertDev(theirUuid, 'Should have their uuid');
+    securityNumber = generateSecurityNumber(
+      ourUuid.toString(),
+      ourKey,
+      theirUuid.toString(),
+      theirKey
+    );
+  } else {
+    throw missingCaseError(identifierType);
+  }
 
   const chunks = [];
   for (let i = 0; i < securityNumber.length; i += 5) {