diff --git a/packages/commerce-sdk-react/src/auth/index.test.ts b/packages/commerce-sdk-react/src/auth/index.test.ts
index b16faf33a1..cdfce86201 100644
--- a/packages/commerce-sdk-react/src/auth/index.test.ts
+++ b/packages/commerce-sdk-react/src/auth/index.test.ts
@@ -190,11 +190,52 @@ describe('Auth', () => {
         expect(auth.ready()).resolves.toEqual(result)
     })
     test('ready - use `fetchedToken` and short circuit network request', async () => {
-        const auth = new Auth({...config, fetchedToken: 'fake-token'})
+        const fetchedToken = jwt.sign(
+            {
+                sub: `cc-slas::zzrf_001::scid:xxxxxx::usid:usid`,
+                isb: `uido:ecom::upn:test@gmail.com::uidn:firstname lastname::gcid:guestuserid::rcid:rcid::chid:siteId`
+            },
+            'secret'
+        )
+        const auth = new Auth({...config, fetchedToken})
         jest.spyOn(auth, 'queueRequest')
-        await auth.ready().then(() => {
-            expect(auth.queueRequest).not.toHaveBeenCalled()
-        })
+        await auth.ready()
+        expect(auth.queueRequest).not.toHaveBeenCalled()
+    })
+    test('ready - use `fetchedToken` and auth data is populated for registered user', async () => {
+        const usid = 'usidddddd'
+        const customerId = 'customerIddddddd'
+        const fetchedToken = jwt.sign(
+            {
+                sub: `cc-slas::zzrf_001::scid:xxxxxx::usid:${usid}`,
+                isb: `uido:ecom::upn:test@gmail.com::uidn:firstname lastname::gcid:guestuserid::rcid:${customerId}::chid:siteId`
+            },
+            'secret'
+        )
+        const auth = new Auth({...config, fetchedToken})
+        await auth.ready()
+        expect(auth.get('access_token')).toBe(fetchedToken)
+        expect(auth.get('customer_id')).toBe(customerId)
+        expect(auth.get('usid')).toBe(usid)
+        expect(auth.get('customer_type')).toBe('registered')
+    })
+    test('ready - use `fetchedToken` and auth data is populated for guest user', async () => {
+        // isb: `uido:slas::upn:Guest::uidn:Guest User::gcid:bclrdGlbIZlHaRxHsZlWYYxHwZ::chid: `
+        const usid = 'usidddddd'
+        const customerId = 'customerIddddddd'
+        const fetchedToken = jwt.sign(
+            {
+                sub: `cc-slas::zzrf_001::scid:xxxxxx::usid:${usid}`,
+                isb: `uido:ecom::upn:Guest::uidn:firstname lastname::gcid:${customerId}::rcid:registeredCid::chid:siteId`
+            },
+            'secret'
+        )
+        const auth = new Auth({...config, fetchedToken})
+        await auth.ready()
+        expect(auth.get('access_token')).toBe(fetchedToken)
+        expect(auth.get('customer_id')).toBe(customerId)
+        expect(auth.get('usid')).toBe(usid)
+        expect(auth.get('customer_type')).toBe('guest')
     })
     test('ready - use refresh token when access token is expired', async () => {
         const auth = new Auth(config)
@@ -220,34 +261,29 @@ describe('Auth', () => {
             auth.set(key, data[key])
         })
 
-        await auth.ready().then(() => {
-            expect(helpers.refreshAccessToken).toBeCalled()
-        })
+        await auth.ready()
+        expect(helpers.refreshAccessToken).toBeCalled()
     })
     test('ready - PKCE flow', async () => {
         const auth = new Auth(config)
 
-        await auth.ready().then(() => {
-            expect(helpers.loginGuestUser).toBeCalled()
-        })
+        await auth.ready()
+        expect(helpers.loginGuestUser).toBeCalled()
     })
     test('loginGuestUser', async () => {
         const auth = new Auth(config)
-        await auth.loginGuestUser().then(() => {
-            expect(helpers.loginGuestUser).toBeCalled()
-        })
+        await auth.loginGuestUser()
+        expect(helpers.loginGuestUser).toBeCalled()
     })
     test('loginRegisteredUserB2C', async () => {
         const auth = new Auth(config)
-        await auth.loginRegisteredUserB2C({username: 'test', password: 'test'}).then(() => {
-            expect(helpers.loginRegisteredUserB2C).toBeCalled()
-        })
+        await auth.loginRegisteredUserB2C({username: 'test', password: 'test'})
+        expect(helpers.loginRegisteredUserB2C).toBeCalled()
     })
     test('logout', async () => {
         const auth = new Auth(config)
-        await auth.logout().then(() => {
-            expect(helpers.loginGuestUser).toBeCalled()
-        })
+        await auth.logout()
+        expect(helpers.loginGuestUser).toBeCalled()
     })
     test('running on the server uses a shared context memory store', async () => {
         const refreshTokenGuest = 'guest'
diff --git a/packages/commerce-sdk-react/src/auth/index.ts b/packages/commerce-sdk-react/src/auth/index.ts
index ad38c783a7..1cf1719751 100644
--- a/packages/commerce-sdk-react/src/auth/index.ts
+++ b/packages/commerce-sdk-react/src/auth/index.ts
@@ -11,7 +11,7 @@ import {
     ShopperLoginTypes,
     ShopperCustomersTypes
 } from 'commerce-sdk-isomorphic'
-import jwtDecode from 'jwt-decode'
+import jwtDecode, {JwtPayload} from 'jwt-decode'
 import {ApiClientConfigParams, Prettify, RemoveStringIndex} from '../hooks/types'
 import {BaseStorage, LocalStorage, CookieStorage, MemoryStorage, StorageType} from './storage'
 import {CustomerType} from '../hooks/useCustomerType'
@@ -31,6 +31,11 @@ interface JWTHeaders {
     iat: number
 }
 
+interface SlasJwtPayload extends JwtPayload {
+    sub: string
+    isb: string
+}
+
 /**
  * The extended field is not from api response, we manually store the auth type,
  * so we don't need to make another API call when we already have the data.
@@ -288,7 +293,12 @@ class Auth {
      */
     async ready() {
         if (this.fetchedToken && this.fetchedToken !== '') {
-            this.pendingToken = Promise.resolve({...this.data, access_token: this.fetchedToken})
+            const {isGuest, customerId, usid} = this.parseSlasJWT(this.fetchedToken)
+            this.set('access_token', this.fetchedToken)
+            this.set('customer_id', customerId)
+            this.set('usid', usid)
+            this.set('customer_type', isGuest ? 'guest' : 'registered')
+            this.pendingToken = Promise.resolve(this.data)
             return this.pendingToken
         }
         if (this.pendingToken) {
@@ -405,6 +415,30 @@ class Auth {
         this.clearStorage()
         return this.loginGuestUser()
     }
+
+    /**
+     * Decode SLAS JWT and extract information such as customer id, usid, etc.
+     *
+     */
+    parseSlasJWT(jwt: string) {
+        const payload = jwtDecode(jwt) as SlasJwtPayload
+        const {sub, isb} = payload
+        // ISB format
+        // 'uido:ecom::upn:Guest||xxxEmailxxx::uidn:FirstName LastName::gcid:xxxGuestCustomerIdxxx::rcid:xxxRegisteredCustomerIdxxx::chid:xxxSiteIdxxx',
+        const isbParts = isb.split('::')
+        const isGuest = isbParts[1] === 'upn:Guest'
+        const customerId = isGuest
+            ? isbParts[3].replace('gcid:', '')
+            : isbParts[4].replace('rcid:', '')
+        // SUB format
+        // cc-slas::zzrf_001::scid:c9c45bfd-0ed3-4aa2-xxxx-40f88962b836::usid:b4865233-de92-4039-xxxx-aa2dfc8c1ea5
+        const usid = sub.split('::')[3].replace('usid:', '')
+        return {
+            isGuest,
+            customerId,
+            usid
+        }
+    }
 }
 
 export default Auth