diff --git a/packages/api/src/Domain/Server/Subscription/SubscriptionServer.spec.ts b/packages/api/src/Domain/Server/Subscription/SubscriptionServer.spec.ts
index 8f235b7cc..6867e0633 100644
--- a/packages/api/src/Domain/Server/Subscription/SubscriptionServer.spec.ts
+++ b/packages/api/src/Domain/Server/Subscription/SubscriptionServer.spec.ts
@@ -38,7 +38,7 @@ describe('SubscriptionServer', () => {
   })
 
   it('should accept an invite to a shared subscription', async () => {
-    httpService.get = jest.fn().mockReturnValue({
+    httpService.post = jest.fn().mockReturnValue({
       data: { success: true },
     } as jest.Mocked<SubscriptionInviteAcceptResponse>)
 
diff --git a/packages/api/src/Domain/Server/Subscription/SubscriptionServer.ts b/packages/api/src/Domain/Server/Subscription/SubscriptionServer.ts
index 23552df0f..23abcf5d7 100644
--- a/packages/api/src/Domain/Server/Subscription/SubscriptionServer.ts
+++ b/packages/api/src/Domain/Server/Subscription/SubscriptionServer.ts
@@ -17,7 +17,7 @@ export class SubscriptionServer implements SubscriptionServerInterface {
   constructor(private httpService: HttpServiceInterface) {}
 
   async acceptInvite(params: SubscriptionInviteAcceptRequestParams): Promise<SubscriptionInviteAcceptResponse> {
-    const response = await this.httpService.get(Paths.v1.acceptInvite(params.inviteUuid), params)
+    const response = await this.httpService.post(Paths.v1.acceptInvite(params.inviteUuid), params)
 
     return response as SubscriptionInviteAcceptResponse
   }
diff --git a/packages/services/src/Domain/Subscription/SubscriptionClientInterface.ts b/packages/services/src/Domain/Subscription/SubscriptionClientInterface.ts
index c01ab70cd..ce9df96d8 100644
--- a/packages/services/src/Domain/Subscription/SubscriptionClientInterface.ts
+++ b/packages/services/src/Domain/Subscription/SubscriptionClientInterface.ts
@@ -5,4 +5,5 @@ export interface SubscriptionClientInterface {
   listSubscriptionInvitations(): Promise<Invitation[]>
   inviteToSubscription(inviteeEmail: string): Promise<boolean>
   cancelInvitation(inviteUuid: Uuid): Promise<boolean>
+  acceptInvitation(inviteUuid: Uuid): Promise<{ success: true } | { success: false; message: string }>
 }
diff --git a/packages/services/src/Domain/Subscription/SubscriptionManager.spec.ts b/packages/services/src/Domain/Subscription/SubscriptionManager.spec.ts
index 302a1c6b2..568e0cdd7 100644
--- a/packages/services/src/Domain/Subscription/SubscriptionManager.spec.ts
+++ b/packages/services/src/Domain/Subscription/SubscriptionManager.spec.ts
@@ -12,6 +12,7 @@ describe('SubscriptionManager', () => {
   beforeEach(() => {
     subscriptionApiService = {} as jest.Mocked<SubscriptionApiServiceInterface>
     subscriptionApiService.cancelInvite = jest.fn()
+    subscriptionApiService.acceptInvite = jest.fn()
     subscriptionApiService.invite = jest.fn()
     subscriptionApiService.listInvites = jest.fn()
 
@@ -80,4 +81,27 @@ describe('SubscriptionManager', () => {
 
     expect(await createManager().listSubscriptionInvitations()).toEqual([])
   })
+
+  it('should accept invite to a shared subscription', async () => {
+    subscriptionApiService.acceptInvite = jest.fn().mockReturnValue({ data: { success: true } })
+
+    expect(await createManager().acceptInvitation('1-2-3')).toEqual({ success: true })
+  })
+
+  it('should not accept invite if the api fails to do so', async () => {
+    subscriptionApiService.acceptInvite = jest.fn().mockReturnValue({ data: { error: { message: 'foobar' } } })
+
+    expect(await createManager().acceptInvitation('1-2-3')).toEqual({ success: false, message: 'foobar' })
+  })
+
+  it('should not accept invite if the api throws an error', async () => {
+    subscriptionApiService.acceptInvite = jest.fn().mockImplementation(() => {
+      throw new Error('Oops')
+    })
+
+    expect(await createManager().acceptInvitation('1-2-3')).toEqual({
+      success: false,
+      message: 'Could not accept invitation.',
+    })
+  })
 })
diff --git a/packages/services/src/Domain/Subscription/SubscriptionManager.ts b/packages/services/src/Domain/Subscription/SubscriptionManager.ts
index e3742d55d..a98bc082b 100644
--- a/packages/services/src/Domain/Subscription/SubscriptionManager.ts
+++ b/packages/services/src/Domain/Subscription/SubscriptionManager.ts
@@ -13,6 +13,20 @@ export class SubscriptionManager extends AbstractService implements Subscription
     super(internalEventBus)
   }
 
+  async acceptInvitation(inviteUuid: string): Promise<{ success: true } | { success: false; message: string }> {
+    try {
+      const result = await this.subscriptionApiService.acceptInvite(inviteUuid)
+
+      if (result.data.error) {
+        return { success: false, message: result.data.error.message }
+      }
+
+      return result.data
+    } catch (error) {
+      return { success: false, message: 'Could not accept invitation.' }
+    }
+  }
+
   async listSubscriptionInvitations(): Promise<Invitation[]> {
     try {
       const response = await this.subscriptionApiService.listInvites()
diff --git a/packages/ui-services/src/Route/RouteService.ts b/packages/ui-services/src/Route/RouteService.ts
index 3c4492044..652b7c8c3 100644
--- a/packages/ui-services/src/Route/RouteService.ts
+++ b/packages/ui-services/src/Route/RouteService.ts
@@ -5,6 +5,7 @@ import {
   InternalEventBusInterface,
 } from '@standardnotes/services'
 
+import { RootQueryParam } from './RootQueryParam'
 import { RouteParser } from './RouteParser'
 import { RouteParserInterface } from './RouteParserInterface'
 import { RouteServiceEvent } from './RouteServiceEvent'
@@ -30,13 +31,13 @@ export class RouteService
     this.unsubApp()
   }
 
-  public getRoute(): RouteParserInterface {
+  getRoute(): RouteParserInterface {
     return new RouteParser(window.location.href)
   }
 
-  public removeSettingsFromURLQueryParameters() {
+  removeQueryParameterFromURL(param: RootQueryParam): void {
     const urlSearchParams = new URLSearchParams(window.location.search)
-    urlSearchParams.delete('settings')
+    urlSearchParams.delete(param)
 
     const newUrl = `${window.location.origin}${window.location.pathname}${urlSearchParams.toString()}`
     window.history.replaceState(null, document.title, newUrl)
diff --git a/packages/ui-services/src/Route/RouteServiceInterface.ts b/packages/ui-services/src/Route/RouteServiceInterface.ts
index 7a66ff1db..3b6ade3ff 100644
--- a/packages/ui-services/src/Route/RouteServiceInterface.ts
+++ b/packages/ui-services/src/Route/RouteServiceInterface.ts
@@ -1,7 +1,8 @@
+import { RootQueryParam } from './RootQueryParam'
 import { RouteParserInterface } from './RouteParserInterface'
 
 export interface RouteServiceInterface {
   deinit(): void
   getRoute(): RouteParserInterface
-  removeSettingsFromURLQueryParameters(): void
+  removeQueryParameterFromURL(param: RootQueryParam): void
 }
diff --git a/packages/ui-services/src/Toast/ToastService.ts b/packages/ui-services/src/Toast/ToastService.ts
new file mode 100644
index 000000000..20f1e4d87
--- /dev/null
+++ b/packages/ui-services/src/Toast/ToastService.ts
@@ -0,0 +1,12 @@
+import { addToast, ToastType } from '@standardnotes/toast'
+
+import { ToastServiceInterface } from './ToastServiceInterface'
+
+export class ToastService implements ToastServiceInterface {
+  showToast(type: ToastType, message: string): void {
+    addToast({
+      type: type,
+      message,
+    })
+  }
+}
diff --git a/packages/ui-services/src/Toast/ToastServiceInterface.ts b/packages/ui-services/src/Toast/ToastServiceInterface.ts
new file mode 100644
index 000000000..dbdf56464
--- /dev/null
+++ b/packages/ui-services/src/Toast/ToastServiceInterface.ts
@@ -0,0 +1,5 @@
+import { ToastType } from '@standardnotes/toast'
+
+export interface ToastServiceInterface {
+  showToast(type: ToastType, message: string): void
+}
diff --git a/packages/ui-services/src/index.ts b/packages/ui-services/src/index.ts
index 5202f2d9f..034127bab 100644
--- a/packages/ui-services/src/index.ts
+++ b/packages/ui-services/src/index.ts
@@ -8,7 +8,9 @@ export * from './Route/Params/OnboardingParams'
 export * from './Route/Params/PurchaseParams'
 export * from './Route/Params/SettingsParams'
 export * from './Route/Params/SubscriptionInviteParams'
+export * from './Route/RootQueryParam'
 export * from './Route/RouteParser'
+export * from './Route/RouteParserInterface'
 export * from './Route/RouteType'
 export * from './Route/RouteService'
 export * from './Route/RouteServiceInterface'
@@ -16,3 +18,5 @@ export * from './Route/RouteServiceEvent'
 export * from './Security/AutolockService'
 export * from './Storage/LocalStorage'
 export * from './Theme/ThemeManager'
+export * from './Toast/ToastService'
+export * from './Toast/ToastServiceInterface'
diff --git a/packages/web/src/javascripts/Controllers/PreferencesController.ts b/packages/web/src/javascripts/Controllers/PreferencesController.ts
index 187c779e6..4e0c823ac 100644
--- a/packages/web/src/javascripts/Controllers/PreferencesController.ts
+++ b/packages/web/src/javascripts/Controllers/PreferencesController.ts
@@ -1,6 +1,6 @@
 import { InternalEventBus } from '@standardnotes/snjs'
 import { action, computed, makeObservable, observable } from 'mobx'
-import { PreferenceId } from '@standardnotes/ui-services'
+import { PreferenceId, RootQueryParam } from '@standardnotes/ui-services'
 import { AbstractViewController } from './Abstract/AbstractViewController'
 import { WebApplication } from '@/Application/Application'
 
@@ -34,7 +34,7 @@ export class PreferencesController extends AbstractViewController {
   closePreferences = (): void => {
     this._open = false
     this.currentPane = DEFAULT_PANE
-    this.application.routeService.removeSettingsFromURLQueryParameters()
+    this.application.routeService.removeQueryParameterFromURL(RootQueryParam.Settings)
   }
 
   get isOpen(): boolean {
diff --git a/packages/web/src/javascripts/Controllers/ViewControllerManager.ts b/packages/web/src/javascripts/Controllers/ViewControllerManager.ts
index 214bc8816..b7381bad0 100644
--- a/packages/web/src/javascripts/Controllers/ViewControllerManager.ts
+++ b/packages/web/src/javascripts/Controllers/ViewControllerManager.ts
@@ -1,5 +1,5 @@
 import { PaneController } from './PaneController'
-import { storage, StorageKey } from '@standardnotes/ui-services'
+import { storage, StorageKey, ToastService, ToastServiceInterface } from '@standardnotes/ui-services'
 import { WebApplication } from '@/Application/Application'
 import { AccountMenuController } from '@/Controllers/AccountMenu/AccountMenuController'
 import { destroyAllObjectProperties } from '@/Utils'
@@ -71,6 +71,7 @@ export class ViewControllerManager implements InternalEventHandlerInterface {
   private subscriptionManager: SubscriptionClientInterface
   private persistenceService: PersistenceService
   private applicationEventObserver: EventObserverInterface
+  private toastService: ToastServiceInterface
 
   constructor(public application: WebApplication, private device: WebOrDesktopDeviceInterface) {
     this.eventBus = new InternalEventBus()
@@ -146,6 +147,8 @@ export class ViewControllerManager implements InternalEventHandlerInterface {
 
     this.historyModalController = new HistoryModalController(this.application, this.eventBus)
 
+    this.toastService = new ToastService()
+
     this.applicationEventObserver = new ApplicationEventObserver(
       application.routeService,
       this.purchaseFlowController,
@@ -154,6 +157,8 @@ export class ViewControllerManager implements InternalEventHandlerInterface {
       this.syncStatusController,
       application.sync,
       application.sessions,
+      application.subscriptions,
+      this.toastService,
     )
 
     this.addAppEventObserver()
diff --git a/packages/web/src/javascripts/Event/ApplicationEventObserver.spec.ts b/packages/web/src/javascripts/Event/ApplicationEventObserver.spec.ts
index cd0c3e3ca..a61d31e09 100644
--- a/packages/web/src/javascripts/Event/ApplicationEventObserver.spec.ts
+++ b/packages/web/src/javascripts/Event/ApplicationEventObserver.spec.ts
@@ -2,17 +2,30 @@
  * @jest-environment jsdom
  */
 
-import { RouteServiceInterface, RouteType } from '@standardnotes/ui-services'
-import { ApplicationEvent, SessionsClientInterface, SyncClientInterface, SyncOpStatus, User } from '@standardnotes/snjs'
+import {
+  RootQueryParam,
+  RouteServiceInterface,
+  RouteParserInterface,
+  RouteType,
+  ToastServiceInterface,
+} from '@standardnotes/ui-services'
+import { ToastType } from '@standardnotes/toast'
+import {
+  ApplicationEvent,
+  SessionsClientInterface,
+  SubscriptionClientInterface,
+  SyncClientInterface,
+  SyncOpStatus,
+  User,
+} from '@standardnotes/snjs'
 
 import { AccountMenuController } from '@/Controllers/AccountMenu/AccountMenuController'
 import { PreferencesController } from '@/Controllers/PreferencesController'
 import { PurchaseFlowController } from '@/Controllers/PurchaseFlow/PurchaseFlowController'
 import { SyncStatusController } from '@/Controllers/SyncStatusController'
+import { AccountMenuPane } from '@/Components/AccountMenu/AccountMenuPane'
 
 import { ApplicationEventObserver } from './ApplicationEventObserver'
-import { RouteParserInterface } from '@standardnotes/ui-services/dist/Route/RouteParserInterface'
-import { AccountMenuPane } from '@/Components/AccountMenu/AccountMenuPane'
 
 describe('ApplicationEventObserver', () => {
   let routeService: RouteServiceInterface
@@ -22,6 +35,8 @@ describe('ApplicationEventObserver', () => {
   let syncStatusController: SyncStatusController
   let syncClient: SyncClientInterface
   let sessionManager: SessionsClientInterface
+  let subscriptionManager: SubscriptionClientInterface
+  let toastService: ToastServiceInterface
 
   const createObserver = () =>
     new ApplicationEventObserver(
@@ -32,6 +47,8 @@ describe('ApplicationEventObserver', () => {
       syncStatusController,
       syncClient,
       sessionManager,
+      subscriptionManager,
+      toastService,
     )
 
   beforeEach(() => {
@@ -39,6 +56,7 @@ describe('ApplicationEventObserver', () => {
     routeService.getRoute = jest.fn().mockReturnValue({
       type: RouteType.None,
     } as jest.Mocked<RouteParserInterface>)
+    routeService.removeQueryParameterFromURL = jest.fn()
 
     purchaseFlowController = {} as jest.Mocked<PurchaseFlowController>
     purchaseFlowController.openPurchaseFlow = jest.fn()
@@ -59,6 +77,12 @@ describe('ApplicationEventObserver', () => {
 
     sessionManager = {} as jest.Mocked<SessionsClientInterface>
     sessionManager.getUser = jest.fn().mockReturnValue({} as jest.Mocked<User>)
+
+    subscriptionManager = {} as jest.Mocked<SubscriptionClientInterface>
+    subscriptionManager.acceptInvitation = jest.fn()
+
+    toastService = {} as jest.Mocked<ToastServiceInterface>
+    toastService.showToast = jest.fn()
   })
 
   describe('Upon Application Launched', () => {
@@ -102,6 +126,59 @@ describe('ApplicationEventObserver', () => {
       expect(preferencesController.openPreferences).not.toHaveBeenCalled()
       expect(preferencesController.setCurrentPane).not.toHaveBeenCalled()
     })
+
+    it('should open up sign in if user is not logged in and to accept subscription invitation', async () => {
+      sessionManager.getUser = jest.fn().mockReturnValue(undefined)
+      routeService.getRoute = jest.fn().mockReturnValue({
+        type: RouteType.AcceptSubscriptionInvite,
+        subscriptionInviteParams: {
+          inviteUuid: '1-2-3',
+        },
+      } as jest.Mocked<RouteParserInterface>)
+
+      await createObserver().handle(ApplicationEvent.Launched)
+
+      expect(accountMenuController.setShow).toHaveBeenCalledWith(true)
+      expect(accountMenuController.setCurrentPane).toHaveBeenCalledWith(AccountMenuPane.SignIn)
+      expect(subscriptionManager.acceptInvitation).not.toHaveBeenCalled()
+      expect(toastService.showToast).not.toHaveBeenCalled()
+    })
+
+    it('should accept subscription invitation if user is logged in', async () => {
+      subscriptionManager.acceptInvitation = jest.fn().mockReturnValue({ success: true })
+      routeService.getRoute = jest.fn().mockReturnValue({
+        type: RouteType.AcceptSubscriptionInvite,
+        subscriptionInviteParams: {
+          inviteUuid: '1-2-3',
+        },
+      } as jest.Mocked<RouteParserInterface>)
+
+      await createObserver().handle(ApplicationEvent.Launched)
+
+      expect(subscriptionManager.acceptInvitation).toHaveBeenCalledWith('1-2-3')
+      expect(toastService.showToast).toHaveBeenCalledWith(
+        ToastType.Success,
+        'Successfully joined a shared subscription',
+      )
+      expect(routeService.removeQueryParameterFromURL).toHaveBeenCalledWith(RootQueryParam.AcceptSubscriptionInvite)
+    })
+
+    it('should show accept subscription invitation failure if user is logged in and accepting fails', async () => {
+      subscriptionManager.acceptInvitation = jest.fn().mockReturnValue({ success: false, message: 'Oops!' })
+
+      routeService.getRoute = jest.fn().mockReturnValue({
+        type: RouteType.AcceptSubscriptionInvite,
+        subscriptionInviteParams: {
+          inviteUuid: '1-2-3',
+        },
+      } as jest.Mocked<RouteParserInterface>)
+
+      await createObserver().handle(ApplicationEvent.Launched)
+
+      expect(subscriptionManager.acceptInvitation).toHaveBeenCalledWith('1-2-3')
+      expect(toastService.showToast).toHaveBeenCalledWith(ToastType.Error, 'Oops!')
+      expect(routeService.removeQueryParameterFromURL).toHaveBeenCalledWith(RootQueryParam.AcceptSubscriptionInvite)
+    })
   })
 
   describe('Upon Signing In', () => {
@@ -118,6 +195,25 @@ describe('ApplicationEventObserver', () => {
       expect(preferencesController.openPreferences).toHaveBeenCalled()
       expect(preferencesController.setCurrentPane).toHaveBeenCalledWith('general')
     })
+
+    it('should accept subscription invitation', async () => {
+      subscriptionManager.acceptInvitation = jest.fn().mockReturnValue({ success: true })
+      routeService.getRoute = jest.fn().mockReturnValue({
+        type: RouteType.AcceptSubscriptionInvite,
+        subscriptionInviteParams: {
+          inviteUuid: '1-2-3',
+        },
+      } as jest.Mocked<RouteParserInterface>)
+
+      await createObserver().handle(ApplicationEvent.SignedIn)
+
+      expect(subscriptionManager.acceptInvitation).toHaveBeenCalledWith('1-2-3')
+      expect(toastService.showToast).toHaveBeenCalledWith(
+        ToastType.Success,
+        'Successfully joined a shared subscription',
+      )
+      expect(routeService.removeQueryParameterFromURL).toHaveBeenCalledWith(RootQueryParam.AcceptSubscriptionInvite)
+    })
   })
 
   describe('Upon Sync Status Changing', () => {
diff --git a/packages/web/src/javascripts/Event/ApplicationEventObserver.ts b/packages/web/src/javascripts/Event/ApplicationEventObserver.ts
index dbe7b42be..831604547 100644
--- a/packages/web/src/javascripts/Event/ApplicationEventObserver.ts
+++ b/packages/web/src/javascripts/Event/ApplicationEventObserver.ts
@@ -1,5 +1,11 @@
-import { RouteServiceInterface, RouteType } from '@standardnotes/ui-services'
-import { ApplicationEvent, SessionsClientInterface, SyncClientInterface } from '@standardnotes/snjs'
+import { RootQueryParam, RouteParserInterface, RouteServiceInterface, RouteType, ToastServiceInterface } from '@standardnotes/ui-services'
+import {
+  ApplicationEvent,
+  SessionsClientInterface,
+  SubscriptionClientInterface,
+  SyncClientInterface,
+} from '@standardnotes/snjs'
+import { ToastType } from '@standardnotes/toast'
 
 import { PurchaseFlowController } from '@/Controllers/PurchaseFlow/PurchaseFlowController'
 import { AccountMenuController } from '@/Controllers/AccountMenu/AccountMenuController'
@@ -18,6 +24,8 @@ export class ApplicationEventObserver implements EventObserverInterface {
     private syncStatusController: SyncStatusController,
     private syncClient: SyncClientInterface,
     private sessionManager: SessionsClientInterface,
+    private subscriptionManager: SubscriptionClientInterface,
+    private toastService: ToastServiceInterface,
   ) {}
 
   async handle(event: ApplicationEvent): Promise<void> {
@@ -33,8 +41,7 @@ export class ApplicationEventObserver implements EventObserverInterface {
             case RouteType.Settings: {
               const user = this.sessionManager.getUser()
               if (user === undefined) {
-                this.accountMenuController.setShow(true)
-                this.accountMenuController.setCurrentPane(AccountMenuPane.SignIn)
+                this.promptUserSignIn()
 
                 break
               }
@@ -43,6 +50,17 @@ export class ApplicationEventObserver implements EventObserverInterface {
               this.preferencesController.setCurrentPane(route.settingsParams.panel)
               break
             }
+            case RouteType.AcceptSubscriptionInvite: {
+              const user = this.sessionManager.getUser()
+              if (user === undefined) {
+                this.promptUserSignIn()
+
+                break
+              }
+              await this.acceptSubscriptionInvitation(route)
+
+              break
+            }
           }
         }
         break
@@ -54,6 +72,10 @@ export class ApplicationEventObserver implements EventObserverInterface {
               this.preferencesController.openPreferences()
               this.preferencesController.setCurrentPane(route.settingsParams.panel)
 
+              break
+            case RouteType.AcceptSubscriptionInvite:
+              await this.acceptSubscriptionInvitation(route)
+
               break
           }
         }
@@ -63,4 +85,20 @@ export class ApplicationEventObserver implements EventObserverInterface {
         break
     }
   }
+
+  private promptUserSignIn(): void {
+    this.accountMenuController.setShow(true)
+    this.accountMenuController.setCurrentPane(AccountMenuPane.SignIn)
+  }
+
+  private async acceptSubscriptionInvitation(route: RouteParserInterface): Promise<void> {
+    const acceptResult = await this.subscriptionManager.acceptInvitation(route.subscriptionInviteParams.inviteUuid)
+
+    const toastType = acceptResult.success ? ToastType.Success : ToastType.Error
+    const toastMessage = acceptResult.success ? 'Successfully joined a shared subscription' : acceptResult.message
+
+    this.toastService.showToast(toastType, toastMessage)
+
+    this.routeService.removeQueryParameterFromURL(RootQueryParam.AcceptSubscriptionInvite)
+  }
 }