diff --git a/backend/LexBoxApi/GraphQL/ProjectMutations.cs b/backend/LexBoxApi/GraphQL/ProjectMutations.cs
index 8d4070514..a48d7fa8c 100644
--- a/backend/LexBoxApi/GraphQL/ProjectMutations.cs
+++ b/backend/LexBoxApi/GraphQL/ProjectMutations.cs
@@ -230,6 +230,7 @@ await dbContext.ProjectUsers
     [Error<DbError>]
     [Error<ProjectMembersMustBeVerified>]
     [Error<ProjectMembersMustBeVerifiedForRole>]
+    [Error<ProjectHasNoManagers>]
     [UseMutationConvention]
     [UseFirstOrDefault]
     [UseProjection]
@@ -254,11 +255,14 @@ public async Task<IQueryable<Project>> AskToJoinProject(
         NotFoundException.ThrowIfNull(project);
 
         var managers = project.Users.Where(u => u.Role == ProjectRole.Manager);
+        var emailsSent = 0;
         foreach (var manager in managers)
         {
             if (manager.User is null) continue;
             await emailService.SendJoinProjectRequestEmail(manager.User, user, project);
+            emailsSent++;
         }
+        if (emailsSent == 0) throw new ProjectHasNoManagers(project.Code);
         return dbContext.Projects.Where(p => p.Id == projectId);
     }
 
diff --git a/backend/LexCore/Exceptions/ProjectHasNoManagers.cs b/backend/LexCore/Exceptions/ProjectHasNoManagers.cs
new file mode 100644
index 000000000..4df5f2cb6
--- /dev/null
+++ b/backend/LexCore/Exceptions/ProjectHasNoManagers.cs
@@ -0,0 +1,3 @@
+namespace LexCore.Exceptions;
+
+public class ProjectHasNoManagers(string projectCode) : Exception($"project {projectCode} has no managers");
diff --git a/frontend/schema.graphql b/frontend/schema.graphql
index c090efba6..2476dcf57 100644
--- a/frontend/schema.graphql
+++ b/frontend/schema.graphql
@@ -404,6 +404,10 @@ type ProjectCreatorsMustHaveEmail implements Error {
   message: String!
 }
 
+type ProjectHasNoManagers implements Error {
+  message: String!
+}
+
 type ProjectMemberInvitedByEmail implements Error {
   message: String!
 }
@@ -579,7 +583,7 @@ union AddProjectToOrgError = DbError | NotFoundError
 
 union AddProjectsToOrgError = DbError | NotFoundError
 
-union AskToJoinProjectError = NotFoundError | DbError | ProjectMembersMustBeVerified | ProjectMembersMustBeVerifiedForRole
+union AskToJoinProjectError = NotFoundError | DbError | ProjectMembersMustBeVerified | ProjectMembersMustBeVerifiedForRole | ProjectHasNoManagers
 
 union BulkAddOrgMembersError = NotFoundError | DbError | UnauthorizedAccessError
 
diff --git a/frontend/src/lib/i18n/locales/en.json b/frontend/src/lib/i18n/locales/en.json
index 552e726f2..be14d0e7d 100644
--- a/frontend/src/lib/i18n/locales/en.json
+++ b/frontend/src/lib/i18n/locales/en.json
@@ -212,6 +212,7 @@ Lexbox is free and [open source](https://github.com/sillsdev/languageforge-lexbo
       "no_thanks": "No thanks, create a new project",
       "click_to_view_related_projects": "Found {count, plural, one {# related project} other {# related projects}}, click here to see {count, plural, one {it} other {them}}",
       "join_request_sent": "Your request to join the {projectName} project has been sent to the project manager(s)",
+      "join_request_error_no_managers": "The {projectName} project has no project managers, so your request to join could not be sent",
       "description": "Description",
       "no_description": "This project does not have a description",
       "name_missing": "Project name required",
@@ -531,6 +532,9 @@ Lexbox is free and [open source](https://github.com/sillsdev/languageforge-lexbo
     "promote_project": {
       "label": "Promote to real project",
     },
+    "join_project": {
+      "label": "Ask to join project",
+    },
     "open_with_viewer": "Browse",
     "open_with_flex": {
       "button": "Open with FLEx",
diff --git a/frontend/src/routes/(authenticated)/project/[project_code]/+page.svelte b/frontend/src/routes/(authenticated)/project/[project_code]/+page.svelte
index f7e3ff574..f990c18ec 100644
--- a/frontend/src/routes/(authenticated)/project/[project_code]/+page.svelte
+++ b/frontend/src/routes/(authenticated)/project/[project_code]/+page.svelte
@@ -56,6 +56,8 @@
   import { getSearchParamValues } from '$lib/util/query-params';
   import FlexModelVersionText from '$lib/components/Projects/FlexModelVersionText.svelte';
   import CrdtSyncButton from './CrdtSyncButton.svelte';
+  import {_askToJoinProject} from '../create/+page'; // TODO: Should we duplicate this function in the project_code/+page.ts file, rather than importing it from elsewhere?
+  import {Duration} from '$lib/util/time';
 
   export let data: PageData;
   $: user = data.user;
@@ -143,6 +145,11 @@
     || projectRole && !project.isConfidential // public by default for members (non-members shouldn't even be here)
     || orgRoles.some(role => role === OrgRole.Admin);
 
+  // Almost mirrors PermissionService.CanAskToJoinProject() in C#, but admins won't be shown the "ask to join" button
+  $: canAskToJoinProject = !user.isAdmin
+    && !projectRole
+    && orgRoles.some((_) => true);
+
   let resetProjectModal: ResetProjectModal;
   async function resetProject(): Promise<void> {
     await resetProjectModal.open(project.code, project.resetStatus);
@@ -271,6 +278,19 @@
     }
   }
 
+  let askLoading = false;
+  async function askToJoinProject(projectId: string, projectName: string): Promise<void> {
+    askLoading = true;
+    const joinResult = await _askToJoinProject(projectId);
+    askLoading = false;
+    if (!joinResult.error) {
+      notifySuccess($t('project.create.join_request_sent', { projectName }), Duration.Persistent);
+    }
+    if (joinResult.error?.byType('ProjectHasNoManagers')) {
+      notifyWarning($t('project.create.join_request_error_no_managers', { projectName }), Duration.Persistent);
+    }
+  }
+
   let projectConfidentialityModal: ProjectConfidentialityModal;
   let openInFlexModal: OpenInFlexModal;
   let leaveModal: ConfirmModal;
@@ -316,6 +336,17 @@
         <CrdtSyncButton projectId={project.id} />
         <OpenInFlexModal bind:this={openInFlexModal} {project}/>
         <OpenInFlexButton projectId={project.id} on:click={openInFlexModal.open}/>
+      {:else if canAskToJoinProject}
+        <Button
+          variant="btn-primary"
+          loading={askLoading}
+          on:click={() => askToJoinProject(project.id, project.name)}
+        >
+          {#if !askLoading}
+            <span class="i-mdi-email text-2xl"></span>
+          {/if}
+          {$t('project_page.join_project.label')}
+        </Button>
       {:else}
         <Dropdown>
           <button class="btn btn-primary">
diff --git a/frontend/src/routes/(authenticated)/project/create/+page.ts b/frontend/src/routes/(authenticated)/project/create/+page.ts
index 2733219c0..6d899979d 100644
--- a/frontend/src/routes/(authenticated)/project/create/+page.ts
+++ b/frontend/src/routes/(authenticated)/project/create/+page.ts
@@ -135,6 +135,7 @@ export async function _askToJoinProject(projectId: string): $OpResult<AskToJoinP
             id
           }
           errors {
+            __typename
             ... on DbError {
               code
             }