diff --git a/apps/admin-x-activitypub/package.json b/apps/admin-x-activitypub/package.json
index 0a82021058..a88ecd5c2e 100644
--- a/apps/admin-x-activitypub/package.json
+++ b/apps/admin-x-activitypub/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@tryghost/admin-x-activitypub",
-  "version": "0.3.21",
+  "version": "0.3.22",
   "license": "MIT",
   "repository": {
     "type": "git",
diff --git a/apps/admin-x-activitypub/src/api/activitypub.test.ts b/apps/admin-x-activitypub/src/api/activitypub.test.ts
index f16ec28578..5c64da3623 100644
--- a/apps/admin-x-activitypub/src/api/activitypub.test.ts
+++ b/apps/admin-x-activitypub/src/api/activitypub.test.ts
@@ -1336,4 +1336,33 @@ describe('ActivityPubAPI', function () {
             expect(actual).toEqual(expected);
         });
     });
+
+    describe('note', function () {
+        test('It creates a note and returns it', async function () {
+            const fakeFetch = Fetch({
+                [`https://activitypub.api/.ghost/activitypub/actions/note`]: {
+                    async assert(_resource, init) {
+                        expect(init?.method).toEqual('POST');
+                        expect(init?.body).toEqual('{"content":"Hello, world!"}');
+                    },
+                    response: JSONResponse({
+                        id: 'https://example.com/note/abc123'
+                    })
+                }
+            });
+
+            const api = new ActivityPubAPI(
+                new URL('https://activitypub.api'),
+                new URL('https://auth.api'),
+                'index',
+                fakeFetch
+            );
+
+            const result = await api.note('Hello, world!');
+
+            expect(result).toEqual({
+                id: 'https://example.com/note/abc123'
+            });
+        });
+    });
 });
diff --git a/apps/admin-x-activitypub/src/api/activitypub.ts b/apps/admin-x-activitypub/src/api/activitypub.ts
index ab37d24788..11a31876a1 100644
--- a/apps/admin-x-activitypub/src/api/activitypub.ts
+++ b/apps/admin-x-activitypub/src/api/activitypub.ts
@@ -325,6 +325,12 @@ export class ActivityPubAPI {
         return response;
     }
 
+    async note(content: string) {
+        const url = new URL('.ghost/activitypub/actions/note', this.apiUrl);
+        const response = await this.fetchJSON(url, 'POST', {content});
+        return response;
+    }
+
     get userApiUrl() {
         return new URL(`.ghost/activitypub/users/${this.handle}`, this.apiUrl);
     }
diff --git a/apps/admin-x-activitypub/src/components/Inbox.tsx b/apps/admin-x-activitypub/src/components/Inbox.tsx
index 4437af8233..629af8ddae 100644
--- a/apps/admin-x-activitypub/src/components/Inbox.tsx
+++ b/apps/admin-x-activitypub/src/components/Inbox.tsx
@@ -95,7 +95,7 @@ const Inbox: React.FC<InboxProps> = ({layout}) => {
                                             </div>
                                             <Button aria-label='New post' className='text absolute inset-0 w-full rounded-lg bg-white pl-[64px] text-left text-[1.5rem] tracking-normal text-grey-500 shadow-[0_0_1px_rgba(0,0,0,.32),0_1px_6px_rgba(0,0,0,.03),0_8px_10px_-8px_rgba(0,0,0,.16)] transition-all hover:shadow-[0_0_1px_rgba(0,0,0,.32),0_1px_6px_rgba(0,0,0,.03),0_8px_10px_-8px_rgba(0,0,0,.26)]' label='What&apos;s new?' unstyled onClick={() => NiceModal.show(NewPostModal)} />
                                         </div>}
-                                        <ul className={`mx-auto flex w-full flex-col`}>
+                                        <ul className={`mx-auto flex w-full flex-col ${layout === 'inbox' && 'mt-3'}`}>
                                             {activities.map((activity, index) => (
                                                 <li
                                                     key={activity.id}
diff --git a/apps/admin-x-activitypub/src/components/modals/NewPostModal.tsx b/apps/admin-x-activitypub/src/components/modals/NewPostModal.tsx
index 32ec2d8034..5c1bf04f8a 100644
--- a/apps/admin-x-activitypub/src/components/modals/NewPostModal.tsx
+++ b/apps/admin-x-activitypub/src/components/modals/NewPostModal.tsx
@@ -3,42 +3,76 @@ import APAvatar from '../global/APAvatar';
 import NiceModal, {useModal} from '@ebay/nice-modal-react';
 import {ActorProperties} from '@tryghost/admin-x-framework/api/activitypub';
 import {Modal, showToast} from '@tryghost/admin-x-design-system';
-import {useUserDataForUser} from '../../hooks/useActivityPubQueries';
+import {useNoteMutationForUser, useUserDataForUser} from '../../hooks/useActivityPubQueries';
+import {useState} from 'react';
 
 const NewPostModal = NiceModal.create(() => {
     const modal = useModal();
     const {data: user} = useUserDataForUser('index');
+    const noteMutation = useNoteMutationForUser('index');
+
+    const [content, setContent] = useState('');
+
+    const isDisabled = noteMutation.isLoading || !content.trim();
+
+    const handlePost = async () => {
+        const trimmedContent = content.trim();
+        if (!trimmedContent) {
+            return;
+        }
+
+        await noteMutation.mutate({content: trimmedContent}, {
+            onSuccess() {
+                showToast({
+                    message: 'Note posted',
+                    type: 'success'
+                });
+                modal.remove();
+            },
+            onError() {
+                showToast({
+                    message: 'An error occurred while posting your note.',
+                    type: 'error'
+                });
+            }
+        });
+    };
+
+    const handleCancel = () => {
+        modal.remove();
+    };
+
+    const handleChange = (e: React.ChangeEvent<HTMLTextAreaElement>) => {
+        setContent(e.target.value);
+    };
 
     return (
         <Modal
             cancelLabel="Cancel"
+            okColor="black"
+            okDisabled={isDisabled}
             okLabel="Post"
+            size="md"
             stickyFooter={true}
             width={575}
-            onCancel={() => {
-                modal.remove();
-            }}
-            onOk={() => {
-                showToast({
-                    message: 'Note sent',
-                    type: 'success'
-                });
-                modal.remove();
-            }}
+            onCancel={handleCancel}
+            onOk={handlePost}
         >
             <div className='flex items-start gap-2'>
                 <APAvatar author={user as ActorProperties} />
                 <FormPrimitive.Root asChild>
                     <div className='flex w-full flex-col'>
-                        <FormPrimitive.Field name='temp' asChild>
+                        <FormPrimitive.Field name='content' asChild>
                             <FormPrimitive.Control asChild>
                                 <textarea
                                     autoFocus={true}
-                                    className='ap-textarea w-full resize-none p-2 text-[1.5rem]'
+                                    className='ap-textarea w-full resize-none bg-transparent p-2 text-[1.5rem]'
+                                    disabled={noteMutation.isLoading}
                                     placeholder='What&apos;s new?'
-                                    rows={1}
-                                >
-                                </textarea>
+                                    rows={3}
+                                    value={content}
+                                    onChange={handleChange}
+                                />
                             </FormPrimitive.Control>
                         </FormPrimitive.Field>
                     </div>
diff --git a/apps/admin-x-activitypub/src/hooks/useActivityPubQueries.ts b/apps/admin-x-activitypub/src/hooks/useActivityPubQueries.ts
index dc497f9289..317c24f94a 100644
--- a/apps/admin-x-activitypub/src/hooks/useActivityPubQueries.ts
+++ b/apps/admin-x-activitypub/src/hooks/useActivityPubQueries.ts
@@ -436,3 +436,43 @@ export function useThreadForUser(handle: string, id: string) {
 
     return {threadQuery, addToThread};
 }
+
+export function useNoteMutationForUser(handle: string) {
+    const queryClient = useQueryClient();
+
+    return useMutation({
+        async mutationFn({content}: {content: string}) {
+            const siteUrl = await getSiteUrl();
+            const api = createActivityPubAPI(handle, siteUrl);
+            return await api.note(content) as Activity;
+        },
+        onSuccess: (activity: Activity) => {
+            queryClient.setQueryData([`outbox:${handle}`], (current?: Activity[]) => {
+                if (current === undefined) {
+                    return current;
+                }
+
+                return [activity, ...current];
+            });
+
+            queryClient.setQueriesData([`activities:${handle}`], (current?: {pages: {data: Activity[]}[]}) => {
+                if (current === undefined) {
+                    return current;
+                }
+
+                return {
+                    ...current,
+                    pages: current.pages.map((page: {data: Activity[]}, index: number) => {
+                        if (index === 0) {
+                            return {
+                                ...page,
+                                data: [activity, ...page.data]
+                            };
+                        }
+                        return page;
+                    })
+                };
+            });
+        }
+    });
+}