diff --git a/app/soapbox/actions/tags.ts b/app/soapbox/actions/tags.ts
new file mode 100644
index 000000000..2c394ba46
--- /dev/null
+++ b/app/soapbox/actions/tags.ts
@@ -0,0 +1,120 @@
+import api from '../api';
+
+import type { AxiosError } from 'axios';
+import type { AppDispatch, RootState } from 'soapbox/store';
+import type { APIEntity } from 'soapbox/types/entities';
+
+const HASHTAG_FETCH_REQUEST = 'HASHTAG_FETCH_REQUEST';
+const HASHTAG_FETCH_SUCCESS = 'HASHTAG_FETCH_SUCCESS';
+const HASHTAG_FETCH_FAIL    = 'HASHTAG_FETCH_FAIL';
+
+const HASHTAG_FOLLOW_REQUEST = 'HASHTAG_FOLLOW_REQUEST';
+const HASHTAG_FOLLOW_SUCCESS = 'HASHTAG_FOLLOW_SUCCESS';
+const HASHTAG_FOLLOW_FAIL    = 'HASHTAG_FOLLOW_FAIL';
+
+const HASHTAG_UNFOLLOW_REQUEST = 'HASHTAG_UNFOLLOW_REQUEST';
+const HASHTAG_UNFOLLOW_SUCCESS = 'HASHTAG_UNFOLLOW_SUCCESS';
+const HASHTAG_UNFOLLOW_FAIL    = 'HASHTAG_UNFOLLOW_FAIL';
+
+const fetchHashtag = (name: string) => (dispatch: AppDispatch, getState: () => RootState) => {
+  dispatch(fetchHashtagRequest());
+
+  api(getState).get(`/api/v1/tags/${name}`).then(({ data }) => {
+    dispatch(fetchHashtagSuccess(name, data));
+  }).catch(err => {
+    dispatch(fetchHashtagFail(err));
+  });
+};
+
+const fetchHashtagRequest = () => ({
+  type: HASHTAG_FETCH_REQUEST,
+});
+
+const fetchHashtagSuccess = (name: string, tag: APIEntity) => ({
+  type: HASHTAG_FETCH_SUCCESS,
+  name,
+  tag,
+});
+
+const fetchHashtagFail = (error: AxiosError) => ({
+  type: HASHTAG_FETCH_FAIL,
+  error,
+});
+
+const followHashtag = (name: string) => (dispatch: AppDispatch, getState: () => RootState) => {
+  dispatch(followHashtagRequest(name));
+
+  api(getState).post(`/api/v1/tags/${name}/follow`).then(({ data }) => {
+    dispatch(followHashtagSuccess(name, data));
+  }).catch(err => {
+    dispatch(followHashtagFail(name, err));
+  });
+};
+
+const followHashtagRequest = (name: string) => ({
+  type: HASHTAG_FOLLOW_REQUEST,
+  name,
+});
+
+const followHashtagSuccess = (name: string, tag: APIEntity) => ({
+  type: HASHTAG_FOLLOW_SUCCESS,
+  name,
+  tag,
+});
+
+const followHashtagFail = (name: string, error: AxiosError) => ({
+  type: HASHTAG_FOLLOW_FAIL,
+  name,
+  error,
+});
+
+const unfollowHashtag = (name: string) => (dispatch: AppDispatch, getState: () => RootState) => {
+  dispatch(unfollowHashtagRequest(name));
+
+  api(getState).post(`/api/v1/tags/${name}/unfollow`).then(({ data }) => {
+    dispatch(unfollowHashtagSuccess(name, data));
+  }).catch(err => {
+    dispatch(unfollowHashtagFail(name, err));
+  });
+};
+
+const unfollowHashtagRequest = (name: string) => ({
+  type: HASHTAG_UNFOLLOW_REQUEST,
+  name,
+});
+
+const unfollowHashtagSuccess = (name: string, tag: APIEntity) => ({
+  type: HASHTAG_UNFOLLOW_SUCCESS,
+  name,
+  tag,
+});
+
+const unfollowHashtagFail = (name: string, error: AxiosError) => ({
+  type: HASHTAG_UNFOLLOW_FAIL,
+  name,
+  error,
+});
+
+export {
+  HASHTAG_FETCH_REQUEST,
+  HASHTAG_FETCH_SUCCESS,
+  HASHTAG_FETCH_FAIL,
+  HASHTAG_FOLLOW_REQUEST,
+  HASHTAG_FOLLOW_SUCCESS,
+  HASHTAG_FOLLOW_FAIL,
+  HASHTAG_UNFOLLOW_REQUEST,
+  HASHTAG_UNFOLLOW_SUCCESS,
+  HASHTAG_UNFOLLOW_FAIL,
+  fetchHashtag,
+  fetchHashtagRequest,
+  fetchHashtagSuccess,
+  fetchHashtagFail,
+  followHashtag,
+  followHashtagRequest,
+  followHashtagSuccess,
+  followHashtagFail,
+  unfollowHashtag,
+  unfollowHashtagRequest,
+  unfollowHashtagSuccess,
+  unfollowHashtagFail,
+};
diff --git a/app/soapbox/components/ui/card/card.tsx b/app/soapbox/components/ui/card/card.tsx
index 6fc85a39a..2cc23b6b4 100644
--- a/app/soapbox/components/ui/card/card.tsx
+++ b/app/soapbox/components/ui/card/card.tsx
@@ -45,6 +45,12 @@ interface ICardHeader {
   backHref?: string,
   onBackClick?: (event: React.MouseEvent) => void
   className?: string
+  /** Callback when the card action is clicked. */
+  onActionClick?: () => void,
+  /** URL to the svg icon for the card action. */
+  actionIcon?: string,
+  /** Text for the action. */
+  actionTitle?: string,
   children?: React.ReactNode
 }
 
@@ -52,7 +58,7 @@ interface ICardHeader {
  * Card header container with back button.
  * Typically holds a CardTitle.
  */
-const CardHeader: React.FC<ICardHeader> = ({ className, children, backHref, onBackClick }): JSX.Element => {
+const CardHeader: React.FC<ICardHeader> = ({ className, children, backHref, onBackClick, onActionClick, actionIcon, actionTitle }): JSX.Element => {
   const intl = useIntl();
 
   const renderBackButton = () => {
@@ -64,7 +70,7 @@ const CardHeader: React.FC<ICardHeader> = ({ className, children, backHref, onBa
     const backAttributes = backHref ? { to: backHref } : { onClick: onBackClick };
 
     return (
-      <Comp {...backAttributes} className='text-gray-900 dark:text-gray-100 focus:ring-primary-500 focus:ring-2' aria-label={intl.formatMessage(messages.back)}>
+      <Comp {...backAttributes} className='p-0.5 -m-0.5 text-gray-900 dark:text-gray-100 focus:ring-primary-500 focus:ring-2 rounded-full' aria-label={intl.formatMessage(messages.back)}>
         <SvgIcon src={require('@tabler/icons/arrow-left.svg')} className='h-6 w-6 rtl:rotate-180' />
         <span className='sr-only' data-testid='back-button'>{intl.formatMessage(messages.back)}</span>
       </Comp>
@@ -76,6 +82,12 @@ const CardHeader: React.FC<ICardHeader> = ({ className, children, backHref, onBa
       {renderBackButton()}
 
       {children}
+
+      {onActionClick && actionIcon && (
+        <button className='p-0.5 -m-0.5 text-gray-900 dark:text-gray-100 focus:ring-primary-500 focus:ring-2 rounded-full' onClick={onActionClick} title={actionTitle}>
+          <SvgIcon src={actionIcon} className='h-6 w-6' />
+        </button>
+      )}
     </HStack>
   );
 };
@@ -86,7 +98,7 @@ interface ICardTitle {
 
 /** A card's title. */
 const CardTitle: React.FC<ICardTitle> = ({ title }): JSX.Element => (
-  <Text size='xl' weight='bold' tag='h1' data-testid='card-title' truncate>{title}</Text>
+  <Text className='grow' size='xl' weight='bold' tag='h1' data-testid='card-title' truncate>{title}</Text>
 );
 
 interface ICardBody {
diff --git a/app/soapbox/components/ui/column/column.tsx b/app/soapbox/components/ui/column/column.tsx
index 5ccf3ac42..7099b792d 100644
--- a/app/soapbox/components/ui/column/column.tsx
+++ b/app/soapbox/components/ui/column/column.tsx
@@ -7,10 +7,10 @@ import { useSoapboxConfig } from 'soapbox/hooks';
 
 import { Card, CardBody, CardHeader, CardTitle } from '../card/card';
 
-type IColumnHeader = Pick<IColumn, 'label' | 'backHref' |'className'>;
+type IColumnHeader = Pick<IColumn, 'label' | 'backHref' | 'className' | 'onActionClick' | 'actionIcon' | 'actionTitle'>;
 
 /** Contains the column title with optional back button. */
-const ColumnHeader: React.FC<IColumnHeader> = ({ label, backHref, className }) => {
+const ColumnHeader: React.FC<IColumnHeader> = ({ label, backHref, className, onActionClick, actionIcon, actionTitle }) => {
   const history = useHistory();
 
   const handleBackClick = () => {
@@ -27,7 +27,13 @@ const ColumnHeader: React.FC<IColumnHeader> = ({ label, backHref, className }) =
   };
 
   return (
-    <CardHeader className={className} onBackClick={handleBackClick}>
+    <CardHeader
+      className={className}
+      onBackClick={handleBackClick}
+      onActionClick={onActionClick}
+      actionIcon={actionIcon}
+      actionTitle={actionTitle}
+    >
       <CardTitle title={label} />
     </CardHeader>
   );
@@ -46,13 +52,19 @@ export interface IColumn {
   className?: string,
   /** Ref forwarded to column. */
   ref?: React.Ref<HTMLDivElement>
+  /** Callback when the column action is clicked. */
+  onActionClick?: () => void,
+  /** URL to the svg icon for the column action. */
+  actionIcon?: string,
+  /** Text for the action. */
+  actionTitle?: string,
   /** Children to display in the column. */
   children?: React.ReactNode
 }
 
 /** A backdrop for the main section of the UI. */
 const Column: React.FC<IColumn> = React.forwardRef((props, ref: React.ForwardedRef<HTMLDivElement>): JSX.Element => {
-  const { backHref, children, label, transparent = false, withHeader = true, className } = props;
+  const { backHref, children, label, transparent = false, withHeader = true, onActionClick, actionIcon, actionTitle, className } = props;
   const soapboxConfig = useSoapboxConfig();
 
   return (
@@ -75,6 +87,9 @@ const Column: React.FC<IColumn> = React.forwardRef((props, ref: React.ForwardedR
             label={label}
             backHref={backHref}
             className={classNames({ 'px-4 pt-4 sm:p-0': transparent })}
+            onActionClick={onActionClick}
+            actionIcon={actionIcon}
+            actionTitle={actionTitle}
           />
         )}
 
diff --git a/app/soapbox/features/hashtag-timeline/index.tsx b/app/soapbox/features/hashtag-timeline/index.tsx
index 133a96a5f..2587ff374 100644
--- a/app/soapbox/features/hashtag-timeline/index.tsx
+++ b/app/soapbox/features/hashtag-timeline/index.tsx
@@ -2,10 +2,11 @@ import React, { useEffect, useRef } from 'react';
 import { useIntl, defineMessages } from 'react-intl';
 
 import { connectHashtagStream } from 'soapbox/actions/streaming';
+import { fetchHashtag, followHashtag, unfollowHashtag } from 'soapbox/actions/tags';
 import { expandHashtagTimeline, clearTimeline } from 'soapbox/actions/timelines';
 import { Column } from 'soapbox/components/ui';
 import Timeline from 'soapbox/features/ui/components/timeline';
-import { useAppDispatch } from 'soapbox/hooks';
+import { useAppDispatch, useAppSelector, useFeatures } from 'soapbox/hooks';
 
 import type { Tag as TagEntity } from 'soapbox/types/entities';
 
@@ -18,6 +19,8 @@ const messages = defineMessages({
   any: { id: 'hashtag.column_header.tag_mode.any', defaultMessage: 'or {additional}' },
   all: { id: 'hashtag.column_header.tag_mode.all', defaultMessage: 'and {additional}' },
   none: { id: 'hashtag.column_header.tag_mode.none', defaultMessage: 'without {additional}' },
+  followHashtag: { id: 'hashtag.follow', defaultMessage: 'Follow hashtag' },
+  unfollowHashtag: { id: 'hashtag.unfollow', defaultMessage: 'Unfollow hashtag' },
   empty: { id: 'empty_column.hashtag', defaultMessage: 'There is nothing in this hashtag yet.' },
 });
 
@@ -32,9 +35,11 @@ export const HashtagTimeline: React.FC<IHashtagTimeline> = ({ params }) => {
   const intl = useIntl();
   const id = params?.id || '';
   const tags = params?.tags || { any: [], all: [], none: [] };
-
+  
+  const features = useFeatures();
   const dispatch = useAppDispatch();
   const disconnects = useRef<(() => void)[]>([]);
+  const tag = useAppSelector((state) => state.tags.get(id));
 
   // Mastodon supports displaying results from multiple hashtags.
   // https://github.com/mastodon/mastodon/issues/6359
@@ -88,9 +93,18 @@ export const HashtagTimeline: React.FC<IHashtagTimeline> = ({ params }) => {
     dispatch(expandHashtagTimeline(id, { maxId, tags }));
   };
 
+  const handleFollow = () => {
+    if (tag?.following) {
+      dispatch(unfollowHashtag(id));
+    } else {
+      dispatch(followHashtag(id));
+    }
+  };
+
   useEffect(() => {
     subscribe();
     dispatch(expandHashtagTimeline(id, { tags }));
+    dispatch(fetchHashtag(id));
 
     return () => {
       unsubscribe();
@@ -105,7 +119,13 @@ export const HashtagTimeline: React.FC<IHashtagTimeline> = ({ params }) => {
   }, [id]);
 
   return (
-    <Column label={title()} transparent>
+    <Column
+      label={title()}
+      transparent
+      onActionClick={features.followHashtags ? handleFollow : undefined}
+      actionIcon={tag?.following ? require('@tabler/icons/bell-ringing.svg') : require('@tabler/icons/bell.svg')}
+      actionTitle={intl.formatMessage(tag?.following ? messages.unfollowHashtag : messages.followHashtag)}
+    >
       <Timeline
         scrollKey='hashtag_timeline'
         timelineId={`hashtag:${id}`}
@@ -117,4 +137,4 @@ export const HashtagTimeline: React.FC<IHashtagTimeline> = ({ params }) => {
   );
 };
 
-export default HashtagTimeline;
\ No newline at end of file
+export default HashtagTimeline;
diff --git a/app/soapbox/normalizers/tag.ts b/app/soapbox/normalizers/tag.ts
index 6d0ebae14..fde58241f 100644
--- a/app/soapbox/normalizers/tag.ts
+++ b/app/soapbox/normalizers/tag.ts
@@ -19,6 +19,7 @@ export const TagRecord = ImmutableRecord({
   name: '',
   url: '',
   history: null as ImmutableList<History> | null,
+  following: false,
 });
 
 const normalizeHistoryList = (tag: ImmutableMap<string, any>) => {
diff --git a/app/soapbox/reducers/index.ts b/app/soapbox/reducers/index.ts
index 5b5cca999..1d1d71802 100644
--- a/app/soapbox/reducers/index.ts
+++ b/app/soapbox/reducers/index.ts
@@ -56,6 +56,7 @@ import status_hover_card from './status-hover-card';
 import status_lists from './status-lists';
 import statuses from './statuses';
 import suggestions from './suggestions';
+import tags from './tags';
 import timelines from './timelines';
 import trending_statuses from './trending-statuses';
 import trends from './trends';
@@ -120,6 +121,7 @@ const reducers = {
   announcements,
   compose_event,
   admin_user_index,
+  tags,
 };
 
 // Build a default state from all reducers: it has the key and `undefined`
diff --git a/app/soapbox/reducers/tags.ts b/app/soapbox/reducers/tags.ts
new file mode 100644
index 000000000..81488bb1e
--- /dev/null
+++ b/app/soapbox/reducers/tags.ts
@@ -0,0 +1,30 @@
+import { Map as ImmutableMap } from 'immutable';
+
+import {
+  HASHTAG_FETCH_SUCCESS,
+  HASHTAG_FOLLOW_REQUEST,
+  HASHTAG_FOLLOW_FAIL,
+  HASHTAG_UNFOLLOW_REQUEST,
+  HASHTAG_UNFOLLOW_FAIL,
+} from 'soapbox/actions/tags';
+import { normalizeTag } from 'soapbox/normalizers';
+
+import type { AnyAction } from 'redux';
+import type { Tag } from 'soapbox/types/entities';
+
+const initialState = ImmutableMap<string, Tag>();
+
+export default function tags(state = initialState, action: AnyAction) {
+  switch (action.type) {
+    case HASHTAG_FETCH_SUCCESS:
+      return state.set(action.name, normalizeTag(action.tag));
+    case HASHTAG_FOLLOW_REQUEST:
+    case HASHTAG_UNFOLLOW_FAIL:
+      return state.setIn([action.name, 'following'], true);
+    case HASHTAG_FOLLOW_FAIL:
+    case HASHTAG_UNFOLLOW_REQUEST:
+      return state.setIn([action.name, 'following'], false);
+    default:
+      return state;
+  }
+}
diff --git a/app/soapbox/utils/features.ts b/app/soapbox/utils/features.ts
index 39950a534..2f24c07f4 100644
--- a/app/soapbox/utils/features.ts
+++ b/app/soapbox/utils/features.ts
@@ -447,6 +447,13 @@ const getInstanceFeatures = (instance: Instance) => {
      */
     focalPoint: v.software === MASTODON && gte(v.compatVersion, '2.3.0'),
 
+    /**
+     * Ability to follow hashtags.
+     * @see POST /api/v1/tags/:name/follow
+     * @see POST /api/v1/tags/:name/unfollow
+     */
+    followHashtags: v.software === MASTODON && gte(v.compatVersion, '4.0.0'),
+
     /**
      * Ability to lock accounts and manually approve followers.
      * @see PATCH /api/v1/accounts/update_credentials