diff --git a/app/constants/view.js b/app/constants/view.js
index f2e5c4a1f..d72516223 100644
--- a/app/constants/view.js
+++ b/app/constants/view.js
@@ -95,8 +95,16 @@ const ViewTypes = keyMirror({
     LANDSCAPE: null,
 });
 
+const RequiredServer = {
+    FULL_VERSION: 5.19,
+    MAJOR_VERSION: 5,
+    MIN_VERSION: 19,
+    PATCH_VERSION: 0,
+};
+
 export default {
     ...ViewTypes,
+    RequiredServer,
     POST_VISIBILITY_CHUNK_SIZE: 15,
     FEATURE_TOGGLE_PREFIX: 'feature_enabled_',
     EMBED_PREVIEW: 'embed_preview',
diff --git a/app/screens/channel/channel_base.js b/app/screens/channel/channel_base.js
index 600f547fa..19f68da4b 100644
--- a/app/screens/channel/channel_base.js
+++ b/app/screens/channel/channel_base.js
@@ -5,14 +5,16 @@ import React, {PureComponent} from 'react';
 import PropTypes from 'prop-types';
 import {intlShape} from 'react-intl';
 import {
+    Alert,
     Keyboard,
+    Linking,
     StyleSheet,
 } from 'react-native';
 import MaterialIcon from 'react-native-vector-icons/MaterialIcons';
 
 import {showModal, showModalOverCurrentContext} from '@actions/navigation';
 import LocalConfig from '@assets/config';
-import {NavigationTypes} from '@constants';
+import {NavigationTypes, ViewTypes} from '@constants';
 import EventEmitter from '@mm-redux/utils/event_emitter';
 import EphemeralStore from '@store/ephemeral_store';
 import {preventDoubleTap} from '@utils/tap';
@@ -37,6 +39,7 @@ export default class ChannelBase extends PureComponent {
         currentChannelId: PropTypes.string,
         currentTeamId: PropTypes.string,
         disableTermsModal: PropTypes.bool,
+        isSupportedServer: PropTypes.bool,
         teamName: PropTypes.string,
         theme: PropTypes.object.isRequired,
         showTermsOfService: PropTypes.bool,
@@ -67,31 +70,43 @@ export default class ChannelBase extends PureComponent {
     }
 
     componentDidMount() {
+        const {
+            actions,
+            currentChannelId,
+            currentTeamId,
+            disableTermsModal,
+            isSupportedServer,
+            showTermsOfService,
+            skipMetrics,
+        } = this.props;
         EventEmitter.on(NavigationTypes.BLUR_POST_DRAFT, this.blurPostDraft);
         EventEmitter.on('leave_team', this.handleLeaveTeam);
 
-        if (this.props.currentTeamId) {
-            this.loadChannels(this.props.currentTeamId);
+        if (currentTeamId) {
+            this.loadChannels(currentTeamId);
         } else {
-            this.props.actions.selectDefaultTeam();
+            actions.selectDefaultTeam();
         }
 
-        if (this.props.currentChannelId) {
-            PushNotifications.clearChannelNotifications(this.props.currentChannelId);
+        if (currentChannelId) {
+            PushNotifications.clearChannelNotifications(currentChannelId);
             requestAnimationFrame(() => {
-                this.props.actions.getChannelStats(this.props.currentChannelId);
+                actions.getChannelStats(currentChannelId);
             });
         }
 
-        if (tracker.initialLoad && !this.props.skipMetrics) {
-            this.props.actions.recordLoadTime('Start time', 'initialLoad');
+        if (tracker.initialLoad && !skipMetrics) {
+            actions.recordLoadTime('Start time', 'initialLoad');
         }
 
-        if (this.props.showTermsOfService && !this.props.disableTermsModal) {
+        if (showTermsOfService && !disableTermsModal) {
             this.showTermsOfServiceModal();
+        } else if (!isSupportedServer) {
+            // Only display the Alert if the TOS does not need to show first
+            this.showUnsupportedServer();
         }
 
-        if (!this.props.skipMetrics) {
+        if (!skipMetrics) {
             telemetry.end(['start:channel_screen']);
         }
     }
@@ -140,31 +155,6 @@ export default class ChannelBase extends PureComponent {
         }
     };
 
-    showTermsOfServiceModal = async () => {
-        const {intl} = this.context;
-        const {theme} = this.props;
-        const screen = 'TermsOfService';
-        const title = intl.formatMessage({id: 'mobile.tos_link', defaultMessage: 'Terms of Service'});
-        MaterialIcon.getImageSource('close', 20, theme.sidebarHeaderTextColor).then((closeButton) => {
-            const passProps = {closeButton};
-            const options = {
-                layout: {
-                    componentBackgroundColor: theme.centerChannelBg,
-                },
-                topBar: {
-                    visible: true,
-                    height: null,
-                    title: {
-                        color: theme.sidebarHeaderTextColor,
-                        text: title,
-                    },
-                },
-            };
-
-            showModalOverCurrentContext(screen, passProps, options);
-        });
-    };
-
     goToChannelInfo = preventDoubleTap(() => {
         const {intl} = this.context;
         const {theme} = this.props;
@@ -249,6 +239,62 @@ export default class ChannelBase extends PureComponent {
         return null;
     }
 
+    showTermsOfServiceModal = async () => {
+        const {intl} = this.context;
+        const {isSupportedServer, theme} = this.props;
+        const screen = 'TermsOfService';
+        const title = intl.formatMessage({id: 'mobile.tos_link', defaultMessage: 'Terms of Service'});
+        MaterialIcon.getImageSource('close', 20, theme.sidebarHeaderTextColor).then((closeButton) => {
+            const passProps = {
+                closeButton,
+                isSupportedServer,
+                showUnsupportedServer: this.showUnsupportedServer,
+            };
+            const options = {
+                layout: {
+                    componentBackgroundColor: theme.centerChannelBg,
+                },
+                topBar: {
+                    visible: true,
+                    height: null,
+                    title: {
+                        color: theme.sidebarHeaderTextColor,
+                        text: title,
+                    },
+                },
+            };
+
+            showModalOverCurrentContext(screen, passProps, options);
+        });
+    };
+
+    showUnsupportedServer = () => {
+        const {formatMessage} = this.context.intl;
+        const title = formatMessage({id: 'mobile.server_upgrade.title', defaultMessage: 'Server upgrade required'});
+        const message = formatMessage({
+            id: 'mobile.server_upgrade.alert_description',
+            defaultMessage: 'This server version is unsupported and users will be exposed to compatibility issues that cause crashes or severe bugs breaking core functionality of the app. Upgrading to server version {serverVersion} or later is required.',
+        }, {serverVersion: ViewTypes.RequiredServer.FULL_VERSION});
+        const cancel = {
+            text: formatMessage({id: 'mobile.server_upgrade.dismiss', defaultMessage: 'Dismiss'}),
+            style: 'default',
+        };
+        const learnMore = {
+            text: formatMessage({id: 'mobile.server_upgrade.learn_more', defaultMessage: 'Learn More'}),
+            style: 'cancel',
+            onPress: () => {
+                const url = 'https://mattermost.com/blog/support-for-esr-5-9-has-ended/';
+                if (Linking.canOpenURL(url)) {
+                    Linking.openURL(url);
+                }
+            },
+        };
+        const buttons = [cancel, learnMore];
+        const options = {cancelable: false};
+
+        Alert.alert(title, message, buttons, options);
+    };
+
     updateNativeScrollView = () => {
         if (this.keyboardTracker?.current) {
             this.keyboardTracker.current.resetScrollView(this.props.currentChannelId);
diff --git a/app/screens/channel/channel_base.test.js b/app/screens/channel/channel_base.test.js
index 975d56703..c2b22b943 100644
--- a/app/screens/channel/channel_base.test.js
+++ b/app/screens/channel/channel_base.test.js
@@ -62,6 +62,7 @@ describe('ChannelBase', () => {
 
         const wrapper = shallow(
             <ChannelBase {...baseProps}/>,
+            {context: {intl: {formatMessage: jest.fn()}}},
         );
 
         expect(mergeNavigationOptions.mock.calls).toEqual([]);
diff --git a/app/screens/channel/index.js b/app/screens/channel/index.js
index d276db377..27ba47077 100644
--- a/app/screens/channel/index.js
+++ b/app/screens/channel/index.js
@@ -7,20 +7,37 @@ import {connect} from 'react-redux';
 import {loadChannelsForTeam, selectInitialChannel} from '@actions/views/channel';
 import {recordLoadTime} from '@actions/views/root';
 import {selectDefaultTeam} from '@actions/views/select_team';
-import {getCurrentChannelId} from '@mm-redux/selectors/entities/channels';
-import {getCurrentTeam} from '@mm-redux/selectors/entities/teams';
-import {getTheme} from '@mm-redux/selectors/entities/preferences';
-import {shouldShowTermsOfService} from '@mm-redux/selectors/entities/users';
+import {ViewTypes} from '@constants';
 import {getChannelStats} from '@mm-redux/actions/channels';
+import {getCurrentChannelId} from '@mm-redux/selectors/entities/channels';
+import {getServerVersion} from '@mm-redux/selectors/entities/general';
+import {getTheme} from '@mm-redux/selectors/entities/preferences';
+import {getCurrentTeam} from '@mm-redux/selectors/entities/teams';
+import {getCurrentUserId, getCurrentUserRoles, shouldShowTermsOfService} from '@mm-redux/selectors/entities/users';
+import {isMinimumServerVersion} from '@mm-redux/utils/helpers';
+import {isSystemAdmin as checkIsSystemAdmin} from '@mm-redux/utils/user_utils';
 
 import Channel from './channel';
 
 function mapStateToProps(state) {
     const currentTeam = getCurrentTeam(state);
+    const roles = getCurrentUserId(state) ? getCurrentUserRoles(state) : '';
+    const isSystemAdmin = checkIsSystemAdmin(roles);
+    let isSupportedServer = true;
+
+    if (isSystemAdmin) {
+        isSupportedServer = isMinimumServerVersion(
+            getServerVersion(state),
+            ViewTypes.RequiredServer.MAJOR_VERSION,
+            ViewTypes.RequiredServer.MIN_VERSION,
+            ViewTypes.RequiredServer.PATCH_VERSION,
+        );
+    }
 
     return {
         currentTeamId: currentTeam?.id,
         currentChannelId: getCurrentChannelId(state),
+        isSupportedServer,
         teamName: currentTeam?.display_name,
         theme: getTheme(state),
         showTermsOfService: shouldShowTermsOfService(state),
diff --git a/app/screens/terms_of_service/terms_of_service.js b/app/screens/terms_of_service/terms_of_service.js
index 93217da06..541aa928c 100644
--- a/app/screens/terms_of_service/terms_of_service.js
+++ b/app/screens/terms_of_service/terms_of_service.js
@@ -30,6 +30,8 @@ export default class TermsOfService extends PureComponent {
         }).isRequired,
         componentId: PropTypes.string,
         closeButton: PropTypes.object,
+        isSupportedServer: PropTypes.bool,
+        showUnsupportedServer: PropTypes.func,
         siteName: PropTypes.string,
         theme: PropTypes.object,
     };
@@ -145,11 +147,18 @@ export default class TermsOfService extends PureComponent {
     };
 
     handleAcceptTerms = () => {
+        const onSuccess = () => {
+            const {isSupportedServer, showUnsupportedServer} = this.props;
+            dismissModal();
+
+            if (!isSupportedServer) {
+                showUnsupportedServer();
+            }
+        };
+
         this.registerUserAction(
             true,
-            () => {
-                dismissModal();
-            },
+            onSuccess,
             this.handleAcceptTerms,
         );
     };
@@ -189,7 +198,6 @@ export default class TermsOfService extends PureComponent {
         });
 
         const {data} = await actions.updateMyTermsOfServiceStatus(this.state.termsId, accepted);
-
         this.setState({
             loading: false,
         });
diff --git a/app/screens/terms_of_service/terms_of_service.test.js b/app/screens/terms_of_service/terms_of_service.test.js
index 4ce021837..4bb650ab0 100644
--- a/app/screens/terms_of_service/terms_of_service.test.js
+++ b/app/screens/terms_of_service/terms_of_service.test.js
@@ -7,6 +7,7 @@ import {shallow} from 'enzyme';
 import Preferences from '@mm-redux/constants/preferences';
 
 import * as NavigationActions from '@actions/navigation';
+import TestHelper from 'test/test_helper';
 
 import TermsOfService from './terms_of_service.js';
 
@@ -23,16 +24,18 @@ jest.mock('@utils/theme', () => {
 describe('TermsOfService', () => {
     const actions = {
         getTermsOfService: jest.fn(),
-        updateMyTermsOfServiceStatus: jest.fn(),
+        updateMyTermsOfServiceStatus: jest.fn().mockResolvedValue({data: true}),
         logout: jest.fn(),
     };
 
     const baseProps = {
         actions,
-        theme: Preferences.THEMES.default,
         closeButton: {},
-        siteName: 'Mattermost',
         componentId: 'component-id',
+        isSupportedServer: true,
+        siteName: 'Mattermost',
+        showUnsupportedServer: jest.fn(),
+        theme: Preferences.THEMES.default,
     };
 
     test('should match snapshot', () => {
@@ -130,4 +133,35 @@ describe('TermsOfService', () => {
         wrapper.instance().closeTermsAndLogout();
         expect(baseProps.actions.logout).toHaveBeenCalledTimes(1);
     });
+
+    test('should NOT call showUnsupportedServer on acceptTerms if server is supported', async () => {
+        const wrapper = shallow(
+            <TermsOfService
+                {...baseProps}
+            />,
+            {context: {intl: {formatMessage: jest.fn()}}},
+        );
+
+        wrapper.setState({loading: false, termsId: 1, termsText: 'Terms Text'});
+        wrapper.instance().handleAcceptTerms();
+        TestHelper.wait(100).then(() => {
+            expect(baseProps.showUnsupportedServer).not.toHaveBeenCalled();
+        });
+    });
+
+    test('should call showUnsupportedServer on acceptTerms if server not supported', async () => {
+        const wrapper = shallow(
+            <TermsOfService
+                {...baseProps}
+                isSupportedServer={false}
+            />,
+            {context: {intl: {formatMessage: jest.fn()}}},
+        );
+
+        wrapper.setState({loading: false, termsId: 1, termsText: 'Terms Text'});
+        wrapper.instance().handleAcceptTerms();
+        TestHelper.wait(100).then(() => {
+            expect(baseProps.showUnsupportedServer).toHaveBeenCalledTimes(1);
+        });
+    });
 });
diff --git a/assets/base/i18n/en.json b/assets/base/i18n/en.json
index f25743d4a..c910949a3 100644
--- a/assets/base/i18n/en.json
+++ b/assets/base/i18n/en.json
@@ -453,8 +453,11 @@
   "mobile.server_link.unreachable_team.error": "This link belongs to a deleted team or to a team to which you do not have access.",
   "mobile.server_ssl.error.text": "The certificate from {host} is not trusted.\n\nPlease contact your System Administrator to resolve the certificate issues and allow connections to this server.",
   "mobile.server_ssl.error.title": "Untrusted Certificate",
+  "mobile.server_upgrade.alert_description": "This server version is unsupported and users will be exposed to compatibility issues that cause crashes or severe bugs breaking core functionality of the app. Upgrading to server version {serverVersion} or later is required.",
   "mobile.server_upgrade.button": "OK",
   "mobile.server_upgrade.description": "\nA server upgrade is required to use the Mattermost app. Please ask your System Administrator for details.\n",
+  "mobile.server_upgrade.dismiss": "Dismiss",
+  "mobile.server_upgrade.learn_more": "Learn More",
   "mobile.server_upgrade.title": "Server upgrade required",
   "mobile.server_url.invalid_format": "URL must start with http:// or https://",
   "mobile.session_expired": "Session Expired: Please log in to continue receiving notifications. Sessions for {siteName} are configured to expire every {daysCount, number} {daysCount, plural, one {day} other {days}}.",