diff --git a/app/internal_packages/message-list/styles/message-list.less b/app/internal_packages/message-list/styles/message-list.less
index fb4e3fa51..7347e0b92 100644
--- a/app/internal_packages/message-list/styles/message-list.less
+++ b/app/internal_packages/message-list/styles/message-list.less
@@ -102,6 +102,12 @@ body.platform-win32 {
   }
 }
 
+.mode-splitVertical {
+  .message-nav-title {
+    display: none;
+  }
+}
+
 .hide-sidebar-button {
   font-size: @font-size-small;
   color: @text-color-subtle;
diff --git a/app/internal_packages/preferences/lib/main.tsx b/app/internal_packages/preferences/lib/main.tsx
index 100b26943..a1313685f 100644
--- a/app/internal_packages/preferences/lib/main.tsx
+++ b/app/internal_packages/preferences/lib/main.tsx
@@ -62,8 +62,9 @@ export function activate() {
     'Preferences',
     {},
     {
-      split: ['Preferences'],
       list: ['Preferences'],
+      split: ['Preferences'],
+      splitVertical: ['Preferences'],
     }
   );
 
diff --git a/app/internal_packages/preferences/lib/tabs/preferences-appearance.tsx b/app/internal_packages/preferences/lib/tabs/preferences-appearance.tsx
index 78e0522e2..18877f5a7 100644
--- a/app/internal_packages/preferences/lib/tabs/preferences-appearance.tsx
+++ b/app/internal_packages/preferences/lib/tabs/preferences-appearance.tsx
@@ -139,7 +139,7 @@ class AppearanceModeSwitch extends React.Component<
   };
 
   _renderModeOptions() {
-    return ['list', 'split'].map(mode => (
+    return ['list', 'split', 'splitVertical'].map(mode => (
       <AppearanceModeOption
         mode={mode}
         key={mode}
@@ -174,6 +174,7 @@ const AppearanceModeOption = function AppearanceModeOption(props) {
   const label = {
     list: localized('Single Panel'),
     split: localized('Two Panel'),
+    splitVertical: localized('Two Panel Vertical'),
   }[props.mode];
 
   return (
diff --git a/app/internal_packages/preferences/styles/preferences.less b/app/internal_packages/preferences/styles/preferences.less
index 3cb77d032..4241e5a83 100644
--- a/app/internal_packages/preferences/styles/preferences.less
+++ b/app/internal_packages/preferences/styles/preferences.less
@@ -136,7 +136,7 @@
   }
 
   .container-appearance {
-    width: 400px;
+    width: 600px;
     margin: 0 auto;
 
     input[type='radio'] {
@@ -156,7 +156,7 @@
     }
 
     .appearance-mode-switch {
-      max-width: 400px;
+      max-width: 600px;
       text-align: right;
 
       .appearance-mode {
diff --git a/app/internal_packages/thread-list/lib/main.ts b/app/internal_packages/thread-list/lib/main.ts
index 7bfae39b0..af6e6f843 100644
--- a/app/internal_packages/thread-list/lib/main.ts
+++ b/app/internal_packages/thread-list/lib/main.ts
@@ -2,6 +2,7 @@ import { ComponentRegistry, WorkspaceStore } from 'mailspring-exports';
 
 import ThreadList from './thread-list';
 import ThreadListToolbar from './thread-list-toolbar';
+import ThreadListVertical from './thread-list-vertical';
 import ThreadListEmptyFolderBar from './thread-list-empty-folder-bar';
 import MessageListToolbar from './message-list-toolbar';
 import SelectedItemsStack from './selected-items-stack';
@@ -17,6 +18,10 @@ export function activate() {
     location: WorkspaceStore.Location.ThreadList,
   });
 
+  ComponentRegistry.register(ThreadListVertical, {
+    location: WorkspaceStore.Location.ThreadListVertical,
+  });
+
   ComponentRegistry.register(SelectedItemsStack, {
     location: WorkspaceStore.Location.MessageList,
     modes: ['split'],
diff --git a/app/internal_packages/thread-list/lib/thread-list-vertical.tsx b/app/internal_packages/thread-list/lib/thread-list-vertical.tsx
new file mode 100644
index 000000000..5e0cdb4c4
--- /dev/null
+++ b/app/internal_packages/thread-list/lib/thread-list-vertical.tsx
@@ -0,0 +1,26 @@
+import React from 'react';
+import { InjectedComponentSet } from 'mailspring-component-kit';
+import { WorkspaceStore } from 'mailspring-exports';
+
+class ThreadListVertical extends React.Component<{}, { style: string; syncing: boolean }> {
+    static displayName = 'ThreadListVertical';
+
+    render() {
+
+        return (
+            <>
+                <div style={{ height: '50%', width: '100%', boxShadow: '0 0.5px 0 #dddddd' }}>
+                    <InjectedComponentSet
+                        matching={{ location: WorkspaceStore.Location.ThreadList }} />
+                </div>
+                <div style={{ height: '50%', width: '100%' }}>
+                    <InjectedComponentSet
+                        matching={{ location: WorkspaceStore.Location.MessageList }} />
+                </div>
+            </>
+        );
+    }
+
+}
+
+export default ThreadListVertical;
\ No newline at end of file
diff --git a/app/lang/de.json b/app/lang/de.json
index d859b24ed..c9b65b56a 100644
--- a/app/lang/de.json
+++ b/app/lang/de.json
@@ -504,6 +504,8 @@
   "Reading": "Lesen",
   "Reading Pane Off": "Lesefenster aus",
   "Reading Pane On": "Lesefenster ein",
+  "Horizontal Reading Pane": "Horizontales Lesefenster",
+  "Vertical Reading Pane": "Vertikales Lesefenster",
   "Rebuild": "Wiederherstellen",
   "Rebuild Cache...": "Cache neu erstellen...",
   "Recipient": "Empfänger:",
@@ -771,6 +773,7 @@
   "Twitter Handle": "Twitter Handle",
   "Twitter Profile Image": "Twitter Profilbild",
   "Two Panel": "Zwei Panel",
+  "Two Panel Vertical": "Zwei vertikale Panel",
   "Uhoh - that's a pro feature!": "Uhoh - das ist ein Pro-Feature!",
   "Unable to Add Account": "Account kann nicht hinzugefügt werden",
   "Unable to Start Local Server": "Der lokale Server konnte nicht gestartet werden",
diff --git a/app/menus/darwin.js b/app/menus/darwin.js
index 5d4af3e2b..e14a664c1 100644
--- a/app/menus/darwin.js
+++ b/app/menus/darwin.js
@@ -92,28 +92,42 @@ module.exports = {
         {
           label: localized('Reading Pane Off'),
           type: 'radio',
-          command: 'navigation:select-split-mode',
-          checked: true,
-          hideWhenDisabled: true,
-        },
-        {
-          label: localized('Reading Pane On'),
-          type: 'radio',
-          command: 'navigation:select-split-mode',
+          command: 'navigation:list-mode-off',
           checked: false,
           hideWhenDisabled: true,
         },
         {
           label: localized('Reading Pane Off'),
           type: 'radio',
-          command: 'navigation:select-list-mode',
+          command: 'navigation:list-mode-on',
+          checked: true,
+          hideWhenDisabled: true,
+        },
+        {
+          label: localized('Horizontal Reading Pane'),
+          type: 'radio',
+          command: 'navigation:split-mode-off',
           checked: false,
           hideWhenDisabled: true,
         },
         {
-          label: localized('Reading Pane On'),
+          label: localized('Horizontal Reading Pane'),
           type: 'radio',
-          command: 'navigation:select-list-mode',
+          command: 'navigation:split-mode-on',
+          checked: true,
+          hideWhenDisabled: true,
+        },
+        {
+          label: localized('Vertical Reading Pane'),
+          type: 'radio',
+          command: 'navigation:splitVertical-mode-off',
+          checked: false,
+          hideWhenDisabled: true,
+        },
+        {
+          label: localized('Vertical Reading Pane'),
+          type: 'radio',
+          command: 'navigation:splitVertical-mode-on',
           checked: true,
           hideWhenDisabled: true,
         },
diff --git a/app/menus/linux.js b/app/menus/linux.js
index c151b6f72..6354903c4 100644
--- a/app/menus/linux.js
+++ b/app/menus/linux.js
@@ -64,28 +64,42 @@ module.exports = {
         {
           label: localized('Reading Pane Off'),
           type: 'radio',
-          command: 'navigation:select-split-mode',
-          checked: true,
-          hideWhenDisabled: true,
-        },
-        {
-          label: localized('Reading Pane On'),
-          type: 'radio',
-          command: 'navigation:select-split-mode',
+          command: 'navigation:list-mode-off',
           checked: false,
           hideWhenDisabled: true,
         },
         {
           label: localized('Reading Pane Off'),
           type: 'radio',
-          command: 'navigation:select-list-mode',
+          command: 'navigation:list-mode-on',
+          checked: true,
+          hideWhenDisabled: true,
+        },
+        {
+          label: localized('Horizontal Reading Pane'),
+          type: 'radio',
+          command: 'navigation:split-mode-off',
           checked: false,
           hideWhenDisabled: true,
         },
         {
-          label: localized('Reading Pane On'),
+          label: localized('Horizontal Reading Pane'),
           type: 'radio',
-          command: 'navigation:select-list-mode',
+          command: 'navigation:split-mode-on',
+          checked: true,
+          hideWhenDisabled: true,
+        },
+        {
+          label: localized('Vertical Reading Pane'),
+          type: 'radio',
+          command: 'navigation:splitVertical-mode-off',
+          checked: false,
+          hideWhenDisabled: true,
+        },
+        {
+          label: localized('Vertical Reading Pane'),
+          type: 'radio',
+          command: 'navigation:splitVertical-mode-on',
           checked: true,
           hideWhenDisabled: true,
         },
diff --git a/app/menus/win32.js b/app/menus/win32.js
index ed547309d..82162af4b 100644
--- a/app/menus/win32.js
+++ b/app/menus/win32.js
@@ -39,28 +39,42 @@ module.exports = {
         {
           label: localized('Reading Pane Off'),
           type: 'radio',
-          command: 'navigation:select-split-mode',
-          checked: true,
-          hideWhenDisabled: true,
-        },
-        {
-          label: localized('Reading Pane On'),
-          type: 'radio',
-          command: 'navigation:select-split-mode',
+          command: 'navigation:list-mode-off',
           checked: false,
           hideWhenDisabled: true,
         },
         {
           label: localized('Reading Pane Off'),
           type: 'radio',
-          command: 'navigation:select-list-mode',
+          command: 'navigation:list-mode-on',
+          checked: true,
+          hideWhenDisabled: true,
+        },
+        {
+          label: localized('Horizontal Reading Pane'),
+          type: 'radio',
+          command: 'navigation:split-mode-off',
           checked: false,
           hideWhenDisabled: true,
         },
         {
-          label: localized('Reading Pane On'),
+          label: localized('Horizontal Reading Pane'),
           type: 'radio',
-          command: 'navigation:select-list-mode',
+          command: 'navigation:split-mode-on',
+          checked: true,
+          hideWhenDisabled: true,
+        },
+        {
+          label: localized('Vertical Reading Pane'),
+          type: 'radio',
+          command: 'navigation:splitVertical-mode-off',
+          checked: false,
+          hideWhenDisabled: true,
+        },
+        {
+          label: localized('Vertical Reading Pane'),
+          type: 'radio',
+          command: 'navigation:splitVertical-mode-on',
           checked: true,
           hideWhenDisabled: true,
         },
diff --git a/app/src/config-schema.ts b/app/src/config-schema.ts
index fc253cf1a..3dc50be5c 100644
--- a/app/src/config-schema.ts
+++ b/app/src/config-schema.ts
@@ -30,7 +30,7 @@ export default {
           mode: {
             type: 'string',
             default: 'list',
-            enum: ['split', 'list'],
+            enum: ['split', 'list', 'splitVertical'],
           },
           systemTray: {
             type: 'boolean',
diff --git a/app/src/flux/stores/workspace-store.ts b/app/src/flux/stores/workspace-store.ts
index 3fe0bda59..57abed19a 100644
--- a/app/src/flux/stores/workspace-store.ts
+++ b/app/src/flux/stores/workspace-store.ts
@@ -119,6 +119,7 @@ class WorkspaceStore extends MailspringStore {
         {
           list: ['RootSidebar', 'ThreadList'],
           split: ['RootSidebar', 'ThreadList', 'MessageList', 'MessageListSidebar'],
+          splitVertical: ['RootSidebar', 'ThreadListVertical', 'MessageListSidebar'],
         }
       );
       this.defineSheet('Thread', {}, { list: ['MessageList', 'MessageListSidebar'] });
@@ -195,6 +196,7 @@ class WorkspaceStore extends MailspringStore {
   };
 
   _onSelectLayoutMode = mode => {
+
     if (mode === this._preferredLayoutMode) {
       return;
     }
@@ -221,9 +223,9 @@ class WorkspaceStore extends MailspringStore {
         {
           'core:pop-sheet': () => this.popSheet(),
         },
-        this._preferredLayoutMode === 'list'
-          ? { 'navigation:select-split-mode': () => this._onSelectLayoutMode('split') }
-          : { 'navigation:select-list-mode': () => this._onSelectLayoutMode('list') }
+        this._preferredLayoutMode === 'list' ? { 'navigation:list-mode-on': () => this._onSelectLayoutMode('list') } : { 'navigation:list-mode-off': () => this._onSelectLayoutMode('list') },
+        this._preferredLayoutMode === 'split' ? { 'navigation:split-mode-on': () => this._onSelectLayoutMode('split') } : { 'navigation:split-mode-off': () => this._onSelectLayoutMode('split') },
+        this._preferredLayoutMode === 'splitVertical' ? { 'navigation:splitVertical-mode-on': () => this._onSelectLayoutMode('splitVertical') } : { 'navigation:splitVertical-mode-off': () => this._onSelectLayoutMode('splitVertical') },
       )
     );
   }
diff --git a/app/static/images/preferences/appearance/appearance-mode-splitVertical@2x.png b/app/static/images/preferences/appearance/appearance-mode-splitVertical@2x.png
new file mode 100644
index 000000000..c8c0bbe24
Binary files /dev/null and b/app/static/images/preferences/appearance/appearance-mode-splitVertical@2x.png differ