diff --git a/lib/Controller/PageController.php b/lib/Controller/PageController.php
index 241955ec04..f5e0e05708 100644
--- a/lib/Controller/PageController.php
+++ b/lib/Controller/PageController.php
@@ -237,6 +237,7 @@ public function index(): TemplateResponse {
 			'sort-favorites' => $this->preferences->getPreference($this->userId, 'sort-favorites', 'false'),
 			'index-context-chat' => $this->contextChatSettingsService->isIndexingEnabled($this->userId) ? 'true' : 'false',
 			'compact-mode' => $this->preferences->getPreference($this->userId, 'compact-mode', 'false'),
+			'auto-mark-as-read' => $this->preferences->getPreference($this->userId, 'auto-mark-as-read', 'true'),
 		]);
 		$this->initialStateService->provideInitialState(
 			'prefill_displayName',
diff --git a/src/components/AppSettingsMenu.vue b/src/components/AppSettingsMenu.vue
index 162fb86414..f88fdde858 100755
--- a/src/components/AppSettingsMenu.vue
+++ b/src/components/AppSettingsMenu.vue
@@ -113,6 +113,12 @@
 							:disabled="loadingPrioritySettings">
 							{{ prioritySettingsText }}
 						</NcFormBoxSwitch>
+
+						<NcFormBoxSwitch
+							v-model="autoMarkAsRead"
+							:disabled="loadingAutoMarkAsRead">
+							{{ t('mail', 'Automatically mark messages as read when opened') }}
+						</NcFormBoxSwitch>
 					</NcFormBox>
 
 					<NcRadioGroup :model-value="useBottomReplies" :label="t('mail', 'Reply position')" @update:modelValue="onToggleButtonReplies">
@@ -372,6 +378,7 @@ export default {
 			loadingAvatarSettings: false,
 			prioritySettingsText: t('mail', 'Search the body of messages in priority Inbox'),
 			loadingPrioritySettings: false,
+			loadingAutoMarkAsRead: false,
 
 			optOutSettingsText: t('mail', 'Activate'),
 			loadingOptOutSettings: false,
@@ -451,6 +458,16 @@ export default {
 			},
 		},
 
+		autoMarkAsRead: {
+			get() {
+				return this.mainStore.getPreference('auto-mark-as-read', 'true') === 'true'
+			},
+
+			set(value) {
+				this.onToggleAutoMarkAsRead(value)
+			},
+		},
+
 		useExternalAvatars: {
 			get() {
 				return this.mainStore.getPreference('external-avatars', 'true') === 'true'
@@ -652,6 +669,22 @@ export default {
 			}
 		},
 
+		async onToggleAutoMarkAsRead(enabled) {
+			this.loadingAutoMarkAsRead = true
+
+			try {
+				await this.mainStore.savePreference({
+					key: 'auto-mark-as-read',
+					value: enabled ? 'true' : 'false',
+				})
+			} catch (error) {
+				Logger.error('could not save preferences', { error })
+				showError(t('mail', 'Could not update preference'))
+			} finally {
+				this.loadingAutoMarkAsRead = false
+			}
+		},
+
 		async onToggleSortFavorites(enabled) {
 			this.loadingSortFavorites = true
 
diff --git a/src/components/ThreadEnvelope.vue b/src/components/ThreadEnvelope.vue
index 4f3602823e..da928a1eb8 100644
--- a/src/components/ThreadEnvelope.vue
+++ b/src/components/ThreadEnvelope.vue
@@ -845,7 +845,8 @@ export default {
 					clearTimeout(loadingTimeout)
 				}
 
-				if (!this.envelope.flags.seen && this.hasSeenAcl) {
+				const autoMarkAsRead = this.mainStore.getPreference('auto-mark-as-read', 'true') === 'true'
+				if (autoMarkAsRead && !this.envelope.flags.seen && this.hasSeenAcl) {
 					logger.info('Starting timer to mark message as seen/read')
 					this.seenTimer = setTimeout(() => {
 						this.mainStore.toggleEnvelopeSeen({ envelope: this.envelope })
diff --git a/src/init.js b/src/init.js
index d23a556aa5..8b11da9de1 100644
--- a/src/init.js
+++ b/src/init.js
@@ -98,6 +98,10 @@ export default function initAfterAppCreation() {
 		key: 'compact-mode',
 		value: preferences['compact-mode'],
 	})
+	mainStore.savePreferenceMutation({
+		key: 'auto-mark-as-read',
+		value: preferences['auto-mark-as-read'],
+	})
 
 	mainStore.setQuickActions(loadState('mail', 'quick-actions', []))
 
diff --git a/tests/Unit/Controller/PageControllerTest.php b/tests/Unit/Controller/PageControllerTest.php
index 9b84226810..37873b9025 100644
--- a/tests/Unit/Controller/PageControllerTest.php
+++ b/tests/Unit/Controller/PageControllerTest.php
@@ -180,7 +180,7 @@ public function testIndex(): void {
 		$account1 = $this->createMock(Account::class);
 		$account2 = $this->createMock(Account::class);
 		$mailbox = $this->createStub(Mailbox::class);
-		$this->preferences->expects($this->exactly(14))
+		$this->preferences->expects($this->exactly(15))
 			->method('getPreference')
 			->willReturnMap([
 				[$this->userId, 'account-settings', '[]', json_encode([])],
@@ -197,6 +197,7 @@ public function testIndex(): void {
 				[$this->userId, 'smime-sign-aliases', '[]', '[]'],
 				[$this->userId, 'sort-favorites', 'false', 'false'],
 				[$this->userId, 'compact-mode', 'false', 'false'],
+				[$this->userId, 'auto-mark-as-read', 'true', 'true'],
 			]);
 		$this->accountService->expects($this->once())
 			->method('findByUserId')