diff --git a/lib/imap/sync.rb b/lib/imap/sync.rb
index 207d65c9493..ecad53a0d50 100644
--- a/lib/imap/sync.rb
+++ b/lib/imap/sync.rb
@@ -264,6 +264,7 @@ module Imap
         to_sync.each do |incoming_email|
           Logger.log("[IMAP] (#{@group.name}) Updating email and incoming email ID = #{incoming_email.id}")
           update_email(incoming_email)
+          incoming_email.update(imap_sync: false)
         end
       end
     end
@@ -305,6 +306,8 @@ module Imap
 
       tags.subtract([nil, ''])
 
+      return if !tagging_enabled?
+
       # TODO: Optimize tagging.
       # `DiscourseTagging.tag_topic_by_names` does a lot of lookups in the
       # database and some of them could be cached in this context.
@@ -312,7 +315,6 @@ module Imap
     end
 
     def update_email(incoming_email)
-      return if !SiteSetting.tagging_enabled || !SiteSetting.allow_staff_to_tag_pms
       return if !incoming_email || !incoming_email.imap_sync
 
       post = incoming_email.post
@@ -334,10 +336,10 @@ module Imap
       email = @provider.emails(incoming_email.imap_uid, ['FLAGS', 'LABELS']).first
       return if !email.present?
 
-      incoming_email.update(imap_sync: false)
-
       labels = email['LABELS']
       flags = email['FLAGS']
+      new_labels = []
+      new_flags = []
 
       # Topic has been deleted if it is not present from the post, so we need
       # to trash the IMAP server email
@@ -347,11 +349,6 @@ module Imap
         return @provider.trash(incoming_email.imap_uid)
       end
 
-      # Sync topic status and labels with email flags and labels.
-      tags = topic.tags.pluck(:name)
-      new_flags = tags.map { |tag| @provider.tag_to_flag(tag) }.reject(&:blank?)
-      new_labels = tags.map { |tag| @provider.tag_to_label(tag) }.reject(&:blank?)
-
       # the topic is archived, and the archive should be reflected in the IMAP
       # server
       topic_archived = topic.group_archived_messages.any?
@@ -374,10 +371,21 @@ module Imap
         @provider.archive(incoming_email.imap_uid)
       end
 
+      # Sync topic status and labels with email flags and labels.
+      if tagging_enabled?
+        tags = topic.tags.pluck(:name)
+        new_flags = tags.map { |tag| @provider.tag_to_flag(tag) }.reject(&:blank?)
+        new_labels = new_labels.concat(tags.map { |tag| @provider.tag_to_label(tag) }.reject(&:blank?))
+      end
+
       # regardless of whether the topic needs to be archived we still update
       # the flags and the labels
       @provider.store(incoming_email.imap_uid, 'FLAGS', flags, new_flags)
       @provider.store(incoming_email.imap_uid, 'LABELS', labels, new_labels)
     end
+
+    def tagging_enabled?
+      SiteSetting.tagging_enabled && SiteSetting.allow_staff_to_tag_pms
+    end
   end
 end
diff --git a/spec/components/imap/sync_spec.rb b/spec/components/imap/sync_spec.rb
index f1388f41bf5..f78cbd2eacd 100644
--- a/spec/components/imap/sync_spec.rb
+++ b/spec/components/imap/sync_spec.rb
@@ -100,6 +100,28 @@ describe Imap::Sync do
       expect(incoming_email.imap_group_id).to eq(group.id)
     end
 
+    context "when tagging not enabled" do
+      before do
+        SiteSetting.tagging_enabled = false
+        SiteSetting.allow_staff_to_tag_pms = false
+      end
+
+      it "creates a topic from an incoming email but with no tags added" do
+        expect { sync_handler.process }
+          .to change { Topic.count }.by(1)
+          .and change { Post.where(post_type: Post.types[:regular]).count }.by(1)
+          .and change { IncomingEmail.count }.by(1)
+
+        expect(group.imap_uid_validity).to eq(1)
+        expect(group.imap_last_uid).to eq(100)
+
+        topic = Topic.last
+        expect(topic.title).to eq(subject)
+        expect(topic.user.email).to eq(from)
+        expect(topic.tags).to eq([])
+      end
+    end
+
     it 'does not duplicate topics' do
       expect { sync_handler.process }
         .to change { Topic.count }.by(1)
@@ -451,7 +473,7 @@ describe Imap::Sync do
       it "does not archive email if not archived in discourse, it unarchives it instead" do
         @incoming_email.update(imap_sync: true)
         provider.stubs(:store).with(100, 'FLAGS', anything, anything)
-        provider.stubs(:store).with(100, 'LABELS', ["\\Inbox"], ["seen", "\\Inbox"])
+        provider.stubs(:store).with(100, 'LABELS', ["\\Inbox"], ["\\Inbox", "seen"])
 
         provider.expects(:archive).with(100).never
         provider.expects(:unarchive).with(100)