diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6eebe5c85..f9303f011 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -16,6 +16,7 @@ All notable changes to this project will be documented in this file.
 
 ### Fixed
 
+- Fix duplicate reports being sent when reporting some remote posts ([ClearlyClaire](https://github.com/mastodon/mastodon/pull/27355))
 - Fix clicking on already-opened thread post scrolling to the top of the thread ([ClearlyClaire](https://github.com/mastodon/mastodon/pull/27331), [ClearlyClaire](https://github.com/mastodon/mastodon/pull/27338), [ClearlyClaire](https://github.com/mastodon/mastodon/pull/27350))
 - Fix some remote posts getting truncated ([ClearlyClaire](https://github.com/mastodon/mastodon/pull/27307))
 - Fix some cases of infinite scroll code trying to fetch inaccessible posts in a loop ([ClearlyClaire](https://github.com/mastodon/mastodon/pull/27286))
diff --git a/app/services/report_service.rb b/app/services/report_service.rb
index 22d788d54..b4015d1cb 100644
--- a/app/services/report_service.rb
+++ b/app/services/report_service.rb
@@ -57,7 +57,7 @@ class ReportService < BaseService
 
   def forward_to_replied_to!
     # Send report to servers to which the account was replying to, so they also have a chance to act
-    inbox_urls = Account.remote.where(domain: forward_to_domains).where(id: Status.where(id: reported_status_ids).where.not(in_reply_to_account_id: nil).select(:in_reply_to_account_id)).inboxes - [@target_account.inbox_url]
+    inbox_urls = Account.remote.where(domain: forward_to_domains).where(id: Status.where(id: reported_status_ids).where.not(in_reply_to_account_id: nil).select(:in_reply_to_account_id)).inboxes - [@target_account.inbox_url, @target_account.shared_inbox_url]
 
     inbox_urls.each do |inbox_url|
       ActivityPub::DeliveryWorker.perform_async(payload, some_local_account.id, inbox_url)
diff --git a/spec/services/report_service_spec.rb b/spec/services/report_service_spec.rb
index 616368bf4..d3bcd5d31 100644
--- a/spec/services/report_service_spec.rb
+++ b/spec/services/report_service_spec.rb
@@ -36,7 +36,7 @@ RSpec.describe ReportService, type: :service do
         expect(report.uri).to_not be_nil
       end
 
-      context 'when reporting a reply' do
+      context 'when reporting a reply on a different remote server' do
         let(:remote_thread_account) { Fabricate(:account, domain: 'foo.com', protocol: :activitypub, inbox_url: 'http://foo.com/inbox') }
         let(:reported_status) { Fabricate(:status, account: remote_account, thread: Fabricate(:status, account: remote_thread_account)) }
 
@@ -67,6 +67,25 @@ RSpec.describe ReportService, type: :service do
           end
         end
       end
+
+      context 'when reporting a reply on the same remote server as the person being replied-to' do
+        let(:remote_thread_account) { Fabricate(:account, domain: 'example.com', protocol: :activitypub, inbox_url: 'http://example.com/inbox') }
+        let(:reported_status) { Fabricate(:status, account: remote_account, thread: Fabricate(:status, account: remote_thread_account)) }
+
+        context 'when forward_to_domains includes both the replied-to domain and the origin domain' do
+          it 'sends ActivityPub payload only once' do
+            subject.call(source_account, remote_account, status_ids: [reported_status.id], forward: forward, forward_to_domains: [remote_account.domain])
+            expect(a_request(:post, 'http://example.com/inbox')).to have_been_made.once
+          end
+        end
+
+        context 'when forward_to_domains does not include the replied-to domain' do
+          it 'sends ActivityPub payload only once' do
+            subject.call(source_account, remote_account, status_ids: [reported_status.id], forward: forward)
+            expect(a_request(:post, 'http://example.com/inbox')).to have_been_made.once
+          end
+        end
+      end
     end
 
     context 'when forward is false' do