diff --git a/lib/pact_broker/pacts/repository.rb b/lib/pact_broker/pacts/repository.rb
index ba867cee4..71ef54fb8 100644
--- a/lib/pact_broker/pacts/repository.rb
+++ b/lib/pact_broker/pacts/repository.rb
@@ -187,13 +187,20 @@ def find_all_revisions consumer_name, consumer_version, provider_name
           .order(:consumer_version_order, :revision_number).collect(&:to_domain_with_content)
       end
 
-      def find_previous_pact pact
-        LatestPactPublicationsByConsumerVersion
-          .eager(:tags)
-          .consumer(pact.consumer.name)
-          .provider(pact.provider.name)
-          .consumer_version_order_before(pact.consumer_version.order)
-          .latest.collect(&:to_domain_with_content)[0]
+      def find_previous_pact pact, tag = nil
+        query = LatestPactPublicationsByConsumerVersion
+            .eager(:tags)
+            .consumer(pact.consumer.name)
+            .provider(pact.provider.name)
+
+        if tag == :untagged
+          query = query.untagged
+        elsif tag
+          query = query.tag(tag)
+        end
+
+        query.consumer_version_order_before(pact.consumer_version.order)
+            .latest.collect(&:to_domain_with_content)[0]
       end
 
       def find_next_pact pact
diff --git a/lib/pact_broker/pacts/service.rb b/lib/pact_broker/pacts/service.rb
index d70336152..bfceb7581 100644
--- a/lib/pact_broker/pacts/service.rb
+++ b/lib/pact_broker/pacts/service.rb
@@ -104,8 +104,8 @@ def find_distinct_pacts_between consumer, options
 
       # TODO also take into account overridden revisions
       def pact_is_new_or_pact_has_changed_since_previous_version? pact
-        previous_pact = pact_repository.find_previous_pact pact
-        previous_pact.nil? || pact.json_content != previous_pact.json_content
+        previous_pacts = find_previous_pacts pact
+        previous_pacts.any? { |previous_pact| previous_pact.nil? || pact.json_content != previous_pact.json_content}
       end
 
       private
@@ -140,6 +140,14 @@ def trigger_webhooks pact
           logger.debug "Pact has not changed since previous version, not triggering webhooks"
         end
       end
+
+      def find_previous_pacts pact
+        if pact.consumer_version_tag_names.any?
+          pact.consumer_version_tag_names.map { |tag| pact_repository.find_previous_pact(pact, tag) }
+        else
+          [pact_repository.find_previous_pact(pact, :untagged)]
+        end
+      end
     end
   end
 end
diff --git a/spec/lib/pact_broker/pacts/repository_spec.rb b/spec/lib/pact_broker/pacts/repository_spec.rb
index 0f418a23d..0aa783363 100644
--- a/spec/lib/pact_broker/pacts/repository_spec.rb
+++ b/spec/lib/pact_broker/pacts/repository_spec.rb
@@ -513,27 +513,74 @@ module Pacts
             .create_consumer("Consumer")
             .create_consumer_version("1.2.2")
             .create_provider("Provider")
+            .create_consumer_version_tag("a_tag")
+            .create_pact
+            .create_consumer_version("1.2.3")
             .create_pact
             .create_consumer_version("1.2.4")
+            .create_consumer_version_tag("another_tag")
             .create_pact
-            .create_consumer_version("1.2.6")
+            .create_consumer_version("1.2.5")
+            .create_consumer_version_tag("a_tag")
+            .create_pact
+            .create_consumer_version("1.2.7")
+            .create_consumer_version_tag("another_tag")
             .create_pact
             .create_provider("Another Provider")
-            .create_consumer_version("1.2.5")
+            .create_consumer_version("1.2.6")
+            .create_consumer_version_tag("a_tag")
             .create_pact
         end
 
-        let(:pact) { Repository.new.find_latest_pact "Consumer", "Provider"  }
+        context "regardless of tag" do
+          context "when a previous version with a pact exists" do
 
-        subject  { Repository.new.find_previous_pact pact }
+            let(:pact) { Repository.new.find_latest_pact "Consumer", "Provider", "another_tag" }
 
-        it "finds the previous pact" do
-          expect(subject.consumer_version_number).to eq "1.2.4"
-          expect(subject.consumer_version.number).to eq "1.2.4"
+            subject  { Repository.new.find_previous_pact pact }
+
+            it "finds the previous pact" do
+              expect(subject.consumer_version_number).to eq "1.2.5"
+            end
+
+            it "sets the json_content" do
+              expect(subject.json_content).to_not be nil
+            end
+          end
         end
 
-        it "sets the json_content" do
-          expect(subject.json_content).to_not be nil
+        context "by tag" do
+          context "when a previous version with a pact with a specific tag exists" do
+
+            let(:pact) { Repository.new.find_latest_pact "Consumer", "Provider", "a_tag"  }
+
+            subject  { Repository.new.find_previous_pact pact, "a_tag" }
+
+            it "finds the previous pact" do
+              expect(subject.consumer_version_number).to eq "1.2.2"
+            end
+
+            it "sets the json_content" do
+              expect(subject.json_content).to_not be nil
+            end
+          end
+        end
+
+        context "that is untagged" do
+          context "when a previous version with a an untagged pact exists" do
+
+            let(:pact) { Repository.new.find_latest_pact "Consumer", "Provider"  }
+
+            subject  { Repository.new.find_previous_pact pact, :untagged }
+
+            it "finds the previous pact" do
+              expect(subject.consumer_version_number).to eq "1.2.3"
+            end
+
+            it "sets the json_content" do
+              expect(subject.json_content).to_not be nil
+            end
+          end
         end
       end
 
diff --git a/spec/lib/pact_broker/pacts/service_spec.rb b/spec/lib/pact_broker/pacts/service_spec.rb
index 5bbf915ad..8319692cf 100644
--- a/spec/lib/pact_broker/pacts/service_spec.rb
+++ b/spec/lib/pact_broker/pacts/service_spec.rb
@@ -34,35 +34,83 @@ module Pacts
         let(:json_content) { { 'some' => 'json'}.to_json }
         let(:pact) { instance_double(PactBroker::Domain::Pact, json_content: json_content)}
 
-        before do
-          allow_any_instance_of(Pacts::Repository).to receive(:find_previous_pact).and_return(previous_pact)
-        end
-
         subject { Service.pact_is_new_or_pact_has_changed_since_previous_version? pact }
 
-        context "when a previous pact is found" do
-          let(:previous_pact) { instance_double(PactBroker::Domain::Pact, json_content: previous_json_content)}
-          let(:previous_json_content) { {'some' => 'json'}.to_json }
+        context "when consumer version is untagged" do
+          before do
+            allow(pact).to receive(:consumer_version_tag_names).and_return([]);
+            allow_any_instance_of(Pacts::Repository).to receive(:find_previous_pact).with(pact, :untagged).and_return(previous_pact)
+          end
+
+          context "when a previous pact is found" do
+            let(:previous_pact) { instance_double(PactBroker::Domain::Pact, json_content: previous_json_content)}
+            let(:previous_json_content) { {'some' => 'json'}.to_json }
 
-          context "when the json_content is the same" do
-            it "returns false" do
-              expect(subject).to be_falsey
+            context "when the json_content is the same" do
+              it "returns false" do
+                expect(subject).to be_falsey
+              end
+            end
+
+            context "when the json_content is not the same" do
+              let(:previous_json_content) { {'some-other' => 'json'}.to_json }
+              it "returns truthy" do
+                expect(subject).to be_truthy
+              end
             end
           end
 
-          context "when the json_content is not the same" do
-            let(:previous_json_content) { {'some-other' => 'json'}.to_json }
-            it "returns truthy" do
+          context "when a previous pact is not found" do
+            let(:previous_pact) { nil }
+
+            it "returns true" do
               expect(subject).to be_truthy
             end
           end
         end
 
-        context "when a previous pact is not found" do
-          let(:previous_pact) { nil }
+        context "when consumer version has two tags" do
+          before do
+            allow(pact).to receive(:consumer_version_tag_names).and_return(['tag_1', 'tag_2']);
+            allow_any_instance_of(Pacts::Repository).to receive(:find_previous_pact).with(pact, 'tag_1').and_return(previous_pact_tag_1)
+            allow_any_instance_of(Pacts::Repository).to receive(:find_previous_pact).with(pact, 'tag_2').and_return(previous_pact_tag_2)
+          end
+
+          context "when a previous pact is found for both tags" do
+            let(:previous_pact_tag_1) { instance_double(PactBroker::Domain::Pact, json_content: previous_json_content_tag_1)}
+            let(:previous_json_content_tag_1) { {'some' => 'json'}.to_json }
+
+            let(:previous_pact_tag_2) { instance_double(PactBroker::Domain::Pact, json_content: previous_json_content_tag_2)}
+            let(:previous_json_content_tag_2) { {'some' => 'json'}.to_json }
 
-          it "returns true" do
-            expect(subject).to be_truthy
+            context "when the json_content of both previous pacts and new pact is the same" do
+              it "returns false" do
+                expect(subject).to be_falsey
+              end
+            end
+
+            context "when the json_content of first previous pact is not the same" do
+              let(:previous_json_content_tag_1) { {'some-other' => 'json'}.to_json }
+              it "returns truthy" do
+                expect(subject).to be_truthy
+              end
+            end
+
+            context "when the json_content of second previous pact not the same" do
+              let(:previous_json_content_tag_2) { {'some-other' => 'json'}.to_json }
+              it "returns truthy" do
+                expect(subject).to be_truthy
+              end
+            end
+          end
+
+          context "when no previous pacts are found" do
+            let(:previous_pact_tag_1) { nil }
+            let(:previous_pact_tag_2) { nil }
+
+            it "returns true" do
+              expect(subject).to be_truthy
+            end
           end
         end
       end