diff --git a/lib/Segments/SegmentsRepository.php b/lib/Segments/SegmentsRepository.php
index 0dd6aa623e..f09a3dfa11 100644
--- a/lib/Segments/SegmentsRepository.php
+++ b/lib/Segments/SegmentsRepository.php
@@ -3,6 +3,7 @@
 namespace MailPoet\Segments;
 
 use DateTime;
+use MailPoet\ConflictException;
 use MailPoet\Doctrine\Repository;
 use MailPoet\Entities\DynamicSegmentFilterData;
 use MailPoet\Entities\DynamicSegmentFilterEntity;
@@ -94,6 +95,8 @@ class SegmentsRepository extends Repository {
 
   /**
    * @param DynamicSegmentFilterData[] $filtersData
+   * @throws ConflictException
+   * @throws NotFoundException
    */
   public function createOrUpdate(
     string $name,
@@ -110,6 +113,9 @@ class SegmentsRepository extends Repository {
       $segment->setName($name);
       $segment->setDescription($description);
     } else {
+      if (!$this->isNameUnique($name, $id)) {
+        throw new ConflictException("Could not create new segment with name [{$name}] because a segment with that name already exists.");
+      }
       $segment = new SegmentEntity($name, $type, $description);
       $this->persist($segment);
     }
diff --git a/tests/integration/Segments/SegmentsRepositoryTest.php b/tests/integration/Segments/SegmentsRepositoryTest.php
index a8647e52b1..73aad0f1d7 100644
--- a/tests/integration/Segments/SegmentsRepositoryTest.php
+++ b/tests/integration/Segments/SegmentsRepositoryTest.php
@@ -2,6 +2,7 @@
 
 namespace MailPoet\Segments;
 
+use MailPoet\ConflictException;
 use MailPoet\Entities\DynamicSegmentFilterData;
 use MailPoet\Entities\DynamicSegmentFilterEntity;
 use MailPoet\Entities\NewsletterEntity;
@@ -107,6 +108,14 @@ class SegmentsRepositoryTest extends \MailPoetTest {
     expect($count)->equals(2);
   }
 
+  public function testItChecksForDuplicateNameWhenCreatingNewSegment() {
+    $this->createDefaultSegment('Existing Segment');
+    $this->segmentsRepository->flush();
+    $this->expectException(ConflictException::class);
+    $this->expectExceptionMessage("Could not create new segment with name [Existing Segment] because a segment with that name already exists.");
+    $this->segmentsRepository->createOrUpdate('Existing Segment');
+  }
+
   private function createDefaultSegment(string $name): SegmentEntity {
     $segment = new SegmentEntity($name, SegmentEntity::TYPE_DEFAULT, 'description');
     $this->entityManager->persist($segment);