diff --git a/src/main/java/org/breedinginsight/brapi/v2/constants/BrAPIAdditionalInfoFields.java b/src/main/java/org/breedinginsight/brapi/v2/constants/BrAPIAdditionalInfoFields.java
index 611a5e5fb..d14663cd2 100644
--- a/src/main/java/org/breedinginsight/brapi/v2/constants/BrAPIAdditionalInfoFields.java
+++ b/src/main/java/org/breedinginsight/brapi/v2/constants/BrAPIAdditionalInfoFields.java
@@ -57,4 +57,5 @@ public final class BrAPIAdditionalInfoFields {
     public static final String OBS_UNIT_ID = "obsUnitID";
     public static final String GERMPLASM_NAME = "germplasmName";
     public static final String SUBMISSION_NAME = "submissionName";
+    public static final String EXP_UNIT_ID = "expUnitID";
 }
diff --git a/src/main/java/org/breedinginsight/brapi/v2/services/BrAPITrialService.java b/src/main/java/org/breedinginsight/brapi/v2/services/BrAPITrialService.java
index b11983b56..158ce952a 100644
--- a/src/main/java/org/breedinginsight/brapi/v2/services/BrAPITrialService.java
+++ b/src/main/java/org/breedinginsight/brapi/v2/services/BrAPITrialService.java
@@ -573,6 +573,8 @@ public BrAPIObservationUnit createSubObservationUnit(
         levelRelationships.add(expUnitLevel);
         position.setObservationLevelRelationships(levelRelationships);
 
+        observationUnit.putAdditionalInfoItem(BrAPIAdditionalInfoFields.EXP_UNIT_ID, expUnit.getObservationUnitName());
+
         // Set ObservationUnitPosition.
         observationUnit.setObservationUnitPosition(position);