diff --git a/assets/runtime/config/gitlabhq/gitlab.yml b/assets/runtime/config/gitlabhq/gitlab.yml
index 2bc50aa2..0eb5c121 100644
--- a/assets/runtime/config/gitlabhq/gitlab.yml
+++ b/assets/runtime/config/gitlabhq/gitlab.yml
@@ -512,9 +512,9 @@ production: &base
         aws_secret_access_key: '{{AWS_BACKUP_SECRET_ACCESS_KEY}}'
       # The remote 'directory' to store your backups. For S3, this would be the bucket name.
       remote_directory: '{{AWS_BACKUP_BUCKET}}'
-    #   # Use multipart uploads when file size reaches 100MB, see
-    #   #  http://docs.aws.amazon.com/AmazonS3/latest/dev/uploadobjusingmpu.html
-    #   multipart_chunk_size: 104857600
+      # Use multipart uploads when file size reaches 100MB, see
+      #  http://docs.aws.amazon.com/AmazonS3/latest/dev/uploadobjusingmpu.html
+      multipart_chunk_size: {{AWS_BACKUP_MULTIPART_CHUNK_SIZE}}
     #   # Turns on AWS Server-Side Encryption with Amazon S3-Managed Keys for backups, this is optional
     #   # encryption: 'AES256'
       # Fog storage connection settings, see http://fog.io/storage/ .
diff --git a/assets/runtime/env-defaults b/assets/runtime/env-defaults
index a039b1b1..66a65bcf 100644
--- a/assets/runtime/env-defaults
+++ b/assets/runtime/env-defaults
@@ -157,7 +157,7 @@ AWS_BACKUP_PATH_STYLE=${AWS_BACKUP_PATH_STYLE:-false}
 AWS_BACKUP_ACCESS_KEY_ID=${AWS_BACKUP_ACCESS_KEY_ID}
 AWS_BACKUP_SECRET_ACCESS_KEY=${AWS_BACKUP_SECRET_ACCESS_KEY}
 AWS_BACKUP_BUCKET=${AWS_BACKUP_BUCKET}
-AWS_BACKUP_MULTIPART_CHUNK_SIZE=${AWS_BACKUP_MULTIPART_CHUNK_SIZE}
+AWS_BACKUP_MULTIPART_CHUNK_SIZE=${AWS_BACKUP_MULTIPART_CHUNK_SIZE:-104857600}
 
 ### GCS BACKUPS
 GCS_BACKUPS=${GCS_BACKUPS:-false}