diff --git a/lib/arclight/traject/ead2_config.rb b/lib/arclight/traject/ead2_config.rb
index 8e6d66a2f..69491edd4 100644
--- a/lib/arclight/traject/ead2_config.rb
+++ b/lib/arclight/traject/ead2_config.rb
@@ -79,9 +79,10 @@
 
 to_field 'id' do |record, accumulator|
   id = record.at_xpath('/ead/eadheader/eadid')&.text
+  unitid = record.at_xpath('/ead/archdesc/did/unitid')&.text
   title = record.at_xpath('/ead/archdesc/did/unittitle')&.text
   repository = settings['repository']
-  accumulator << settings['id_normalizer'].constantize.new(id, title: title, repository: repository).to_s
+  accumulator << settings['id_normalizer'].constantize.new(id, unitid: unitid, title: title, repository: repository).to_s
 end
 
 to_field 'title_filing_ssi', extract_xpath('/ead/eadheader/filedesc/titlestmt/titleproper[@type="filing"]')
diff --git a/spec/lib/arclight/normalized_id_spec.rb b/spec/lib/arclight/normalized_id_spec.rb
index abcb99e3c..2527bbd8e 100644
--- a/spec/lib/arclight/normalized_id_spec.rb
+++ b/spec/lib/arclight/normalized_id_spec.rb
@@ -33,7 +33,9 @@
   end
 
   context 'when additional keyword arguments are supplied' do
-    subject(:normalized_id) { described_class.new('abc123.xml', title: 'a title', repository: 'repo').to_s }
+    subject(:normalized_id) do
+      described_class.new('abc123.xml', unitid: 'abc-123', title: 'a title', repository: 'repo').to_s
+    end
 
     it 'accepts the additional arguments without changing the output' do
       expect(normalized_id).to eq 'abc123-xml'