diff --git a/changelog/fix_and_error_for_rails_expanded_date_range.md b/changelog/fix_and_error_for_rails_expanded_date_range.md
new file mode 100644
index 0000000000..173f2c7bc2
--- /dev/null
+++ b/changelog/fix_and_error_for_rails_expanded_date_range.md
@@ -0,0 +1 @@
+* [#1254](https://github.com/rubocop/rubocop-rails/pull/1254): Fix an error for `Rails/ExpandedDateRange` when passing an argument only to the first method call for weeks. ([@earlopain][])
diff --git a/lib/rubocop/cop/rails/expanded_date_range.rb b/lib/rubocop/cop/rails/expanded_date_range.rb
index 073d41abe9..1655583097 100644
--- a/lib/rubocop/cop/rails/expanded_date_range.rb
+++ b/lib/rubocop/cop/rails/expanded_date_range.rb
@@ -51,7 +51,7 @@ def on_irange(node)
           return if allow?(begin_node, end_node)
 
           preferred_method = preferred_method(begin_node)
-          if begin_node.method?(:beginning_of_week) && begin_node.arguments.one?
+          if begin_node.method?(:beginning_of_week) && begin_node.arguments.one? && end_node.arguments.one?
             return unless same_argument?(begin_node, end_node)
 
             preferred_method << "(#{begin_node.first_argument.source})"
diff --git a/spec/rubocop/cop/rails/expanded_date_range_spec.rb b/spec/rubocop/cop/rails/expanded_date_range_spec.rb
index 039a713c2c..db9896b160 100644
--- a/spec/rubocop/cop/rails/expanded_date_range_spec.rb
+++ b/spec/rubocop/cop/rails/expanded_date_range_spec.rb
@@ -57,6 +57,12 @@
       RUBY
     end
 
+    it 'does not register an offense when using `date.beginning_of_week(:sunday)..date.end_of_week`' do
+      expect_no_offenses(<<~RUBY)
+        date.beginning_of_week(:sunday)..date.end_of_week
+      RUBY
+    end
+
     it 'registers and corrects an offense when using `date.beginning_of_year..date.end_of_year`' do
       expect_offense(<<~RUBY)
         date.beginning_of_year..date.end_of_year