diff --git lib/csv.rb lib/csv.rb
index 54b820d..2edaf5a 100644
--- lib/csv.rb
+++ lib/csv.rb
@@ -2188,7 +2188,7 @@ def convert_fields(fields, headers = false)
 
     fields.map.with_index do |field, index|
       converters.each do |converter|
-        break if field.nil?
+        break if headers && field.nil?
         field = if converter.arity == 1  # straight field converter
           converter[field]
         else                             # FieldInfo converter
diff --git test/csv/test_data_converters.rb test/csv/test_data_converters.rb
index 89b6dd1..3a6f46f 100755
--- test/csv/test_data_converters.rb
+++ test/csv/test_data_converters.rb
@@ -175,6 +175,15 @@ def test_convert_with_custom_code_using_field_info_header
                   @parser.shift.fields )
   end
 
+  def test_custom_converter_with_blank_field
+    converter = lambda { |field| field.nil? }
+    row = nil
+    assert_nothing_raised(Exception) do
+      row = CSV.parse_line('nil,', converters: converter)
+    end
+    assert_equal([false, true], row);
+  end
+
   def test_shortcut_interface
     assert_equal( ["Numbers", ":integer", 1, ":float", 3.015],
                   CSV.parse_line(@data, converters: :numeric) )