diff --git a/app/models/loan.rb b/app/models/loan.rb
index 980c19885..4b6b88cca 100644
--- a/app/models/loan.rb
+++ b/app/models/loan.rb
@@ -5,6 +5,9 @@ class Loan < ApplicationRecord
     "mortgage" => { short: "Mortgage", long: "Mortgage" },
     "student" => { short: "Student Loan", long: "Student Loan" },
     "auto" => { short: "Auto Loan", long: "Auto Loan" },
+    "home_equity" => { short: "Home Equity", long: "Home Equity Loan" },
+    "line_of_credit" => { short: "Line of Credit", long: "Line of Credit" },
+    "business" => { short: "Business Loan", long: "Business Loan" },
     "other" => { short: "Other Loan", long: "Other Loan" }
   }.freeze
 
diff --git a/test/models/plaid_account/type_mappable_test.rb b/test/models/plaid_account/type_mappable_test.rb
index b3bc67083..ffc530bc2 100644
--- a/test/models/plaid_account/type_mappable_test.rb
+++ b/test/models/plaid_account/type_mappable_test.rb
@@ -32,4 +32,18 @@ class PlaidAccount::TypeMappableTest < ActiveSupport::TestCase
     assert_equal "other", @mock_processor.map_subtype("depository", nil)
     assert_equal "other", @mock_processor.map_subtype("depository", "unknown")
   end
+
+  test "every mapped subtype is a valid subtype of its accountable" do
+    PlaidAccount::TypeMappable::TYPE_MAPPING.each do |plaid_type, config|
+      accountable_class = config[:accountable]
+      next unless accountable_class.const_defined?(:SUBTYPES)
+
+      config[:subtype_mapping].each do |plaid_subtype, subtype|
+        assert_includes accountable_class::SUBTYPES.keys, subtype,
+          "TYPE_MAPPING maps #{plaid_type}/#{plaid_subtype.inspect} to #{subtype.inspect}, " \
+          "which is not a valid #{accountable_class} subtype — syncing such an account fails " \
+          "with 'Validation failed: Accountable subtype is not included in the list'"
+      end
+    end
+  end
 end