diff --git a/include/boost/url.hpp b/include/boost/url.hpp
index 8ad141ceb..19f32c6d7 100644
--- a/include/boost/url.hpp
+++ b/include/boost/url.hpp
@@ -14,7 +14,7 @@
 
 #include <boost/url/authority_view.hpp>
 #include <boost/url/error.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/host_type.hpp>
 #include <boost/url/ipv4_address.hpp>
 #include <boost/url/ipv6_address.hpp>
diff --git a/include/boost/url/error.hpp b/include/boost/url/error.hpp
index 7bbc5f09f..74db67603 100644
--- a/include/boost/url/error.hpp
+++ b/include/boost/url/error.hpp
@@ -11,7 +11,7 @@
 #define BOOST_URL_ERROR_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <stdexcept>
 
 namespace boost {
diff --git a/include/boost/url/error_type.hpp b/include/boost/url/error_types.hpp
similarity index 98%
rename from include/boost/url/error_type.hpp
rename to include/boost/url/error_types.hpp
index 6e55bb109..cb06209d0 100644
--- a/include/boost/url/error_type.hpp
+++ b/include/boost/url/error_types.hpp
@@ -7,8 +7,8 @@
 // Official repository: https://github.com/CPPAlliance/url
 //
 
-#ifndef BOOST_URL_ERROR_TYPE_HPP
-#define BOOST_URL_ERROR_TYPE_HPP
+#ifndef BOOST_URL_ERROR_TYPES_HPP
+#define BOOST_URL_ERROR_TYPES_HPP
 
 #include <boost/url/detail/config.hpp>
 #include <boost/system/error_code.hpp>
diff --git a/include/boost/url/grammar/dec_octet_rule.hpp b/include/boost/url/grammar/dec_octet_rule.hpp
index 733cfb902..bd072d7f9 100644
--- a/include/boost/url/grammar/dec_octet_rule.hpp
+++ b/include/boost/url/grammar/dec_octet_rule.hpp
@@ -11,7 +11,7 @@
 #define BOOST_URL_GRAMMAR_DEC_OCTET_RULE_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 
 namespace boost {
 namespace urls {
diff --git a/include/boost/url/grammar/detail/tuple.hpp b/include/boost/url/grammar/detail/tuple.hpp
index bdc049de2..bf1ee186a 100644
--- a/include/boost/url/grammar/detail/tuple.hpp
+++ b/include/boost/url/grammar/detail/tuple.hpp
@@ -12,7 +12,7 @@
 #define BOOST_URL_GRAMMAR_DETAIL_TUPLE_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/detail/empty_value.hpp>
 #include <boost/mp11/algorithm.hpp>
 #include <boost/mp11/function.hpp>
diff --git a/include/boost/url/grammar/error.hpp b/include/boost/url/grammar/error.hpp
index beb180cc5..8c9b0a70e 100644
--- a/include/boost/url/grammar/error.hpp
+++ b/include/boost/url/grammar/error.hpp
@@ -11,7 +11,7 @@
 #define BOOST_URL_GRAMMAR_ERROR_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 
 namespace boost {
 namespace urls {
diff --git a/include/boost/url/grammar/literal_rule.hpp b/include/boost/url/grammar/literal_rule.hpp
index 2cecbc95c..779c26a95 100644
--- a/include/boost/url/grammar/literal_rule.hpp
+++ b/include/boost/url/grammar/literal_rule.hpp
@@ -11,7 +11,7 @@
 #define BOOST_URL_GRAMMAR_LITERAL_RULE_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/string_view.hpp>
 #include <cstdlib>
 
diff --git a/include/boost/url/grammar/not_empty_rule.hpp b/include/boost/url/grammar/not_empty_rule.hpp
index 7380a96fb..c2ab575ef 100644
--- a/include/boost/url/grammar/not_empty_rule.hpp
+++ b/include/boost/url/grammar/not_empty_rule.hpp
@@ -11,7 +11,7 @@
 #define BOOST_URL_GRAMMAR_NOT_EMPTY_RULE_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/grammar/type_traits.hpp>
 
 namespace boost {
diff --git a/include/boost/url/grammar/optional_rule.hpp b/include/boost/url/grammar/optional_rule.hpp
index ddc9c53bf..24e327bc5 100644
--- a/include/boost/url/grammar/optional_rule.hpp
+++ b/include/boost/url/grammar/optional_rule.hpp
@@ -12,7 +12,7 @@
 
 #include <boost/url/detail/config.hpp>
 #include <boost/url/optional.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/assert.hpp>
 
 namespace boost {
diff --git a/include/boost/url/grammar/parse.hpp b/include/boost/url/grammar/parse.hpp
index e2a01d7db..339e29d31 100644
--- a/include/boost/url/grammar/parse.hpp
+++ b/include/boost/url/grammar/parse.hpp
@@ -11,7 +11,7 @@
 #define BOOST_URL_GRAMMAR_PARSE_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/string_view.hpp>
 #include <boost/url/grammar/type_traits.hpp>
 
diff --git a/include/boost/url/grammar/token_rule.hpp b/include/boost/url/grammar/token_rule.hpp
index 9effa89cc..b1b6d01e7 100644
--- a/include/boost/url/grammar/token_rule.hpp
+++ b/include/boost/url/grammar/token_rule.hpp
@@ -12,7 +12,7 @@
 
 #include <boost/url/detail/config.hpp>
 #include <boost/url/grammar/charset.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/string_view.hpp>
 
 namespace boost {
diff --git a/include/boost/url/grammar/tuple_rule.hpp b/include/boost/url/grammar/tuple_rule.hpp
index 5456765ce..c87a65c5a 100644
--- a/include/boost/url/grammar/tuple_rule.hpp
+++ b/include/boost/url/grammar/tuple_rule.hpp
@@ -11,7 +11,7 @@
 #define BOOST_URL_GRAMMAR_TUPLE_RULE_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/grammar/error.hpp>
 #include <boost/url/grammar/detail/tuple.hpp>
 #include <boost/mp11/algorithm.hpp>
diff --git a/include/boost/url/grammar/type_traits.hpp b/include/boost/url/grammar/type_traits.hpp
index 76b5ae8a8..a6c6712e5 100644
--- a/include/boost/url/grammar/type_traits.hpp
+++ b/include/boost/url/grammar/type_traits.hpp
@@ -11,7 +11,7 @@
 #define BOOST_URL_GRAMMAR_TYPE_TRAITS_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/grammar/detail/type_traits.hpp>
 #include <boost/type_traits/make_void.hpp>
 #include <type_traits>
diff --git a/include/boost/url/grammar/unsigned_rule.hpp b/include/boost/url/grammar/unsigned_rule.hpp
index 191271bc9..41caae2f1 100644
--- a/include/boost/url/grammar/unsigned_rule.hpp
+++ b/include/boost/url/grammar/unsigned_rule.hpp
@@ -12,7 +12,7 @@
 #define BOOST_URL_GRAMMAR_UNSIGNED_RULE_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/grammar/charset.hpp>
 #include <boost/url/string_view.hpp>
 #include <boost/static_assert.hpp>
diff --git a/include/boost/url/grammar/variant_rule.hpp b/include/boost/url/grammar/variant_rule.hpp
index 5b3307549..99fa457e1 100644
--- a/include/boost/url/grammar/variant_rule.hpp
+++ b/include/boost/url/grammar/variant_rule.hpp
@@ -11,7 +11,7 @@
 #define BOOST_URL_GRAMMAR_VARIANT_RULE_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/variant.hpp>
 #include <boost/url/grammar/detail/tuple.hpp>
 
diff --git a/include/boost/url/ipv4_address.hpp b/include/boost/url/ipv4_address.hpp
index 59cb5d50f..16d77e677 100644
--- a/include/boost/url/ipv4_address.hpp
+++ b/include/boost/url/ipv4_address.hpp
@@ -13,7 +13,7 @@
 
 #include <boost/url/detail/config.hpp>
 #include <boost/url/error.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/string_view.hpp>
 #include <string>
 #include <array>
diff --git a/include/boost/url/ipv6_address.hpp b/include/boost/url/ipv6_address.hpp
index 9fa28ebf4..6390e928d 100644
--- a/include/boost/url/ipv6_address.hpp
+++ b/include/boost/url/ipv6_address.hpp
@@ -13,7 +13,7 @@
 
 #include <boost/url/detail/config.hpp>
 #include <boost/url/error.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/string_view.hpp>
 #include <array>
 #include <cstdint>
diff --git a/include/boost/url/rfc/absolute_uri_rule.hpp b/include/boost/url/rfc/absolute_uri_rule.hpp
index 1085107b9..58bcaffa3 100644
--- a/include/boost/url/rfc/absolute_uri_rule.hpp
+++ b/include/boost/url/rfc/absolute_uri_rule.hpp
@@ -11,7 +11,7 @@
 #define BOOST_URL_RFC_ABSOLUTE_URI_RULE_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/url_view.hpp>
 
 namespace boost {
diff --git a/include/boost/url/rfc/authority_rule.hpp b/include/boost/url/rfc/authority_rule.hpp
index c7aa537ce..05f0d4e28 100644
--- a/include/boost/url/rfc/authority_rule.hpp
+++ b/include/boost/url/rfc/authority_rule.hpp
@@ -12,7 +12,7 @@
 
 #include <boost/url/detail/config.hpp>
 #include <boost/url/authority_view.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 
 namespace boost {
 namespace urls {
diff --git a/include/boost/url/rfc/detail/h16_rule.hpp b/include/boost/url/rfc/detail/h16_rule.hpp
index 8a6a96002..3825bae0b 100644
--- a/include/boost/url/rfc/detail/h16_rule.hpp
+++ b/include/boost/url/rfc/detail/h16_rule.hpp
@@ -11,7 +11,7 @@
 #define BOOST_URL_RFC_DETAIL_H16_RULE_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <cstdint>
 
 namespace boost {
diff --git a/include/boost/url/rfc/detail/host_rule.hpp b/include/boost/url/rfc/detail/host_rule.hpp
index bacc2de04..b29366d64 100644
--- a/include/boost/url/rfc/detail/host_rule.hpp
+++ b/include/boost/url/rfc/detail/host_rule.hpp
@@ -15,7 +15,7 @@
 #include <boost/url/string_view.hpp>
 #include <boost/url/ipv4_address.hpp>
 #include <boost/url/ipv6_address.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 
 namespace boost {
 namespace urls {
diff --git a/include/boost/url/rfc/detail/ip_literal_rule.hpp b/include/boost/url/rfc/detail/ip_literal_rule.hpp
index ab9da2ce9..9d06c2b02 100644
--- a/include/boost/url/rfc/detail/ip_literal_rule.hpp
+++ b/include/boost/url/rfc/detail/ip_literal_rule.hpp
@@ -12,7 +12,7 @@
 
 #include <boost/url/detail/config.hpp>
 #include <boost/url/ipv6_address.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/string_view.hpp>
 
 namespace boost {
diff --git a/include/boost/url/rfc/detail/ipvfuture_rule.hpp b/include/boost/url/rfc/detail/ipvfuture_rule.hpp
index be1251bb3..27eff2eb1 100644
--- a/include/boost/url/rfc/detail/ipvfuture_rule.hpp
+++ b/include/boost/url/rfc/detail/ipvfuture_rule.hpp
@@ -10,7 +10,7 @@
 #ifndef BOOST_URL_RFC_DETAIL_IPVFUTURE_RULE_HPP
 #define BOOST_URL_RFC_DETAIL_IPVFUTURE_RULE_HPP
 
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/string_view.hpp>
 
 namespace boost {
diff --git a/include/boost/url/rfc/detail/port_rule.hpp b/include/boost/url/rfc/detail/port_rule.hpp
index 4bf978b61..8fac7fe74 100644
--- a/include/boost/url/rfc/detail/port_rule.hpp
+++ b/include/boost/url/rfc/detail/port_rule.hpp
@@ -11,7 +11,7 @@
 #define BOOST_URL_RFC_DETAIL_PORT_RULE_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/string_view.hpp>
 #include <cstdint>
 
diff --git a/include/boost/url/rfc/detail/relative_part_rule.hpp b/include/boost/url/rfc/detail/relative_part_rule.hpp
index 0d1732d21..64b06c601 100644
--- a/include/boost/url/rfc/detail/relative_part_rule.hpp
+++ b/include/boost/url/rfc/detail/relative_part_rule.hpp
@@ -11,7 +11,7 @@
 #define BOOST_URL_RFC_DETAIL_RELATIVE_PART_RULE_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/pct_encoded_view.hpp>
 #include <boost/url/rfc/authority_rule.hpp>
 #include <boost/url/grammar/range_rule.hpp>
diff --git a/include/boost/url/rfc/detail/scheme_rule.hpp b/include/boost/url/rfc/detail/scheme_rule.hpp
index 7c624fb95..0d51fd1ba 100644
--- a/include/boost/url/rfc/detail/scheme_rule.hpp
+++ b/include/boost/url/rfc/detail/scheme_rule.hpp
@@ -11,7 +11,7 @@
 #define BOOST_URL_RFC_DETAIL_SCHEME_RULE_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/scheme.hpp>
 #include <boost/url/string_view.hpp>
 
diff --git a/include/boost/url/rfc/detail/userinfo_rule.hpp b/include/boost/url/rfc/detail/userinfo_rule.hpp
index b233e140f..6e393bdf2 100644
--- a/include/boost/url/rfc/detail/userinfo_rule.hpp
+++ b/include/boost/url/rfc/detail/userinfo_rule.hpp
@@ -11,7 +11,7 @@
 #define BOOST_URL_RFC_DETAIL_USERINFO_RULE_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/pct_encoded_view.hpp>
 #include <boost/url/string_view.hpp>
 
diff --git a/include/boost/url/rfc/ipv4_address_rule.hpp b/include/boost/url/rfc/ipv4_address_rule.hpp
index 2dd822d20..c65536a99 100644
--- a/include/boost/url/rfc/ipv4_address_rule.hpp
+++ b/include/boost/url/rfc/ipv4_address_rule.hpp
@@ -12,7 +12,7 @@
 
 #include <boost/url/detail/config.hpp>
 #include <boost/url/ipv4_address.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 
 namespace boost {
 namespace urls {
diff --git a/include/boost/url/rfc/ipv6_address_rule.hpp b/include/boost/url/rfc/ipv6_address_rule.hpp
index f2ce2773a..a3f110e9c 100644
--- a/include/boost/url/rfc/ipv6_address_rule.hpp
+++ b/include/boost/url/rfc/ipv6_address_rule.hpp
@@ -12,7 +12,7 @@
 
 #include <boost/url/detail/config.hpp>
 #include <boost/url/ipv6_address.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 
 namespace boost {
 namespace urls {
diff --git a/include/boost/url/rfc/pct_encoded_rule.hpp b/include/boost/url/rfc/pct_encoded_rule.hpp
index 93606ea73..41923edbb 100644
--- a/include/boost/url/rfc/pct_encoded_rule.hpp
+++ b/include/boost/url/rfc/pct_encoded_rule.hpp
@@ -13,7 +13,7 @@
 #include <boost/url/detail/config.hpp>
 #include <boost/url/pct_encoded_view.hpp>
 #include <boost/url/pct_encoding.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/string_view.hpp>
 #include <boost/url/grammar/charset.hpp>
 #include <boost/url/grammar/error.hpp>
diff --git a/include/boost/url/rfc/query_rule.hpp b/include/boost/url/rfc/query_rule.hpp
index 08a5bd8df..a2efb0982 100644
--- a/include/boost/url/rfc/query_rule.hpp
+++ b/include/boost/url/rfc/query_rule.hpp
@@ -11,7 +11,7 @@
 #define BOOST_URL_RFC_QUERY_RULE_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/params_encoded_view.hpp>
 #include <boost/url/query_param.hpp>
 #include <cstddef>
diff --git a/include/boost/url/rfc/relative_ref_rule.hpp b/include/boost/url/rfc/relative_ref_rule.hpp
index 4709252fb..498deab11 100644
--- a/include/boost/url/rfc/relative_ref_rule.hpp
+++ b/include/boost/url/rfc/relative_ref_rule.hpp
@@ -11,7 +11,7 @@
 #define BOOST_URL_RFC_RELATIVE_REF_RULE_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/url_view.hpp>
 
 namespace boost {
diff --git a/include/boost/url/rfc/uri_reference_rule.hpp b/include/boost/url/rfc/uri_reference_rule.hpp
index 39ccb3ec8..6047bdfa4 100644
--- a/include/boost/url/rfc/uri_reference_rule.hpp
+++ b/include/boost/url/rfc/uri_reference_rule.hpp
@@ -11,7 +11,7 @@
 #define BOOST_URL_RFC_URI_REFERENCE_RULE_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/url_view.hpp>
 
 namespace boost {
diff --git a/include/boost/url/rfc/uri_rule.hpp b/include/boost/url/rfc/uri_rule.hpp
index c31a083ae..99c9dc333 100644
--- a/include/boost/url/rfc/uri_rule.hpp
+++ b/include/boost/url/rfc/uri_rule.hpp
@@ -11,7 +11,7 @@
 #define BOOST_URL_RFC_URI_RULE_HPP
 
 #include <boost/url/detail/config.hpp>
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>
 #include <boost/url/url_view.hpp>
 
 namespace boost {
diff --git a/test/unit/CMakeLists.txt b/test/unit/CMakeLists.txt
index 09e823ced..62853762e 100644
--- a/test/unit/CMakeLists.txt
+++ b/test/unit/CMakeLists.txt
@@ -21,7 +21,7 @@ set(BOOST_URL_TESTS_FILES
     doc_container.cpp
     doc_grammar.cpp
     error.cpp
-    error_type.cpp
+    error_types.cpp
     grammar.cpp
     host_type.cpp
     ipv4_address.cpp
diff --git a/test/unit/Jamfile b/test/unit/Jamfile
index 41a04d06c..8ba222319 100644
--- a/test/unit/Jamfile
+++ b/test/unit/Jamfile
@@ -24,7 +24,7 @@ local SOURCES =
     ../../extra/test_main.cpp
     authority_view.cpp
     error.cpp
-    error_type.cpp
+    error_types.cpp
     grammar.cpp
     host_type.cpp
     ipv4_address.cpp
diff --git a/test/unit/error_type.cpp b/test/unit/error_types.cpp
similarity index 89%
rename from test/unit/error_type.cpp
rename to test/unit/error_types.cpp
index db168f5e9..3ca95a65a 100644
--- a/test/unit/error_type.cpp
+++ b/test/unit/error_types.cpp
@@ -8,4 +8,4 @@
 //
 
 // Test that header file is self-contained.
-#include <boost/url/error_type.hpp>
+#include <boost/url/error_types.hpp>