diff --git a/src/core/include/mp-units/ext/type_traits.h b/src/core/include/mp-units/ext/type_traits.h
index a31b7214..25b47e95 100644
--- a/src/core/include/mp-units/ext/type_traits.h
+++ b/src/core/include/mp-units/ext/type_traits.h
@@ -136,7 +136,7 @@ concept one_of = (false || ... || std::same_as<T, Ts>);
 template<typename T, auto... Vs>
 [[nodiscard]] consteval bool contains()
 {
-  return (false || ... || is_same_v<decltype(Vs), T>);
+  return (false || ... || is_same_v<MP_UNITS_REMOVE_CONST(decltype(Vs)), T>);
 }
 
 template<template<typename...> typename T, typename... Ts>
@@ -160,7 +160,7 @@ template<typename T, std::same_as<T> auto V>
 template<typename T, auto V1, auto V2, auto... Vs>
 [[nodiscard]] consteval auto get()
 {
-  if constexpr (is_same_v<T, decltype(V1)>)
+  if constexpr (is_same_v<T, MP_UNITS_REMOVE_CONST(decltype(V1))>)
     return V1;
   else
     return get<T, V2, Vs...>();
diff --git a/src/core/include/mp-units/framework/quantity_point.h b/src/core/include/mp-units/framework/quantity_point.h
index 818eea6c..24eb9957 100644
--- a/src/core/include/mp-units/framework/quantity_point.h
+++ b/src/core/include/mp-units/framework/quantity_point.h
@@ -386,7 +386,7 @@ explicit(
 
 template<auto R1, auto PO1, typename Rep1, auto R2, typename Rep2>
 // TODO simplify when gcc catches up
-  requires ReferenceOf<decltype(R2), PO1.quantity_spec>
+  requires ReferenceOf<MP_UNITS_REMOVE_CONST(decltype(R2)), PO1.quantity_spec>
 [[nodiscard]] constexpr QuantityPoint auto operator+(const quantity_point<R1, PO1, Rep1>& qp,
                                                      const quantity<R2, Rep2>& q)
   requires requires { qp.quantity_ref_from(PO1) + q; }
@@ -399,7 +399,7 @@ template<auto R1, auto PO1, typename Rep1, auto R2, typename Rep2>
 
 template<auto R1, typename Rep1, auto R2, auto PO2, typename Rep2>
 // TODO simplify when gcc catches up
-  requires ReferenceOf<decltype(R1), PO2.quantity_spec>
+  requires ReferenceOf<MP_UNITS_REMOVE_CONST(decltype(R1)), PO2.quantity_spec>
 [[nodiscard]] constexpr QuantityPoint auto operator+(const quantity<R1, Rep1>& q,
                                                      const quantity_point<R2, PO2, Rep2>& qp)
   requires requires { q + qp.quantity_ref_from(PO2); }
@@ -423,7 +423,7 @@ template<Quantity Q, PointOrigin PO>
 
 template<auto R1, auto PO1, typename Rep1, auto R2, typename Rep2>
 // TODO simplify when gcc catches up
-  requires ReferenceOf<decltype(R2), PO1.quantity_spec>
+  requires ReferenceOf<MP_UNITS_REMOVE_CONST(decltype(R2)), PO1.quantity_spec>
 [[nodiscard]] constexpr QuantityPoint auto operator-(const quantity_point<R1, PO1, Rep1>& qp,
                                                      const quantity<R2, Rep2>& q)
   requires requires { qp.quantity_ref_from(PO1) - q; }
diff --git a/src/core/include/mp-units/framework/quantity_spec.h b/src/core/include/mp-units/framework/quantity_spec.h
index 1d16b67e..80ae5d79 100644
--- a/src/core/include/mp-units/framework/quantity_spec.h
+++ b/src/core/include/mp-units/framework/quantity_spec.h
@@ -483,7 +483,7 @@ struct kind_of_<Q> : quantity_spec<kind_of_<Q>, Q{}> {
 
 MP_UNITS_EXPORT template<detail::QuantitySpecWithNoSpecifiers auto Q>
   requires(detail::get_kind_tree_root(Q) == Q)
-inline constexpr kind_of_<decltype(Q)> kind_of;
+inline constexpr kind_of_<MP_UNITS_REMOVE_CONST(decltype(Q))> kind_of;
 
 namespace detail {
 
@@ -493,7 +493,7 @@ struct is_dimensionless<struct dimensionless> : std::true_type {};
 template<QuantitySpec auto... From, QuantitySpec Q>
 [[nodiscard]] consteval QuantitySpec auto clone_kind_of(Q q)
 {
-  if constexpr ((... && QuantityKindSpec<decltype(From)>))
+  if constexpr ((... && QuantityKindSpec<MP_UNITS_REMOVE_CONST(decltype(From))>))
     return kind_of<Q{}>;
   else
     return q;
diff --git a/src/core/include/mp-units/framework/reference.h b/src/core/include/mp-units/framework/reference.h
index 6bd334e2..746abb44 100644
--- a/src/core/include/mp-units/framework/reference.h
+++ b/src/core/include/mp-units/framework/reference.h
@@ -38,7 +38,7 @@ namespace mp_units {
 namespace detail {
 
 template<QuantitySpec auto Q, Unit auto U>
-using reference_t = reference<decltype(Q), decltype(U)>;
+using reference_t = reference<MP_UNITS_REMOVE_CONST(decltype(Q)), MP_UNITS_REMOVE_CONST(decltype(U))>;
 
 }
 
@@ -258,13 +258,13 @@ MP_UNITS_EXPORT_END
 namespace detail {
 
 template<AssociatedUnit auto To, AssociatedUnit From>
-[[nodiscard]] consteval decltype(To) clone_reference_with(From)
+[[nodiscard]] consteval MP_UNITS_REMOVE_CONST(decltype(To)) clone_reference_with(From)
 {
   return {};
 }
 
 template<Unit auto To, QuantitySpec QS, Unit U>
-[[nodiscard]] consteval reference<QS, decltype(To)> clone_reference_with(reference<QS, U>)
+[[nodiscard]] consteval reference<QS, MP_UNITS_REMOVE_CONST(decltype(To))> clone_reference_with(reference<QS, U>)
 {
   return {};
 }
diff --git a/src/core/include/mp-units/framework/system_reference.h b/src/core/include/mp-units/framework/system_reference.h
index 0bfcabae..bfc4b81a 100644
--- a/src/core/include/mp-units/framework/system_reference.h
+++ b/src/core/include/mp-units/framework/system_reference.h
@@ -68,9 +68,9 @@ struct system_reference {
   template<Unit U>
     requires(convertible(coherent_unit, U{}))
 #if MP_UNITS_COMP_MSVC
-  [[nodiscard]] constexpr decltype(reference<decltype(Q), U>{}) operator[](U) const
+  [[nodiscard]] constexpr decltype(reference<MP_UNITS_REMOVE_CONST(decltype(quantity_spec)), U>{}) operator[](U) const
 #else
-  [[nodiscard]] constexpr reference<decltype(Q), U> operator[](U) const
+  [[nodiscard]] constexpr reference<MP_UNITS_REMOVE_CONST(decltype(quantity_spec)), U> operator[](U) const
 #endif
   {
     return {};
diff --git a/src/systems/include/mp-units/systems/iec80000/binary_prefixes.h b/src/systems/include/mp-units/systems/iec80000/binary_prefixes.h
index 921ab90b..1f2e9660 100644
--- a/src/systems/include/mp-units/systems/iec80000/binary_prefixes.h
+++ b/src/systems/include/mp-units/systems/iec80000/binary_prefixes.h
@@ -42,14 +42,14 @@ template<PrefixableUnit U> struct yobi_ : prefixed_unit<"Yi", mag_power<2, 80>,
 
 MP_UNITS_EXPORT_BEGIN
 
-template<PrefixableUnit auto U> inline constexpr kibi_<decltype(U)> kibi;
-template<PrefixableUnit auto U> inline constexpr mebi_<decltype(U)> mebi;
-template<PrefixableUnit auto U> inline constexpr gibi_<decltype(U)> gibi;
-template<PrefixableUnit auto U> inline constexpr tebi_<decltype(U)> tebi;
-template<PrefixableUnit auto U> inline constexpr pebi_<decltype(U)> pebi;
-template<PrefixableUnit auto U> inline constexpr exbi_<decltype(U)> exbi;
-template<PrefixableUnit auto U> inline constexpr zebi_<decltype(U)> zebi;
-template<PrefixableUnit auto U> inline constexpr yobi_<decltype(U)> yobi;
+template<PrefixableUnit auto U> inline constexpr kibi_<MP_UNITS_REMOVE_CONST(decltype(U))> kibi;
+template<PrefixableUnit auto U> inline constexpr mebi_<MP_UNITS_REMOVE_CONST(decltype(U))> mebi;
+template<PrefixableUnit auto U> inline constexpr gibi_<MP_UNITS_REMOVE_CONST(decltype(U))> gibi;
+template<PrefixableUnit auto U> inline constexpr tebi_<MP_UNITS_REMOVE_CONST(decltype(U))> tebi;
+template<PrefixableUnit auto U> inline constexpr pebi_<MP_UNITS_REMOVE_CONST(decltype(U))> pebi;
+template<PrefixableUnit auto U> inline constexpr exbi_<MP_UNITS_REMOVE_CONST(decltype(U))> exbi;
+template<PrefixableUnit auto U> inline constexpr zebi_<MP_UNITS_REMOVE_CONST(decltype(U))> zebi;
+template<PrefixableUnit auto U> inline constexpr yobi_<MP_UNITS_REMOVE_CONST(decltype(U))> yobi;
 // clang-format on
 
 MP_UNITS_EXPORT_END
diff --git a/src/systems/include/mp-units/systems/si/prefixes.h b/src/systems/include/mp-units/systems/si/prefixes.h
index fa7bbf1f..0aac147b 100644
--- a/src/systems/include/mp-units/systems/si/prefixes.h
+++ b/src/systems/include/mp-units/systems/si/prefixes.h
@@ -58,30 +58,30 @@ template<PrefixableUnit U> struct quetta_ : prefixed_unit<"Q", mag_power<10, 30>
 
 MP_UNITS_EXPORT_BEGIN
 
-template<PrefixableUnit auto U> inline constexpr quecto_<decltype(U)> quecto;
-template<PrefixableUnit auto U> inline constexpr ronto_<decltype(U)> ronto;
-template<PrefixableUnit auto U> inline constexpr yocto_<decltype(U)> yocto;
-template<PrefixableUnit auto U> inline constexpr zepto_<decltype(U)> zepto;
-template<PrefixableUnit auto U> inline constexpr atto_<decltype(U)> atto;
-template<PrefixableUnit auto U> inline constexpr femto_<decltype(U)> femto;
-template<PrefixableUnit auto U> inline constexpr pico_<decltype(U)> pico;
-template<PrefixableUnit auto U> inline constexpr nano_<decltype(U)> nano;
-template<PrefixableUnit auto U> inline constexpr micro_<decltype(U)> micro;
-template<PrefixableUnit auto U> inline constexpr milli_<decltype(U)> milli;
-template<PrefixableUnit auto U> inline constexpr centi_<decltype(U)> centi;
-template<PrefixableUnit auto U> inline constexpr deci_<decltype(U)> deci;
-template<PrefixableUnit auto U> inline constexpr deca_<decltype(U)> deca;
-template<PrefixableUnit auto U> inline constexpr hecto_<decltype(U)> hecto;
-template<PrefixableUnit auto U> inline constexpr kilo_<decltype(U)> kilo;
-template<PrefixableUnit auto U> inline constexpr mega_<decltype(U)> mega;
-template<PrefixableUnit auto U> inline constexpr giga_<decltype(U)> giga;
-template<PrefixableUnit auto U> inline constexpr tera_<decltype(U)> tera;
-template<PrefixableUnit auto U> inline constexpr peta_<decltype(U)> peta;
-template<PrefixableUnit auto U> inline constexpr exa_<decltype(U)> exa;
-template<PrefixableUnit auto U> inline constexpr zetta_<decltype(U)> zetta;
-template<PrefixableUnit auto U> inline constexpr yotta_<decltype(U)> yotta;
-template<PrefixableUnit auto U> inline constexpr ronna_<decltype(U)> ronna;
-template<PrefixableUnit auto U> inline constexpr quetta_<decltype(U)> quetta;
+template<PrefixableUnit auto U> inline constexpr quecto_<MP_UNITS_REMOVE_CONST(decltype(U))> quecto;
+template<PrefixableUnit auto U> inline constexpr ronto_<MP_UNITS_REMOVE_CONST(decltype(U))> ronto;
+template<PrefixableUnit auto U> inline constexpr yocto_<MP_UNITS_REMOVE_CONST(decltype(U))> yocto;
+template<PrefixableUnit auto U> inline constexpr zepto_<MP_UNITS_REMOVE_CONST(decltype(U))> zepto;
+template<PrefixableUnit auto U> inline constexpr atto_<MP_UNITS_REMOVE_CONST(decltype(U))> atto;
+template<PrefixableUnit auto U> inline constexpr femto_<MP_UNITS_REMOVE_CONST(decltype(U))> femto;
+template<PrefixableUnit auto U> inline constexpr pico_<MP_UNITS_REMOVE_CONST(decltype(U))> pico;
+template<PrefixableUnit auto U> inline constexpr nano_<MP_UNITS_REMOVE_CONST(decltype(U))> nano;
+template<PrefixableUnit auto U> inline constexpr micro_<MP_UNITS_REMOVE_CONST(decltype(U))> micro;
+template<PrefixableUnit auto U> inline constexpr milli_<MP_UNITS_REMOVE_CONST(decltype(U))> milli;
+template<PrefixableUnit auto U> inline constexpr centi_<MP_UNITS_REMOVE_CONST(decltype(U))> centi;
+template<PrefixableUnit auto U> inline constexpr deci_<MP_UNITS_REMOVE_CONST(decltype(U))> deci;
+template<PrefixableUnit auto U> inline constexpr deca_<MP_UNITS_REMOVE_CONST(decltype(U))> deca;
+template<PrefixableUnit auto U> inline constexpr hecto_<MP_UNITS_REMOVE_CONST(decltype(U))> hecto;
+template<PrefixableUnit auto U> inline constexpr kilo_<MP_UNITS_REMOVE_CONST(decltype(U))> kilo;
+template<PrefixableUnit auto U> inline constexpr mega_<MP_UNITS_REMOVE_CONST(decltype(U))> mega;
+template<PrefixableUnit auto U> inline constexpr giga_<MP_UNITS_REMOVE_CONST(decltype(U))> giga;
+template<PrefixableUnit auto U> inline constexpr tera_<MP_UNITS_REMOVE_CONST(decltype(U))> tera;
+template<PrefixableUnit auto U> inline constexpr peta_<MP_UNITS_REMOVE_CONST(decltype(U))> peta;
+template<PrefixableUnit auto U> inline constexpr exa_<MP_UNITS_REMOVE_CONST(decltype(U))> exa;
+template<PrefixableUnit auto U> inline constexpr zetta_<MP_UNITS_REMOVE_CONST(decltype(U))> zetta;
+template<PrefixableUnit auto U> inline constexpr yotta_<MP_UNITS_REMOVE_CONST(decltype(U))> yotta;
+template<PrefixableUnit auto U> inline constexpr ronna_<MP_UNITS_REMOVE_CONST(decltype(U))> ronna;
+template<PrefixableUnit auto U> inline constexpr quetta_<MP_UNITS_REMOVE_CONST(decltype(U))> quetta;
 // clang-format on
 
 MP_UNITS_EXPORT_END
diff --git a/test/static/test_tools.h b/test/static/test_tools.h
index bb98deb8..5fefba7b 100644
--- a/test/static/test_tools.h
+++ b/test/static/test_tools.h
@@ -27,7 +27,7 @@
 #include <type_traits>
 
 template<auto V, typename T>
-inline constexpr bool is_of_type = std::is_same_v<decltype(V), T>;
+inline constexpr bool is_of_type = std::is_same_v<MP_UNITS_REMOVE_CONST(decltype(V)), T>;
 
 // NOLINTBEGIN(cppcoreguidelines-macro-usage)
 #ifdef MP_UNITS_API_NO_CRTP