diff --git a/include/fmt/base.h b/include/fmt/base.h
index 7b678d7d..2700e631 100644
--- a/include/fmt/base.h
+++ b/include/fmt/base.h
@@ -2627,18 +2627,20 @@ class context : private detail::locale_ref {
   void operator=(const context&) = delete;
 
   FMT_CONSTEXPR auto arg(int id) const -> format_arg { return args_.get(id); }
-  inline auto arg(string_view name) -> format_arg { return args_.get(name); }
-  FMT_CONSTEXPR auto arg_id(string_view name) -> int {
+  inline auto arg(string_view name) const -> format_arg {
+    return args_.get(name);
+  }
+  FMT_CONSTEXPR auto arg_id(string_view name) const -> int {
     return args_.get_id(name);
   }
 
   // Returns an iterator to the beginning of the output range.
-  FMT_CONSTEXPR auto out() -> iterator { return out_; }
+  FMT_CONSTEXPR auto out() const -> iterator { return out_; }
 
   // Advances the begin iterator to `it`.
   FMT_CONSTEXPR void advance_to(iterator) {}
 
-  FMT_CONSTEXPR auto locale() -> detail::locale_ref { return *this; }
+  FMT_CONSTEXPR auto locale() const -> detail::locale_ref { return *this; }
 };
 
 template <typename Char = char> struct runtime_format_string {
diff --git a/include/fmt/format.h b/include/fmt/format.h
index a8091cbf..6c729a60 100644
--- a/include/fmt/format.h
+++ b/include/fmt/format.h
@@ -3708,20 +3708,21 @@ template <typename OutputIt, typename Char> class generic_context {
   constexpr auto arg(int id) const -> basic_format_arg<generic_context> {
     return args_.get(id);
   }
-  auto arg(basic_string_view<Char> name) -> basic_format_arg<generic_context> {
+  auto arg(basic_string_view<Char> name) const
+      -> basic_format_arg<generic_context> {
     return args_.get(name);
   }
-  FMT_CONSTEXPR auto arg_id(basic_string_view<Char> name) -> int {
+  constexpr auto arg_id(basic_string_view<Char> name) const -> int {
     return args_.get_id(name);
   }
 
-  FMT_CONSTEXPR auto out() -> iterator { return out_; }
+  constexpr auto out() const -> iterator { return out_; }
 
   void advance_to(iterator it) {
     if (!detail::is_back_insert_iterator<iterator>()) out_ = it;
   }
 
-  FMT_CONSTEXPR auto locale() -> detail::locale_ref { return loc_; }
+  constexpr auto locale() const -> detail::locale_ref { return loc_; }
 };
 
 class loc_value {