diff --git a/src/core/include/mp-units/framework/unit.h b/src/core/include/mp-units/framework/unit.h
index e4a79f14..91658a34 100644
--- a/src/core/include/mp-units/framework/unit.h
+++ b/src/core/include/mp-units/framework/unit.h
@@ -859,18 +859,16 @@ constexpr Out unit_symbol_impl(Out out, const type_list<Nums...>& nums, const ty
     return unit_symbol_impl<CharT>(out, nums, fmt, false);
   } else {
     using enum unit_symbol_solidus;
-    if constexpr (sizeof...(Nums) > 0) {
-      out = unit_symbol_impl<CharT>(out, nums, fmt, false);
-    }
+    if constexpr (sizeof...(Nums) > 0) out = unit_symbol_impl<CharT>(out, nums, fmt, false);
 
     if (fmt.solidus == always || (fmt.solidus == one_denominator && sizeof...(Dens) == 1)) {
       if constexpr (sizeof...(Nums) == 0) *out++ = '1';
       *out++ = '/';
-    } else {
+      if (sizeof...(Dens) > 1) *out++ = '(';
+    } else if constexpr (sizeof...(Nums) > 0) {
       out = print_separator<CharT>(out, fmt);
     }
 
-    if (fmt.solidus == always && sizeof...(Dens) > 1) *out++ = '(';
     const bool negative_power = fmt.solidus == never || (fmt.solidus == one_denominator && sizeof...(Dens) > 1);
     out = unit_symbol_impl<CharT>(out, dens, fmt, negative_power);
     if (fmt.solidus == always && sizeof...(Dens) > 1) *out++ = ')';
diff --git a/test/static/unit_symbol_test.cpp b/test/static/unit_symbol_test.cpp
index f18b74e5..48b75510 100644
--- a/test/static/unit_symbol_test.cpp
+++ b/test/static/unit_symbol_test.cpp
@@ -175,6 +175,8 @@ static_assert(unit_symbol<usf{.solidus = never}>(kilogram * metre / square(secon
 static_assert(unit_symbol<usf{.encoding = ascii, .solidus = never}>(kilogram * metre / square(second)) == "kg m s^-2");
 static_assert(unit_symbol<usf{.solidus = never, .separator = half_high_dot}>(kilogram * metre / square(second)) ==
               "kg⋅m⋅s⁻²");
+static_assert(unit_symbol(one / metre / square(second)) == "m⁻¹ s⁻²");
+static_assert(unit_symbol<usf{.solidus = always}>(one / metre / square(second)) == "1/(m s²)");
 static_assert(unit_symbol(kilogram / metre / square(second)) == "kg m⁻¹ s⁻²");
 static_assert(unit_symbol<usf{.separator = half_high_dot}>(kilogram / metre / square(second)) == "kg⋅m⁻¹⋅s⁻²");
 static_assert(unit_symbol<usf{.encoding = ascii}>(kilogram / metre / square(second)) == "kg m^-1 s^-2");