diff --git a/libgnucash/app-utils/gnc-option-impl.cpp b/libgnucash/app-utils/gnc-option-impl.cpp
index 961769de7b..210ef99676 100644
--- a/libgnucash/app-utils/gnc-option-impl.cpp
+++ b/libgnucash/app-utils/gnc-option-impl.cpp
@@ -131,15 +131,6 @@ GncOptionDateValue::set_value(size_t index) noexcept
     m_period = m_period_set[index];
 }
 
-void
-GncOptionDateValue::set_default_value(size_t index) noexcept
-{
-    assert(!m_period_set.empty());
-    assert(index < m_period_set.size());
-    m_date = m_default_date = INT64_MAX;
-    m_period = m_default_period = m_period_set[index];
-}
-
 size_t
 GncOptionDateValue::permissible_value_index(const char* key) const noexcept
 {
diff --git a/libgnucash/app-utils/gnc-option-impl.hpp b/libgnucash/app-utils/gnc-option-impl.hpp
index 02f58c2127..4b2f84de3a 100644
--- a/libgnucash/app-utils/gnc-option-impl.hpp
+++ b/libgnucash/app-utils/gnc-option-impl.hpp
@@ -1108,7 +1108,6 @@ public:
             m_date = m_default_date = time;
         }
     }
-    void set_default_value(size_t index) noexcept;
     std::size_t num_permissible_values() const noexcept
     {
         return m_period_set.size();