diff --git a/src/towncrier/_builder.py b/src/towncrier/_builder.py
index 7fc2a642..71f68e57 100644
--- a/src/towncrier/_builder.py
+++ b/src/towncrier/_builder.py
@@ -204,20 +204,45 @@ def find_fragments(
     return content, fragment_files
 
 
-def get_underline_length(text: str) -> int:
+def get_dict_length(obj: dict) -> int:
     """
-    Given `text` determine the underline length needed for the reStructuredText output.
+    Gets the sum of the underline lengths for all keys and values in a dictionary.
+    """
+    return sum(
+        get_underline_length(key) + get_underline_length(value)
+        for key, value in obj.items()
+    )
 
-    Particularly helps determine if an extra underline is needed for wide characters like emojis.
+
+def get_list_length(obj: list) -> int:
     """
-    underline_length: int = 0
-    for char in text:
-        if unicodedata.east_asian_width(char) in ("W", "F"):
-            underline_length += 2
-        else:
-            underline_length += 1
+    Gets the sum of the underline lengths for all items in a list.
+    """
+    return sum(get_underline_length(item) for item in obj)
+
+
+def get_string_length(text: str) -> int:
+    """
+    Determines the amount of characters needed to underline a string.
+    """
+    return sum(
+        2 if unicodedata.east_asian_width(char) in ("W", "F") else 1 for char in text
+    )
 
-    return underline_length
+
+def get_underline_length(obj: str | dict | list) -> int:
+    """
+    Given `obj` determine the underline length needed for the reStructuredText output.
+
+    Particularly helps determine if an extra underline is needed for wide characters like emojis.
+    """
+    if isinstance(obj, dict):
+        return get_dict_length(obj)
+    elif isinstance(obj, list):
+        return get_list_length(obj)
+    elif isinstance(obj, str):
+        return get_string_length(obj)
+    raise ValueError("Object must be a string, list, or dictionary.")
 
 
 def indent(text: str, prefix: str) -> str:
@@ -263,10 +288,6 @@ def split_fragments(
                 # it's recorded.
                 content = ""
 
-            definitions[category]["underline_length"] = get_underline_length(
-                definitions[category]["name"]
-            )
-
             texts = section.setdefault(category, {})
 
             issues = texts.setdefault(content, [])
@@ -432,9 +453,7 @@ def get_indent(text: str) -> str:
         top_underline=top_underline,
         get_indent=get_indent,  # simplify indentation in the jinja template.
         issues_by_category=issues_by_category,
-        versiondata_name_underline_length=get_underline_length(
-            versiondata.get("name", "")
-        ),
+        get_underline_length=get_underline_length,  # helps determine length for non-ascii chars
     )
 
     for line in res.split("\n"):
diff --git a/src/towncrier/templates/default.rst b/src/towncrier/templates/default.rst
index b40dfab1..9b196e79 100644
--- a/src/towncrier/templates/default.rst
+++ b/src/towncrier/templates/default.rst
@@ -1,29 +1,29 @@
 {% if render_title %}
 {% if versiondata.name %}
 {{ versiondata.name }} {{ versiondata.version }} ({{ versiondata.date }})
-{{ top_underline * ((versiondata.version + versiondata.date)|length + 4 + versiondata_name_underline_length)}}
+{{ top_underline * (get_underline_length(versiondata.name + versiondata.version + versiondata.date) + 4)}}
 {% else %}
 {{ versiondata.version }} ({{ versiondata.date }})
-{{ top_underline * ((versiondata.version + versiondata.date)|length + 3)}}
+{{ top_underline * (get_underline_length(versiondata.version + versiondata.date) + 3)}}
 {% endif %}
 {% endif %}
 {% for section, _ in sections.items() %}
 {% set underline = underlines[0] %}{% if section %}{{section}}
-{{ underline * section|length }}{% set underline = underlines[1] %}
+{{ underline * get_underline_length(section) }}{% set underline = underlines[1] %}
 
 {% endif %}
 
 {% if sections[section] %}
 {% for category, val in definitions.items() if category in sections[section]%}
 {{ definitions[category]['name'] }}
-{{ underline * definitions[category]['underline_length'] }}
+{{ underline * get_underline_length(definitions[category]['name']) }}
 
 {% for text, values in sections[section][category].items() %}
 - {% if text %}{{ text }}{% if values %} ({{ values|join(', ') }}){% endif %}{% else %}{{ values|join(', ') }}{% endif  %}
 
 {% endfor %}
 
-{% if sections[section][category]|length == 0 %}
+{% if get_underline_length(sections[section][category]) == 0 %}
 No significant changes.
 
 {% else %}
diff --git a/src/towncrier/templates/hr-between-versions.rst b/src/towncrier/templates/hr-between-versions.rst
index df95e91c..675196e0 100644
--- a/src/towncrier/templates/hr-between-versions.rst
+++ b/src/towncrier/templates/hr-between-versions.rst
@@ -1,22 +1,22 @@
 {% if render_title %}
 {% if versiondata.name %}
 {{ versiondata.name }} {{ versiondata.version }} ({{ versiondata.date }})
-{{ top_underline * ((versiondata.version + versiondata.date)|length + 4 + versiondata_name_underline_length)}}
+{{ top_underline * (get_underline_length(versiondata.name + versiondata.version + versiondata.date) + 4)}}
 {% else %}
 {{ versiondata.version }} ({{ versiondata.date }})
-{{ top_underline * ((versiondata.version + versiondata.date)|length + 3)}}
+{{ top_underline * (get_underline_length(versiondata.version + versiondata.date) + 3)}}
 {% endif %}
 {% endif %}
 {% for section, _ in sections.items() %}
 {% set underline = underlines[0] %}{% if section %}{{section}}
-{{ underline * section|length }}{% set underline = underlines[1] %}
+{{ underline * get_underline_length(section) }}{% set underline = underlines[1] %}
 
 {% endif %}
 
 {% if sections[section] %}
 {% for category, val in definitions.items() if category in sections[section]%}
 {{ definitions[category]['name'] }}
-{{ underline * definitions[category]['underline_length'] }}
+{{ underline * get_underline_length(definitions[category]['name']) }}
 
 {% if definitions[category]['showcontent'] %}
 {% for text, values in sections[section][category].items() %}
@@ -28,7 +28,7 @@
 - {{ sections[section][category]['']|join(', ') }}
 
 {% endif %}
-{% if sections[section][category]|length == 0 %}
+{% if get_underline_length(sections[section][category]) == 0 %}
 No significant changes.
 
 {% else %}
diff --git a/src/towncrier/templates/single-file-no-bullets.rst b/src/towncrier/templates/single-file-no-bullets.rst
index 83af1a78..7fbc34d0 100644
--- a/src/towncrier/templates/single-file-no-bullets.rst
+++ b/src/towncrier/templates/single-file-no-bullets.rst
@@ -1,22 +1,22 @@
 {% if render_title %}
 {% if versiondata.name %}
 {{ versiondata.name }} {{ versiondata.version }} ({{ versiondata.date }})
-{{ top_underline * ((versiondata.version + versiondata.date)|length + 4 + versiondata_name_underline_length)}}
+{{ top_underline * (get_underline_length(versiondata.name + versiondata.version + versiondata.date) + 4)}}
 {% else %}
 {{ versiondata.version }} ({{ versiondata.date }})
-{{ top_underline * ((versiondata.version + versiondata.date)|length + 3)}}
+{{ top_underline * (get_underline_length(versiondata.version + versiondata.date) + 3)}}
 {% endif %}
 {% endif %}
 {% for section, _ in sections.items() %}
 {% set underline = underlines[0] %}{% if section %}{{section}}
-{{ underline * section|length }}{% set underline = underlines[1] %}
+{{ underline * get_underline_length(section) }}{% set underline = underlines[1] %}
 
 {% endif %}
 {% if sections[section] %}
 {% for category, val in definitions.items() if category in sections[section] %}
 
 {{ definitions[category]['name'] }}
-{{ underline * definitions[category]['underline_length'] }}
+{{ underline * get_underline_length(definitions[category]['name']) }}
 
 {% if definitions[category]['showcontent'] %}
 {% for text, values in sections[section][category].items() %}
@@ -28,7 +28,7 @@
 - {{ sections[section][category]['']|join(', ') }}
 
 {% endif %}
-{% if sections[section][category]|length == 0 %}
+{% if get_underline_length(sections[section][category]) == 0 %}
 No significant changes.
 
 {% else %}