diff --git a/CHANGELOG.md b/CHANGELOG.md
index b09c39e6..f03fcf81 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,6 +12,7 @@
 - Auto scroll sticky ToC with content. [#3115](https://github.com/mmistakes/minimal-mistakes/pull/3115)
 - Replace "hidden" check in Liquid templates with `where_exp: "item", "item.hidden != true"`.
 - Remove deprecated `page.header.cta_url` setting. [#4821](https://github.com/mmistakes/minimal-mistakes/pull/4821)
+- Merge `categories` and `tags` layout into `_includes/posts-taxonomy.html`.
 
 ### Documentation & Maintenance
 
diff --git a/_includes/posts-taxonomy.html b/_includes/posts-taxonomy.html
new file mode 100644
index 00000000..e99db65c
--- /dev/null
+++ b/_includes/posts-taxonomy.html
@@ -0,0 +1,37 @@
+{% assign items_max = 0 %}
+{% for item in include.taxonomies %}
+  {% if item[1].size > items_max %}
+    {% assign items_max = item[1].size %}
+  {% endif %}
+{% endfor %}
+
+<ul class="taxonomy__index">
+  {% for i in (1..items_max) reversed %}
+    {% for item in include.taxonomies %}
+      {% if item[1].size == i %}
+        <li>
+          <a href="#{{ item[0] | slugify }}">
+            <strong>{{ item[0] }}</strong> <span class="taxonomy__count">{{ i }}</span>
+          </a>
+        </li>
+      {% endif %}
+    {% endfor %}
+  {% endfor %}
+</ul>
+
+{% assign entries_layout = page.entries_layout | default: 'list' %}
+{% for i in (1..items_max) reversed %}
+  {% for taxonomy in include.taxonomies %}
+    {% if taxonomy[1].size == i %}
+      <section id="{{ taxonomy[0] | slugify }}" class="taxonomy__section">
+        <h2 class="archive__subtitle">{{ taxonomy[0] }}</h2>
+        <div class="entries-{{ entries_layout }}">
+          {% for post in taxonomy.last %}
+            {% include archive-single.html type=entries_layout %}
+          {% endfor %}
+        </div>
+        <a href="#page-title" class="back-to-top">{{ site.data.ui-text[site.locale].back_to_top | default: 'Back to Top' }} &uarr;</a>
+      </section>
+    {% endif %}
+  {% endfor %}
+{% endfor %}
diff --git a/_layouts/categories.html b/_layouts/categories.html
index ec9a6980..4d366118 100644
--- a/_layouts/categories.html
+++ b/_layouts/categories.html
@@ -4,40 +4,4 @@ layout: archive
 
 {{ content }}
 
-{% assign categories_max = 0 %}
-{% for category in site.categories %}
-  {% if category[1].size > categories_max %}
-    {% assign categories_max = category[1].size %}
-  {% endif %}
-{% endfor %}
-
-<ul class="taxonomy__index">
-  {% for i in (1..categories_max) reversed %}
-    {% for category in site.categories %}
-      {% if category[1].size == i %}
-        <li>
-          <a href="#{{ category[0] | slugify }}">
-            <strong>{{ category[0] }}</strong> <span class="taxonomy__count">{{ i }}</span>
-          </a>
-        </li>
-      {% endif %}
-    {% endfor %}
-  {% endfor %}
-</ul>
-
-{% assign entries_layout = page.entries_layout | default: 'list' %}
-{% for i in (1..categories_max) reversed %}
-  {% for category in site.categories %}
-    {% if category[1].size == i %}
-      <section id="{{ category[0] | slugify }}" class="taxonomy__section">
-        <h2 class="archive__subtitle">{{ category[0] }}</h2>
-        <div class="entries-{{ entries_layout }}">
-          {% for post in category.last %}
-            {% include archive-single.html type=entries_layout %}
-          {% endfor %}
-        </div>
-        <a href="#page-title" class="back-to-top">{{ site.data.ui-text[site.locale].back_to_top | default: 'Back to Top' }} &uarr;</a>
-      </section>
-    {% endif %}
-  {% endfor %}
-{% endfor %}
+{% include posts-taxonomy.html taxonomies=site.categories %}
diff --git a/_layouts/tags.html b/_layouts/tags.html
index daa11828..a28fa5d7 100644
--- a/_layouts/tags.html
+++ b/_layouts/tags.html
@@ -4,40 +4,4 @@ layout: archive
 
 {{ content }}
 
-{% assign tags_max = 0 %}
-{% for tag in site.tags %}
-  {% if tag[1].size > tags_max %}
-    {% assign tags_max = tag[1].size %}
-  {% endif %}
-{% endfor %}
-
-<ul class="taxonomy__index">
-  {% for i in (1..tags_max) reversed %}
-    {% for tag in site.tags %}
-      {% if tag[1].size == i %}
-        <li>
-          <a href="#{{ tag[0] | slugify }}">
-            <strong>{{ tag[0] }}</strong> <span class="taxonomy__count">{{ i }}</span>
-          </a>
-        </li>
-      {% endif %}
-    {% endfor %}
-  {% endfor %}
-</ul>
-
-{% assign entries_layout = page.entries_layout | default: 'list' %}
-{% for i in (1..tags_max) reversed %}
-  {% for tag in site.tags %}
-    {% if tag[1].size == i %}
-      <section id="{{ tag[0] | slugify | downcase }}" class="taxonomy__section">
-        <h2 class="archive__subtitle">{{ tag[0] }}</h2>
-        <div class="entries-{{ entries_layout }}">
-          {% for post in tag.last %}
-            {% include archive-single.html type=entries_layout %}
-          {% endfor %}
-        </div>
-        <a href="#page-title" class="back-to-top">{{ site.data.ui-text[site.locale].back_to_top | default: 'Back to Top' }} &uarr;</a>
-      </section>
-    {% endif %}
-  {% endfor %}
-{% endfor %}
+{% include posts-taxonomy.html taxonomies=site.tags %}
diff --git a/docs/_docs/18-history.md b/docs/_docs/18-history.md
index 2f746169..08d8ab35 100644
--- a/docs/_docs/18-history.md
+++ b/docs/_docs/18-history.md
@@ -5,7 +5,7 @@ permalink: "/docs/history/"
 excerpt: Change log of enhancements and bug fixes made to the theme.
 sidebar:
   nav: docs
-last_modified_at: '2024-05-05T05:53:36+08:00'
+last_modified_at: '2024-05-05T14:13:21+08:00'
 toc: false
 ---
 
@@ -27,6 +27,7 @@ toc: false
 - Auto scroll sticky ToC with content. [#3115](https://github.com/mmistakes/minimal-mistakes/pull/3115)
 - Replace "hidden" check in Liquid templates with `where_exp: "item", "item.hidden != true"`.
 - Remove deprecated `page.header.cta_url` setting. [#4821](https://github.com/mmistakes/minimal-mistakes/pull/4821)
+- Merge `categories` and `tags` layout into `_includes/posts-taxonomy.html`.
 
 ### Documentation & Maintenance