diff --git a/sipa/templates/base.html b/sipa/templates/base.html
index d2aa92c8..b689c57f 100644
--- a/sipa/templates/base.html
+++ b/sipa/templates/base.html
@@ -137,7 +137,7 @@
                 class="navbar-nav ms-auto d-xs-none d-lg-block d-xl-none">
                 <li class="nav-item dropdown">
                     <button id="language-dropdown-button" type="button"
-                            class="btn btn-default navbar-btn"
+                            class="btn btn-secondary navbar-btn"
                             data-bs-toggle="dropdown" aria-label="Toggle Menu" aria-expanded="false">
                         <span class="bi-gear-fill" aria-hidden="true"></span>
                     </button>
diff --git a/sipa/templates/macros/forms.html b/sipa/templates/macros/forms.html
index af27ff27..8f61b48e 100644
--- a/sipa/templates/macros/forms.html
+++ b/sipa/templates/macros/forms.html
@@ -50,10 +50,10 @@
                 <div class="{{ form_input_offset_class }} {{ form_input_width_class }} text-nowrap">
                     <button type="submit" class="btn btn-primary">{{ submit_text }}</button>
                     {% if reset_button -%}
-                        <button type="reset" class="btn btn-default">{{ _('Zurücksetzen') }}</button>
+                        <button type="reset" class="btn btn-secondary">{{ _('Zurücksetzen') }}</button>
                     {%- endif %}
                     {% if cancel_to -%}
-                        <a href="{{ cancel_to }}" class="btn btn-default">{{ cancel_text }}</a>
+                        <a href="{{ cancel_to }}" class="btn btn-secondary">{{ cancel_text }}</a>
                     {%- endif %}
                     {% if extra_btn -%}{{ extra_btn() }}{%- endif %}
                 </div>
diff --git a/sipa/templates/usersuite/_index_status.html b/sipa/templates/usersuite/_index_status.html
index 25a7760f..ebdb7de2 100644
--- a/sipa/templates/usersuite/_index_status.html
+++ b/sipa/templates/usersuite/_index_status.html
@@ -1,12 +1,12 @@
 <h2 id="hot-buttons">{{ _("Häufige Aktionen") }}</h2>
 <div class="btn-group">
     {% if current_user.can_change_password %}
-    <a href="{{ url_for('.change_password') }}" class="btn btn-default">
+    <a href="{{ url_for('.change_password') }}" class="btn btn-outline-secondary">
         <span class="bi-asterisk"></span>
         {{ _("Passwort ändern") }}
     </a>
     {% else %}
-    <a class="btn btn-default" disabled title="{{ _('Nicht unterstützt') }}">
+    <a class="btn btn-secondary" disabled title="{{ _('Nicht unterstützt') }}">
         <span class="bi-pencil-fill"></span>
         {{ _("Passwort ändern") }}
     </a>
@@ -17,19 +17,19 @@ <h2 id="hot-buttons">{{ _("Häufige Aktionen") }}</h2>
         {{ _("Netzwerkanschluss aktivieren") }}
     </a>
     {% elif current_user.mac.capabilities.edit %}
-    <a href="{{ url_for('.change_mac') }}" class="btn btn-default">
+    <a href="{{ url_for('.change_mac') }}" class="btn btn-outline-secondary">
         <span class="bi-pencil-fill"></span>
         {{ _("MAC-Adresse ändern") }}
     </a>
     {% else %}
-    <a class="btn btn-default" disabled title="{{ _('Nicht unterstützt') }}">
+    <a class="btn btn-outline-secondary" disabled title="{{ _('Nicht unterstützt') }}">
         <span class="bi-pencil-fill"></span>
         {{ _("MAC-Adresse ändern") }}
     </a>
     {% endif %}
 
     {% if webmailer_url %}
-    <a href="{{ webmailer_url }}" class="btn btn-default">
+    <a href="{{ webmailer_url }}" class="btn btn-outline-secondary">
         <span class="bi-envelope-fill"></span>
         {{ _("Webmailer") }}
     </a>
@@ -49,11 +49,11 @@ <h2 id="hot-buttons">{{ _("Häufige Aktionen") }}</h2>
     {% endif %}
 </div>
 <div class="btn-group">
-    <a href="{{ url_for('.contact') }}" class="btn btn-default">
+    <a href="{{ url_for('.contact') }}" class="btn btn-outline-secondary">
         <span class="bi-question-circle-fill"></span>
         {{ _("Kontaktformular") }}
     </a>
-    <a href="{{ url_for('.subscribe') }}" class="btn btn-default">
+    <a href="{{ url_for('.subscribe') }}" class="btn btn-outline-secondary">
         <span class="bi-megaphone-fill"></span>
         {{ _("Status-Page abonnieren") }}
     </a>
diff --git a/sipa/templates/usersuite/_payment_details.html b/sipa/templates/usersuite/_payment_details.html
index 65dd4fbf..6e61f347 100644
--- a/sipa/templates/usersuite/_payment_details.html
+++ b/sipa/templates/usersuite/_payment_details.html
@@ -6,7 +6,7 @@ <h2 id="payment-details">{{ _("Zahlungsdetails") }}</h2>
     <div class="input-group">
         {{ payment_form.months(class_="form-control", size="2", **{'aria-label': _("Monate")}) }}
         <span class="input-group-btn">
-            <button type="submit" class="btn btn-default">{{ _("Aktualisieren") }}</button>
+            <button type="submit" class="btn btn-secondary">{{ _("Aktualisieren") }}</button>
         </span>
     </div>
     {{ _("Monat(e) zahlen.") }}