diff --git a/assets/styles/components/forms.css b/assets/styles/components/forms.css
index c607a36..f4a34f5 100644
--- a/assets/styles/components/forms.css
+++ b/assets/styles/components/forms.css
@@ -21,7 +21,7 @@ label.required:after {
     @apply border-red-500;
 }
 
-input[disabled],
-input[readonly] {
-    @apply cursor-not-allowed;
+input[readonly],
+select[readonly] {
+    @apply pointer-events-none;
 }
diff --git a/src/Form/ParticipantType.php b/src/Form/ParticipantType.php
index 4870b05..ea288d9 100644
--- a/src/Form/ParticipantType.php
+++ b/src/Form/ParticipantType.php
@@ -149,7 +149,7 @@ class ParticipantType extends AbstractType
                         number_format($price, 2, ',', '.')
                     );
                 },
-                'choice_attr' => function (?Service $service) {
+                'choice_attr' => function (?Service $service) use ($options) {
                     $attributes = [
                         'data-booking-target' => 'field',
                         'data-action' => 'booking#toggle',
@@ -158,24 +158,28 @@ class ParticipantType extends AbstractType
                     // forcibly select mandatory services
                     if (true === $service->mandatory) {
                         $attributes['checked'] = true;
-                        $attributes['disabled'] = true;
+                        $attributes['readonly'] = true;
                         $attributes['class'] = 'text-pink';
                         $attributes['tooltip'] = 'Diese Leistung ist nicht abwählbar';
                     }
 
                     // disable selection of services only available in booking data
                     if (Service::SOURCE_BOOKING === $service->source) {
-                        $attributes['disabled'] = true;
                         $attributes['class'] = 'text-pink';
                     }
 
                     // disable selection of services that are unavailable according to their status
                     if (Service::STATUS_BLOCKED === $service->status) {
                         $attributes['checked'] = false;
-                        $attributes['disabled'] = true;
+                        $attributes['readonly'] = true;
                         $attributes['tooltip'] = 'Diese Leistung ist derzeit leider nicht buchbar';
                     }
 
+                    if (false === $options['additional_services_mutable']) {
+                        $attributes['readonly'] = true;
+                        $attributes['tooltip'] = 'Diese Leistung kann nicht mehr geändert werden';
+                    }
+
                     return $attributes;
                 },
                 'choice_filter' => function (?Service $service) use ($participantData) {
@@ -233,6 +237,19 @@ class ParticipantType extends AbstractType
             }
 
             // Transportation
+            $transportationChoiceAttributes = function (?Service $service) use ($options) {
+                $attributes = [
+                    'data-booking-target' => 'field',
+                    'data-action' => 'select-toggle#toggle booking#toggle',
+                    'data-select-toggle-value' => $service->subType,
+                ];
+                if (false === $options['transportation_services_mutable']) {
+                    $attributes['readonly'] = true;
+                    $attributes['tooltip'] = 'Diese Leistung kann nicht mehr geändert werden';
+                }
+
+                return $attributes;
+            };
             $form
                 ->add('transportationServiceTo', ChoiceType::class, [
                     ...$commonChoiceFieldOptions,
@@ -240,13 +257,7 @@ class ParticipantType extends AbstractType
                     'required' => true,
                     'multiple' => false,
                     'choices' => $options['selectable_transportation_services_to'],
-                    'choice_attr' => function (?Service $service) {
-                        return [
-                            'data-booking-target' => 'field',
-                            'data-action' => 'select-toggle#toggle booking#toggle',
-                            'data-select-toggle-value' => $service->subType,
-                        ];
-                    },
+                    'choice_attr' => $transportationChoiceAttributes,
                 ])
                 ->add('transportationServiceFro', ChoiceType::class, [
                     ...$commonChoiceFieldOptions,
@@ -254,13 +265,7 @@ class ParticipantType extends AbstractType
                     'required' => true,
                     'multiple' => false,
                     'choices' => $options['selectable_transportation_services_fro'],
-                    'choice_attr' => function (?Service $service) {
-                        return [
-                            'data-booking-target' => 'field',
-                            'data-action' => 'select-toggle#toggle booking#toggle',
-                            'data-select-toggle-value' => $service->subType,
-                        ];
-                    },
+                    'choice_attr' => $transportationChoiceAttributes,
                 ])
             ;
 
@@ -287,6 +292,17 @@ class ParticipantType extends AbstractType
                         number_format($price, 2, ',', '.')
                     );
                 },
+                'choice_attr' => function (?Pickup $pickup) use ($options) {
+                    $attributes = [];
+                    if (false === $options['pickups_mutable']) {
+                        $attributes['readonly'] = true;
+                    }
+
+                    return $attributes;
+                },
+                'attr' => [
+                    'readonly' => false === $options['pickups_mutable'],
+                ]
             ]);
         })
         ->addEventListener(FormEvents::PRE_SUBMIT, function (FormEvent $event) use ($options) {
diff --git a/templates/forms.html.twig b/templates/forms.html.twig
index 0f63102..b15fd66 100644
--- a/templates/forms.html.twig
+++ b/templates/forms.html.twig
@@ -69,9 +69,6 @@
     {%- if errors|length -%}
         {%- set attr = attr|merge({'class': attr.class|default('') ~ ' form-checkbox--has-error' }) -%}
     {%- endif -%}
-    {%- if attr.disabled is defined and attr.disabled == true -%}
-        {%- set attr = attr|merge({'class': attr.class|default('') ~ ' cursor-not-allowed' }) -%}
-    {%- endif -%}
     {%- set tooltip = null -%}
     {%- if attr.tooltip is defined -%}
         {%- set tooltip = attr.tooltip -%}
@@ -87,9 +84,6 @@
     {%- if errors|length -%}
         {%- set attr = attr|merge({'class': attr.class|default('') ~ ' form-radio--has-error' }) -%}
     {%- endif -%}
-    {%- if attr.disabled is defined and attr.disabled == true -%}
-        {%- set attr = attr|merge({'class': attr.class|default('') ~ ' cursor-not-allowed' }) -%}
-    {%- endif -%}
     {%- set tooltip = null -%}
     {%- if attr.tooltip is defined -%}
         {%- set tooltip = attr.tooltip -%}
@@ -101,7 +95,7 @@
 {%- endblock radio_widget -%}
 
 {% block checkbox_row %}
-    <div class="relative flex items-start">
+    <div class="{{ html_classes('relative flex items-start', { 'cursor-not-allowed': form.vars.attr.readonly is defined }) }}">
         <div class="flex h-6 items-center">
             {{ form_widget(form) }}
         </div>
@@ -129,9 +123,6 @@
     {% else %}
         {{ parent() }}
     {% endif %}
-    {%- if disabled is defined and disabled == true -%}
-        <input type="hidden" name="{{ form.vars.full_name }}" value="{{ form.vars.value }}">
-    {%- endif -%}
 {%- endblock choice_widget_collapsed -%}
 
 {%- block choice_widget_expanded -%}