diff --git a/apps/portal/src/pages/register/[public_token].vue b/apps/portal/src/pages/register/[public_token].vue
index 96d33ad4..ea9159d3 100644
--- a/apps/portal/src/pages/register/[public_token].vue
+++ b/apps/portal/src/pages/register/[public_token].vue
@@ -442,6 +442,7 @@ function formatReviewValue(field: PublicFormField): string {
               v-if="currentStep > 0"
               variant="outlined"
               color="secondary"
+              class="form-btn-sentence-case"
               @click="prevStep"
             >
               <VIcon
@@ -457,6 +458,7 @@ function formatReviewValue(field: PublicFormField): string {
                 v-if="activeStep && activeStep.kind !== 'review'"
                 variant="text"
                 color="primary"
+                class="form-btn-sentence-case"
                 :loading="draft.isSaving.value"
                 :disabled="!draft.submission.value"
                 @click="onSaveDraft"
@@ -467,6 +469,7 @@ function formatReviewValue(field: PublicFormField): string {
               <VBtn
                 v-if="currentStep < steps.length - 1"
                 color="primary"
+                class="form-btn-sentence-case"
                 :disabled="!isActiveStepValid"
                 @click="nextStep"
               >
@@ -480,6 +483,7 @@ function formatReviewValue(field: PublicFormField): string {
               <VBtn
                 v-else
                 color="success"
+                class="form-btn-sentence-case"
                 :loading="draft.isSubmitting.value"
                 @click="onSubmit"
               >
@@ -532,4 +536,10 @@ function formatReviewValue(field: PublicFormField): string {
 .public-form-page {
   min-block-size: 100dvh;
 }
+
+/* Portal theme capitalizes VBtn labels by default; this page uses
+   sentence-case Dutch labels ("Sla op als concept", not title-case). */
+.form-btn-sentence-case {
+  text-transform: none !important;
+}
 </style>