Key points: Required fields have two separate layers: the indicator and the enforcement. Asterisks can display even when empty submissions still go

Required fields in WordPress consist of two independent systems: visual indicators (asterisks) and enforcement logic. The asterisk alone does nothing to block empty submissions. Client-side JavaScript validation can be bypassed or silently broken by JS errors, caching plugins, or plugin conflicts. Server-side PHP validation is the only reliable enforcement. The post covers how form builders (Gravity Forms, WPForms, Ninja Forms, Contact Form 7), registration plugins, and publishing workflow plugins handle required fields, and explains how Advanced Custom Fields (ACF) provides non-bypassable server-side validation with conditional logic across admin screens, frontend forms, and REST API requests. Common failure scenarios are diagnosed, including missing acf_form_head() calls, max_input_vars limits, and caching issues.

WordPress Required Fields: What’s Really Happening Under the Hood

Setting required fields in publishing workflows

Using ACF for server-side required field enforcement

Diagnosing common required field failures

Move beyond asterisks with ACF’s required field validation