# Block Contact Form 7 Messages Containing Spam Words

> Marks Contact Form 7 submissions as spam when any field contains a word or phrase from your block list, such as SEO offers or crypto pitches.

- Type: PHP
- Runs: Run everywhere
- Category: [Forms](https://wpide.com/library/category/forms/)
- Tags: contact-form-7, spam, blocklist
- Author: WPIDE Team
- Installs: 0
- Updated: 2026-10-28
- Page: https://wpide.com/library/cf7-blocked-words/

## Code

```php
// Words and phrases that mark a submission as spam.
$wpide_cf7_blocked_words = array( 'seo services', 'backlinks', 'crypto', 'casino', 'guest post', 'rank your website', 'viagra' );

add_filter( 'wpcf7_spam', function ( $spam, $submission = null ) use ( $wpide_cf7_blocked_words ) {
    if ( $spam || ! $submission || ! $wpide_cf7_blocked_words ) {
        return $spam;
    }

    $text = '';
    foreach ( (array) $submission->get_posted_data() as $value ) {
        $text .= ' ' . ( is_array( $value ) ? implode( ' ', $value ) : (string) $value );
    }

    foreach ( $wpide_cf7_blocked_words as $word ) {
        if ( preg_match( '/\b' . preg_quote( $word, '/' ) . '\b/iu', $text ) ) {
            $submission->add_spam_log( array( 'agent' => 'wpide-blocked-words', 'reason' => sprintf( 'Contains "%s".', $word ) ) );
            return true;
        }
    }

    return false;
}, 10, 2 );
```

## Notes

Matching is case-insensitive on whole words; add phrases you keep receiving to the list.

## How to use it

Install the free WPIDE plugin (https://wordpress.org/plugins/wpide/), find "Block Contact Form 7 Messages Containing Spam Words" in its snippet library and add it in one click; or create a new PHP snippet in WPIDE (or any code snippets plugin) and paste the code above. More snippets: https://wpide.com/library/