diff --git a/wp-includes/comment-template.php b/wp-includes/comment-template.php
index ca12ad7940..3714cbfc3c 100644
--- a/wp-includes/comment-template.php
+++ b/wp-includes/comment-template.php
@@ -2153,6 +2153,7 @@ function wp_list_comments( $args = array(), $comments = null ) {
  * in the array of fields.
  *
  * @since 3.0.0
+ * @since 4.2.0 Introduced 'submit_button' and 'submit_fields' arguments.
  *
  * @param array       $args {
  *     Optional. Default arguments and form fields to override.
@@ -2180,6 +2181,11 @@ function wp_list_comments( $args = array(), $comments = null ) {
  *                                        where %s is the author of the comment being replied to.
  *     @type string $cancel_reply_link    The translatable 'cancel reply' button label. Default 'Cancel reply'.
  *     @type string $label_submit         The translatable 'submit' button label. Default 'Post a comment'.
+ *     @type string $submit_button        HTML format for the Submit button.
+ *                                        Default: '<input name="%1$s" type="submit" id="%2$s" class="%3$s" value="%4$s" />'.
+ *     @type string $submit_field         HTML format for the markup surrounding the Submit button and comment hidden
+ *                                        fields. Default: '<p class="form-submit">%1$s %2$s</a>', where %1$s is the
+ *                                        submit button markup and %2$s is the comment hidden fields.
  *     @type string $format               The comment form format. Default 'xhtml'. Accepts 'xhtml', 'html5'.
  * }
  * @param int|WP_Post $post_id Post ID or WP_Post object to generate the form for. Default current post.
@@ -2236,6 +2242,8 @@ function comment_form( $args = array(), $post_id = null ) {
 		'title_reply_to'       => __( 'Leave a Reply to %s' ),
 		'cancel_reply_link'    => __( 'Cancel reply' ),
 		'label_submit'         => __( 'Post Comment' ),
+		'submit_button'        => '<input name="%1$s" type="submit" id="%2$s" class="%3$s" value="%4$s" />',
+		'submit_field'         => '<p class="form-submit">%1$s %2$s</p>',
 		'format'               => 'xhtml',
 	);
 
@@ -2350,11 +2358,45 @@ function comment_form( $args = array(), $post_id = null ) {
 						echo apply_filters( 'comment_form_field_comment', $args['comment_field'] );
 						?>
 						<?php echo $args['comment_notes_after']; ?>
-						<p class="form-submit">
-							<input name="<?php echo esc_attr( $args['name_submit'] ); ?>" type="submit" id="<?php echo esc_attr( $args['id_submit'] ); ?>" class="<?php echo esc_attr( $args['class_submit'] ); ?>" value="<?php echo esc_attr( $args['label_submit'] ); ?>" />
-							<?php comment_id_fields( $post_id ); ?>
-						</p>
+
 						<?php
+						$submit_button = sprintf(
+							$args['submit_button'],
+							esc_attr( $args['name_submit'] ),
+							esc_attr( $args['id_submit'] ),
+							esc_attr( $args['class_submit'] ),
+							esc_attr( $args['label_submit'] )
+						);
+
+						/**
+						 * Filter the submit button for the comment form to display.
+						 *
+						 * @since 4.2.0
+						 *
+						 * @param string $submit_button HTML markup for the submit button.
+						 * @param array  $args          Arguments passed to `comment_form()`.
+						 */
+						$submit_button = apply_filters( 'comment_form_submit_button', $submit_button, $args );
+
+						$submit_field = sprintf(
+							$args['submit_field'],
+							$submit_button,
+							get_comment_id_fields( $post_id )
+						);
+
+						/**
+						 * Filter the submit field for the comment form to display.
+						 *
+						 * The submit field includes the submit button, hidden fields for the
+						 * comment form, and any wrapper markup.
+						 *
+						 * @since 4.2.0
+						 *
+						 * @param string $submit_field HTML markup for the submit field.
+						 * @param array  $args         Arguments passed to `comment_form()`.
+						 */
+						echo apply_filters( 'comment_form_submit_field', $submit_field, $args );
+
 						/**
 						 * Fires at the bottom of the comment form, inside the closing </form> tag.
 						 *
diff --git a/wp-includes/version.php b/wp-includes/version.php
index f1e228d1cb..97d291e03b 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.2-alpha-31698';
+$wp_version = '4.2-alpha-31699';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.