Index: src/wp-includes/general-template.php
===================================================================
--- src/wp-includes/general-template.php	(revision 25950)
+++ src/wp-includes/general-template.php	(working copy)
@@ -2027,9 +2027,8 @@
 		$page_links[] = '<a class="prev page-numbers" href="' . esc_url( apply_filters( 'paginate_links', $link ) ) . '">' . $prev_text . '</a>';
 	endif;
 	for ( $n = 1; $n <= $total; $n++ ) :
-		$n_display = number_format_i18n($n);
 		if ( $n == $current ) :
-			$page_links[] = "<span class='page-numbers current'>$n_display</span>";
+			$page_links[] = "<span class='page-numbers current'>" . number_format_i18n($n) . "</span>";
 			$dots = true;
 		else :
 			if ( $show_all || ( $n <= $end_size || ( $current && $n >= $current - $mid_size && $n <= $current + $mid_size ) || $n > $total - $end_size ) ) :
@@ -2038,7 +2037,7 @@
 				if ( $add_args )
 					$link = add_query_arg( $add_args, $link );
 				$link .= $add_fragment;
-				$page_links[] = "<a class='page-numbers' href='" . esc_url( apply_filters( 'paginate_links', $link ) ) . "'>$n_display</a>";
+				$page_links[] = "<a class='page-numbers' href='" . esc_url( apply_filters( 'paginate_links', $link ) ) . "'>" . number_format_i18n($n) . "</a>";
 				$dots = true;
 			elseif ( $dots && !$show_all ) :
 				$page_links[] = '<span class="page-numbers dots">' . __( '&hellip;' ) . '</span>';
Index: tests/phpunit/tests/general/template.php
===================================================================
--- tests/phpunit/tests/general/template.php	(revision 0)
+++ tests/phpunit/tests/general/template.php	(working copy)
@@ -0,0 +1,31 @@
+<?php
+
+class Tests_General_Template extends WP_UnitTestCase {
+
+	private $i18n_count = 0;
+
+	function increment_i18n_count() {
+		$this->i18n_count += 1;
+	}
+
+	/**
+	 * @ticket 25735
+	 */
+	function test_paginate_links_number_format() {
+		$this->i18n_count = 0;
+		add_filter( 'number_format_i18n', array( $this, 'increment_i18n_count' ) );
+		paginate_links( array(
+			'total'     => 100,
+			'current'   => 50,
+			'show_all'  => false,
+			'prev_next' => true,
+			'end_size'  => 1,
+			'mid_size'  => 1,
+		) );
+		// The links should be:
+		// < Previous 1 ... 49 50 51 ... 100 Next >
+		$this->assertEquals( 5, $this->i18n_count );
+		remove_filter( 'number_format_i18n', array( $this, 'increment_i18n_count' ) );
+	}
+
+}