Here is the list of 26 best free social media plugins for WordPress:
WP to Twitter: Posts a Twitter update when you update your WordPress blog or add a link, with your chosen URL shortening service.
Add Link to Facebook: Automatically add links to published posts or pages to your Facebook wall, pages, or groups and more.
Xhanch – My Twitter: The best plugin to display your latest tweets, replies, direct messages, retweets, auto and manual tweet and lots more. Support multiple accounts.
Facebook Like Button: Add the new Facebook Like button and Facebook Recommendations widget to your WordPress blog.
Social Media Feather: Super lightweight, simple, nice, modern looking, and effective social media sharing, following buttons, and icons. Add on your site quick and easy.
Floating Social Media Icon: Easy to use a plugin to show social media icons floating. Can configure social icon design, order, and size. Supports widget and shortcodes.
Also Read: Best Free SEO Plugins for WordPress
Facebook Like Box Widget: Facebook Like Box Widget is a social plugin that enables Facebook Page owners to attract and gain Likes from their own website.
Social Media Widget: Social media widget plugin. A simple social icon widget to show essential social media icons. Can configure social icon design, order, and size.
Simple Social Buttons: Insert and customize social buttons: Facebook (Like it), Google+, Twitter share, and Pinterest (Pin it). Share your content with friends.
Recent Tweets Widget: Recent Tweets Widget plugin for new Twitter API v1.1 with cache, so you won’t be rate limited at Twitter!
Simple Social Icons: This plugin allows you to insert social icons in any widget area.
Social Media Tabs: Social media tabs allows you to add Facebook, Google+, twitter, Flickr, Pinterest, YouTube subscription, and RSS profiles and feeds to any widget.
Social Slider: This plugin adds links to your social networking sites’ profiles in a box floating at the left side of the screen.
The Google+ plugin: The Google + Plugin integrates WordPress with your Google+ Profile and Page – now with BuddyPress and Post Format Support!
Facebook Page Promoter Lightbox: All your visitors should know about your Facebook page to tell their friends. With this plugin, you can display a preconfigured Facebook Fan Page-Like.
Facebook Members: The simplest way to bring Facebook LikeBox + Facebook recommendation bar functionality to WordPress with many more options.
Kebo Twitter Feed: Display your Twitter Feed beautifully in 60 seconds.
IK Facebook Plugin: IK Facebook is an easy-to-use plugin for adding a custom Facebook feed of any public Facebook page to your site with a shortcode or widget.
Rotating Tweets (Twitter widget and shortcode): Twitter widget and shortcode to show your latest tweets one at a time in the animated rotation.
Recent Facebook Posts: Lists most recent Facebook posts from public Facebook pages. A faster, prettier, and more customizable alternative to Facebooks Like box.
oAuth Twitter Feed for Developers: Twitter API 1.1 compliant plugin that provides a function to get an array of tweets from the authorized users. Twitter feed for use in themes.
Alpine PhotoTile for Instagram: Simple, stylish, and compact plugin for displaying Instagram photos in a sidebar, post, or page.
Instapress: Highly customizable plugin to display Instagram photos in a sidebar widget, a post, or on a page. Also an image gallery with paging functionality.
WP Facebook Open Graph protocol: Adds proper Facebook Open Graph Meta tags and values to your site so when links are shared it looks awesome!
Facebook Widget: This widget adds a simple Facebook page Like widget into your WordPress website sidebar. Also enabled shortcode for post and pages.
WPBook: Plugin to embed WordPress Blog into Facebook Platform. Requires PHP 5. Requires ability to access your WordPress blog via HTTPS (SSL).