Drupal 6 sites will continue functioning after support ends in February 2016 but will be vulnerable without security updates, so sites are advised to upgrade to Drupal 7 or 8 to access new features and ongoing support. While Drupal 6 sites can pay vendors for extended support, upgrading to Drupal 8 is recommended to benefit from the latest technology. Drupal Geeks can help assess and guide upgrading Drupal websites.

1. Drupal 6 Long Term Support
Although Drupal 6 will no longer be supported, Drupal 6 sites will still be capable of
running "as-is" well after February 24, 2016. The only negative here is new found
Drupal 6 security vulnerabilities will unlikely be addressed by core developers which
will put site security at stake.
Moreover Drupal 6 was released long time back and there are lot of cool new
features are available in Drupal 7 and 8. So you should plan to upgrade your site as
soon as possible.
For sites not updated before February 24th 2016, Drupal.org has announced few
vendors who are willing to provide paid support for Drupal 6 sites beyond February
24th, 2016.
Drupal 6 Long Term Support (D6 LTS) vendors:
1. Tag1 Consulting
2. myDropWizard
3. Acquia
If you are on Drupal 6 currently, it would make tremendous business sense to
move directly to Drupal 8 that has the latest technology under its belt.
For a thorough assessment and professional guidance on upgrading your Drupal
website, Drupal Geeks can be reached out @ 312-340-7112 or send an email to
consult.drupalgeeks@ameexusa.com