The best replacement for facebook chat is messenger.

The best alternatives to facebook chat are rated as following:
★★★★★  messenger
  mobile

Your alternative for facebook chat is not listed? Suggest!
Speaking about facebook chat, one probably shouldn't forget about phone icon.

Other search terms related to facebook chat and their ratings are:
★★★★★ phone icon
★★★★★ aim
★★★★ yahoo messenger
★★★ adium
You have in mind a companion for facebook chat and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of facebook chat in all years. Click on graph for more.
facebook chat
messenger
mobile