Full article on the Reebok deal with the UFC can be found here:
http://www.the42.ie/ufc-reebok-deal-reaction-2088809-May2015/Here is the basic pay breakdown:
The Reebok money will be distributed based on each fighter’s tenure with the UFC:
1-5 bouts — $2,500 per fight
6-10 bouts — $5,000 per fight
11-15 bouts — $10,000 per fight
16-20 bouts — $15,000 per fight
21 bouts or more — $20,000 per fight
Title challengers — $30,000 per title fight
Champions — $40,000 per fight
It also states that guys like McGregor, who have an individual deal with Reebok, will make much more than fighters who aren't individually sponsored.