Background check includes 4 aspects
1. Criminal check (based on last 5 years address ): more address more time, 1~3 weeks unto city
2. Employment history (based on your 7 years pay roll history): usually 1 week
3. Reference check(based on phone call): 1~3 days
4. Drug screen: Upon completion of above 3: 3 business day.
Why did I need 2.5 month? My 1 (5 y) and (7 y) spans experiences in China. And they checked those too, cause we are financial company. They outsource those check to investigation company. No clue how.