Consultants vs. Employees
A consultant is not an employee. As such, he is not expected to follow the leave rules, rules relating to hours of work, office timing, etc. His fee will be paid as per the bill raised by him. No PF is deducted from it. He is given Form 16A and not Form 16 in respect of TDS deducted. As such, he is not an employee and not eligible for leave or leave encashment.
Consultants in IT Companies
However, many IT companies, who believe that labor laws are not applicable to them, engage employees as consultants! They are designated as consultants but are expected to reach the office on time, remain in the office for 8 to 9 hours, follow the dress codes on par with others, avail leaves, report to somebody on a daily basis, etc. This is an arrangement to avoid paying PF, bonus, and other benefits available under labor laws. When he leaves the organization after long service, he will not be paid gratuity, saying that he was not an employee.
If your consultant falls under the second type, he should be given leave encashment.