Dear friend,
As per the PF Act, if an establishment has 20 or more employees, then it is to be covered under PF.
APPLICABILITY OF EMPLOYEES' PROVIDENT FUND AND MISCELLANEOUS PROVISIONS ACT '1952
The Employees' Provident Fund and Miscellaneous Provisions Act 1952 applies to the whole of India except Jammu & Kashmir. Employees' Provident Fund and Miscellaneous Provisions Act 1952 is applicable to: Every establishment which is engaged in any one or more of the industries specified in Schedule I of the Act or any activity notified by the Central Government in the Official Gazette. (List of Industries/Establishments) Employing 20 or more persons. Cinema Theatres employing 5 or more persons.
If you are covering them under PF/ESI, then the establishment giving a contract to you will deduct PF/ESI as the principal employer. To avoid this, if you cover them, it is a good motivation for your employees also, is it not? See the website
EPFO for further information.