Dear Colleague,
There is a main code for each establishment for remittance and compliance of PF by the Employer. The employer can get sub-codes under establishment code if located in different state for easy compliance and EPFO is allotting such sub-codes also.
In the case of Sub-Code for compliance in case of Contractors can also be obtained but it is highly to be discouraged for the reason that you will end up in managing entire activities like remittance, inspections, accounting, settlements, transfers and so on including 7A Enquiries and etc. This will add your burden too much. It is always to ensure that Contractors do their own compliance and you put them into your audit radar. Leally create then as separate establishment with Contract License, PF Code, ESI Code etc as it will be a separate entity and will protect the interest of Organization in the long run in many ways. In several of my previous organizations we faced lots of challenges due to compliance under sub-code on behalf of contractors and notices received even after few years of the leaving of contractors. Approach this as " Let then do their job" manner and improve your audits on them. This is my suggestion from practical point of view and you may kindly take a suitable call after weighing pros and cons.