As per Census of India 2011, the Mumbai urban agglomeration forms a major urban magnet for migrant construction workers. The construction sector comprises principally informal workers whose conditions of work are mainly regulated by three laws, viz. the Interstate Migrant Workmen Act, 1979, the Building and Other Construction Workers (Regulation of Employment and Conditions of Service) Act, 1996, and the Contract Labour (Regulation and Abolition) Act, 1970. Analysis suggests that these laws do not take into account the nature of informality in the sector. In addition to this, the amalgamation of these labour laws, with several others, into four labour codes further adds to the vulnerabilities of interstate migrant workers by not considering how vulnerabilities of migrant workers vary according to their sector and place of work. This paper explores the status of employers with respect to growing informalisation of workforce in the construction industry by taking a case study approach of an organised construction site at Thane, Maharashtra. Ninety-three per cent of the workers at the construction site were migrants, mostly from Uttar Pradesh and Bihar. Seventy-two per cent of the workers at the construction site responded that they got their wages from contractors, and in close to fifty-eight per cent of the cases, the contractor was the figure which helped them find work in the site. To understand the role of contractors better, the authors also conducted semi-structured interviews with fifteen contractors and three labour in-charges from the Thane construction site, during April and May 2020. Through these interviews, the authors found that the management sidestepped their responsibility of the workers by specifying that the contractor is the employer of the workers, while the contractors argued that they are the “recruiters” and not the employers. The paper thus tries to understand the term “employer” by comparing the definition of the employers in the three labour laws with our findings from surveys. Are there any potential areas of conflicts between the definitions? How does it get translated in the lives of workers, especially migrant workers? Do informal networks among migrant workers contribute in formulating the perception of the contractor as an employer? We do this by building up on fieldwork evidence of informality on large organised construction sites.