Yes, and in fact a joint RERA complaint is often the more strategic route when multiple flat buyers in Mumbai are facing the same grievance against a single builder — whether it's delayed possession, non-delivery of promised amenities, or structural issues across a project. The Real Estate (Regulation and Development) Act, 2016 does not restrict complaints to individual buyers acting alone; MahaRERA regularly entertains joint or collective complaints where several allottees of the same project have a common cause of action against the promoter. This approach saves time, reduces litigation costs per buyer, and often carries more persuasive weight before the Authority since it demonstrates a pattern rather than an isolated dispute.

Procedurally, a joint complaint is filed under the same complaint format prescribed by MahaRERA rules, with each buyer listed as a co-complainant and their individual agreements, payment details, and grievances annexed separately even though the relief sought may be common. It is advisable that the buyers be represented through a common set of facts but retain their individual financial claims clearly itemised, since the Authority will pass orders addressing each allottee's specific dues, refund amount, or compensation even within a joint proceeding. Many flat purchasers' associations across Mumbai's suburbs have successfully used this route against builders in stalled or delayed projects.

There is also the option of filing through a registered association of allottees, which RERA recognises under Section 19 read with the relevant rules, giving buyer collectives a more formal standing to pursue builders on structural defects, common area disputes, or project abandonment. This is particularly effective in large Mumbai projects where dozens or hundreds of buyers are affected, as it prevents the builder from settling with a few vocal complainants while ignoring the rest. Courts and MahaRERA generally view organised buyer action favourably, as it reflects transparency and reduces the scope for selective settlements.

That said, coordinating a joint complaint requires careful legal drafting to ensure no buyer's individual claim gets diluted or overlooked in the collective filing, which is where professional guidance becomes essential. The team at Aapka Legal Advice has coordinated joint MahaRERA filings for buyer groups across multiple Mumbai Metropolitan Region projects, ensuring each buyer's claim is properly documented and pursued. For projects requiring collective legal strategy, the Top Property Lawyers in Mumbai team can help organise buyers, draft the joint complaint, and represent the group before MahaRERA.

A panel of retired judges is available with the firm for mediation and strategic case assessment in large multi-buyer disputes, working alongside criminal lawyers where builder fraud affecting multiple buyers is suspected. If you and your fellow flat owners in Mumbai are facing a common issue with your builder, filing a joint RERA complaint is not just permitted — it is often the smarter, more powerful legal route, and organising early strengthens everyone's position considerably.