<h1>HSN code reporting: Third phase mandate requires enhanced table 12 and table 13 reporting for GSTR 1 returns from May.</h1> From the May return period of 2025, Phase Three on the GST Portal will make enhanced HSN Code reporting in table 12 of GSTR-1/1A mandatory according to Aggregate Annual Turnover criteria, and will also mandate completion of the documents list in table 13; taxpayers must update filings per the portal advisory.