Outward supply gets less attention than ITC, but an invoice missing from GSTR-1 is the supplier-side version of the same problem — except here you are the supplier, and it is your customer whose credit fails. The gap usually surfaces months later, when a customer asks why an invoice is not in their 2B.
The sales cross-check compares the sales register against the GSTR-1 as filed for the period, and reports invoices present in one and not the other, along with those where a value differs.
The same register can be converted directly into a GSTR-1 JSON for upload, so the figures that were checked are the figures that get filed.
Run it on your own data
Purchase and sales registers exported from Tally, Busy, Marg, EasySol are read directly; anything else can be mapped column by column.
Cross-check sales vs GSTR-1 →Common questions
Which period does the comparison use?
The return period, not the invoice date. A supplier who bills on 31 March and declares it in the April GSTR-1, against a buyer who books it on 1 April when the goods arrive, is an ordinary month-end and still has to reconcile — re-basing on invoice dates breaks exactly that case.
Can it produce the GSTR-1 JSON as well?
Yes — a sales register can be converted to a GSTR-1 JSON for upload to the portal.