IMS Reconciliation works best as a monthly routine. The steps below show the order in which to do things, together with the menu path for each step. Repeat them each month, before GSTR-2B is generated.

1. Upload your purchase register (2P). Go to Reconciliation > 2P/2A/2B Register > Upload Purchase Register (2P). After the upload, check for errors in the View tab and confirm your totals in 2P Summary. Reconciliation can only match the invoices that are in your register, so this step comes first.
2. Get your IMS data. Go to Reconciliation > IMS Based Purchase Recon > GET & Action IMS. This opens the IMS DATA FETCH screen, where you request your IMS data from the GST portal.
3. Perform reconciliation. Go to Reconciliation > IMS Based Purchase Recon > IMS Perform Reconciliation. Run basic reconciliation first. Then use the advanced rules to clear invoices that are in Purchaser Only or IMS Only, and finally the mismatch rules if you need them.
4. Review the results. Go to Reconciliation > IMS Based Purchase Recon > IMS Recon Result. Work through Summary Actioning, Invoice Actioning and ITC Reduction Actioning.
5. Take action and resolve differences. Accept, Reject or hold invoices Pending. Link invoices that the system could not match with Force Link or Multi Linkage, undo a wrong link with Delink, and email vendors about invoices that need their attention.
6. Save to GSTN and regenerate GSTR-2B. Use the Save to GSTN tab, check the Logs tab for errors, and then select Generate and Get 2B so that your GSTR-2B includes your decisions.

After step 6, your GSTR-2B reflects the actions you saved, and you can continue with GSTR 2B reconciliation.