When a supplier's invoice sits in GSTR-2B but your books show it under a different number, a different date or a slightly different amount, the reconciliation leaves both sides "one-sided". In Smart Books you can map a GSTR-2B invoice to its purchase bill by hand, so the two rows are treated as one bill. Here is how mapping works, when to use "Partial match" versus "Fully matched", and what happens if the supplier amends the invoice later.
Why a bill goes unmatched in the first place
The automatic matching looks at the supplier, the amounts, the invoice number and the date. Most bills pair up without help. The ones that do not are usually ordinary data-entry differences: the invoice number was never entered in the purchase voucher, the supplier dropped a series prefix, or the bill was booked in two parts. Those rows land under "In portal, not in books" and "In books, not in portal" on the reconciliation screen.
If you already follow a monthly routine for matching GSTR-2B with your purchase register, this is the step for the stubborn leftovers.
Where to find it
In Smart Books, open GST and then Reconciliation. Choose GSTR-2B Reconciliation (there is a GSTR-2A one too, which works the same way). Select the period and sync. The one-sided rows appear on their own tabs, and each row offers the action "Map to a voucher and set its status…".
How to map a GSTR-2B invoice, step by step
- Start from either side. Pick a portal invoice that is not in your books, or a voucher that is not on the portal. The dialog is titled "Map this invoice and set its status" and shows the row you started from.
- Choose the other half. The candidates are ranked for you. Each carries small flags such as "Different supplier GSTIN", "No invoice number entered", "Taxable differs by …" or "2 days apart". You can search by invoice number, bill reference or supplier. Nothing is pre-ticked, because you are the one asserting that these are the same bill.
- Tick the voucher(s). From a portal row you can tick several vouchers, for example when one supplier bill was booked in parts. From a voucher you can pick only one portal invoice, since one voucher cannot be several invoices.
- Read the footer. It tells you how many rows you selected and either "the money agrees" or by how much taxable value and tax differ. A gap of up to ₹1 on each is treated as agreeing.
- Pick the status (explained below), optionally add a reason and a note, then press the save button.
Mapping records that the rows are one bill. Neither document is changed, and the difference between them stays visible on the row.
Partial match or fully matched?
This is the choice that matters. The dialog describes them in one line each:
StatusMeaning in the dialogUse it when Partial matchSame bill, a correction still owedYou know it is the same bill, but a figure or detail still needs fixing in your books or with the supplier. Fully matchedNothing left to do on this billThe only difference was the invoice number or date format, and the money agrees.Partial match is the default. If you choose "Fully matched" while the taxable value or tax still differs, Smart Books warns you: the period would report the credit as agreed on figures that do not agree, and the difference will not be chased. Treat that warning seriously, because input tax credit rests on these figures.
Record why you mapped it
The reason is optional, and the screen never forces you to justify a mapping. It is still worth choosing one, because a reason can be counted later. The list includes:
- Invoice number not entered in books
- Invoice number keyed differently
- Data entry error in books
- Supplier filed wrong details
- Supplier filed under another GSTIN
- Supplier amended the invoice
- Rounding or discount difference
- Timing difference between books and portal
- Duplicate entry in books
- Invoice booked in parts
- Other (see note)
If most of your mappings say "Invoice number not entered in books", the fix is at the data-entry desk, not in next month's reconciliation. A short note of up to 500 characters helps whoever reads the period next, whether that is a colleague or your CA.
Let Smart Books suggest the pairs
When a period has many unpaired rows, a strip under the report shows how many likely pairs were found among the portal-only and books-only rows. Press Review and map to open "Suggested mappings". Each pair is computed from the supplier, the money, the invoice number and the date, so the same two sides always give the same suggestion. Nothing is mapped until you confirm.
You can filter by supplier, confidence, status or reason, search by invoice number, and tick "Money already agrees". The footer lets you map the selected pairs in one batch, using each row's own suggestion or one status and reason for all of them. After a batch, an Undo button reverses it. The "Review this batch" button asks the assistant to summarise what the batch is made of, for example one supplier dropping its series prefix. It only summarises; it never maps anything.
What happens when you re-sync or the supplier amends
Mappings are not lost when you sync again. Smart Books recomputes the reconciliation and applies your mappings on top. Before a re-sync, it tells you how many hand-made mappings the period has.
There is one exception worth knowing. If the portal invoice changed after you mapped it, for instance because the supplier amended it, your chosen status is not applied. The pair is reported as "Mapping needs review — portal invoice changed" until you confirm it against the new figures. In the GST Reconciliation Centre, the period then shows a "Mappings to review" card, so a month is not closed on credit that nobody re-checked. The Centre is read-only; you act on those pairs from the GSTR-2B Reconciliation screen.
Key takeaways
- Map by hand only the bills the automatic matching could not pair: wrong number, split booking, odd formatting.
- Use "Partial match" when something is still owed, and "Fully matched" only when the money agrees.
- Pick a reason, so repeated causes show up and can be fixed at source.
- Re-syncing keeps your mappings, but an amended supplier invoice sends the pair back for review.
- Clear the "Mappings to review" items before you rely on the period's ITC figures. Before filing, run through our GSTR-3B pre-filing checklist, and confirm doubtful ITC cases with your CA.
Once your purchases are reconciled, the same discipline carries over to the GSTR-1 versus GSTR-3B check and to bank reconciliation. If you use Smart Books, the manual map dialog is the quickest way to settle the leftovers each month, with a record of who decided what and why.
