Advanced reconciliation rules help you clear invoices that basic reconciliation could not match, without checking them one by one. You choose the rules before you submit a reconciliation request, as described in the article “IMS: Perform Reconciliation”. There are two groups of rules: rules for missing invoices, and rules for mismatched invoices.

Analyse Missing Invoices (advanced rules)

These rules look for matches among the invoices that are left in Purchaser Only and IMS Only after basic reconciliation. When a rule finds a match, the pair moves to Match, Value Mismatch or Invoice Mismatch. Start with the first three rules. Use the amount-based rules (3 and 4) only when the invoice numbers cannot be matched at all, and review their results carefully.

Rule	Use it when
1. Across Financial Year	The invoice sits in a different financial year in your register than in IMS. The invoice date decides which financial year an invoice belongs to. You can combine this rule with any other rule.
2. Fuzzy Logic on Invoice Numbers	The invoice numbers differ by special characters, leading zeros, prefixes or suffixes, for example 100 in your register and MUM100/17-18 in IMS. The invoice dates must fall in the same month.
2.1 Invoice Series Matching	The invoice numbers differ in how the series is written, for example A1001/24-25 in your register and A1001/2024-2025 in IMS. The system compares the serial number inside each invoice number (1001 in this example) for the same supplier and the same month. If several purchase invoices share that serial number, it picks the closest one within the tolerance you enter on the total tax amount (0 is allowed). The rule is skipped when an invoice number contains more than one serial number.
3. Ignore Invoice No., exact amounts	The invoice numbers cannot be matched, but the invoice value, taxable value and tax amounts are identical in the same month. Sub-options 3.1 and 3.2 also ignore the invoice value, and then the taxable value, so that only the remaining amounts are compared.
4. Ignore Invoice No., within tolerance	The same as Rule 3, but the amounts only need to be within a tolerance that you set, plus or minus. The tolerance is required. Sub-options 4.1 and 4.2 ignore the invoice value, and then the taxable value.
5. Amended Supplier Only vs Original Purchaser	The supplier amended an invoice (B2BA, CDNA) that you booked as the original. The supplier’s original invoice moves to Original SO Amended.
Ignore Month	The same invoice carries different document months in your register and in IMS. Run it together with other rules.

Ticking a sub-option automatically ticks the rules it depends on. If one purchase invoice has several possible matches, it is marked Probable Match, and you pick the right one from a drop-down list. You can limit any run to up to 25 Counterparty GSTINs. Enter them as a list without commas.

Analyse Mismatched Invoices: move near-matches to Deemed Match

These rules move invoices from Value Mismatch or Invoice Mismatch into Deemed Match when the difference is within a tolerance that you set. The screen warns you to check the mismatches first, because moved invoices are treated as matches from then on.

1. Value Mismatch within tolerance. Enter a MIN (a negative number or 0) and a MAX (a positive number or 0). The tolerance is your value minus the supplier’s value, and MIN and MAX cannot both be 0. For example, with MIN -10 and MAX 10, an invoice whose value in your register is up to 10 lower or 10 higher than in IMS moves to Deemed Match. Then tick at least one of Invoice Value, Taxable Value or Tax Value (with or without Cess) to say where the tolerance applies. If you tick none, nothing is moved and no error is shown. If you tick several, all of them must be within the tolerance.
2. Invoice Mismatch within tolerance for Invoice Value. The same MIN and MAX fields apply, and the tolerance is checked on the invoice value.

You can also choose fields whose mismatch should be ignored, for example Place of Supply, Invoice Type, Reverse Charge and Invoice Date. A positive tolerance means that your value is higher than the supplier’s, so you claimed more ITC than the supplier reported.