Most businesses reconcile input credit once a year, usually under pressure, usually when it is too late to do anything about what they find.

The difference between 2A and 2B

GSTR-2A is dynamic. It updates continuously as your suppliers file. What it shows today is not what it showed last week.

GSTR-2B is static. It is generated once for each tax period and does not change afterwards. It is the statement your eligibility is assessed against.

The practical consequence: use 2B to decide what to claim, and 2A to investigate why something is missing from 2B.

Why monthly beats annual

Because of leverage.

If you reconcile in month one and find that a supplier has not filed, you probably have not paid them yet. That is a conversation with a lever in it.

If you find the same thing eleven months later, you have paid, the relationship is settled, and your only remaining option is to ask nicely.

The credit is the same in both cases. Your ability to recover it is not.

A checklist that works

Pull 2B as soon as it is generated. Do not wait for the filing deadline; the point is to have time.

Match on invoice number and value, not just total. A matching total with mismatched line items hides two errors that happen to cancel out.

Bucket the differences into three piles. Timing (supplier filed in the next period), error (wrong GSTIN, wrong value, wrong period) and absent (supplier has not filed at all).

Chase the third pile in writing, that week. Email, not a phone call, because you want a record and because the record is what makes the follow-up easy.

Track repeat offenders across months. One missed filing is an accident. The same supplier three times is a commercial decision you are making without realising it.

Sizing the exposure

The number worth knowing is not this month’s gap. It is what habitually late suppliers cost you across a year.

If ₹2 lakh a month of your purchases come from suppliers who file unreliably, at eighteen per cent that is ₹4.32 lakh of credit at risk annually. That figure usually reframes how much effort the chasing is worth.

When the gap runs the other way

Sometimes 2B shows more than your books. That is credit sitting unclaimed, which is recoverable — but only within the statutory window, which is another reason monthly beats annual.