Underwriter handbook · Canonical guide
Average Bank Balance (ABB / AMB) Calculation: 5th, 10th, 15th, 25th Installment Date Analysis
A practical ABB / AMB handbook for SME and personal-loan underwriters: installment-date sampling, kite-flying pitfalls, and how FinAnalyser reports genuine cleared balances. Open the free AMB / ABB calculator.
ABB / AMB formula (cleared EOD)
Prefer end-of-day (EOD) ledger balances after all credits and debits post — not intra-day peaks. FinAnalyser derives EOD from chronological ledger continuity at paisa precision.
Why lenders inspect 5th, 10th, 15th, 25th
- Many EMIs and NACH mandates debit between the 5th and 15th — balances on those dates reveal stress.
- Salary often credits early month; a strong 1st–3rd balance can hide a weak mid-month trough.
- 25th / EOM samples catch month-end sweep and OD/CC limit pressure before the next payroll.
- Averaging multiple installment-aligned dates resists cherry-picking a single high closing.
Observation
5th
Observation
10th
Observation
15th
Observation
25th
How circular kite-flying inflates ABB
Related-party credits that reverse within hours or days can leave a high EOD print on an observation date even though liquidity never stayed. Bounce washes (credit then CHQ DEP RET) similarly inflate gross activity and momentary balances.
- Self-transfers / inter-account rounds should not count as operational inflow.
- Provisional cheque credits that later return must not define “cleared” ABB.
- Underwriters should compare ABB with net operating cashflow after bounce/contra deductions.
How FinAnalyser extracts genuine cleared balances
- Chronological normalize (ASC/DESC) with
source_row_indexso same-day order does not scramble the running balance. - Enforce CBS continuity: Balance[n−1] + Credit[n] − Debit[n] == Balance[n] (paisa).
- Exclude own-account contra from operational cashflow; keep bounce events unmerged for underwriting.
- Emit ABB/AMB observation windows (including 5th/10th/15th/25th-style sets) inside the 28-sheet institutional Excel.
From ₹10/statement · 3 free analyses
FAQs
What is ABB / AMB in bank statement analysis?
Average Bank Balance (ABB) or Average Monthly Balance (AMB) is the mean of end-of-day balances over an observation window. Indian lenders often sample key calendar dates (e.g. 5th, 10th, 15th, 25th) instead of relying on a single closing balance.
Why do lenders care about installment dates?
EMI and mandate debits often hit mid-month. Observing balances on 5th/10th/15th/25th shows whether the account stays liquid around obligation dates — not only after a salary credit on the 1st.
How does kite-flying inflate ABB?
Circular credits between related accounts (or bounce washes) can temporarily lift EOD balances. If those contras are not excluded, ABB looks healthier than true cleared liquidity.
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