Bank Reconciliation Statement Calculator and CSV Matcher

How the calculation works

1. Both files use the layout date, reference, description, debit, credit. Bank credits and cash-book debits are both treated as increases.
2. A line matches when its reference and signed amount appear exactly once on each side. Repeated references are flagged for manual review, not matched.
3. Adjusted bank balance = bank balance + items only in the books. Adjusted book balance = book balance + items only on the bank statement. The difference should be zero.

Understanding the calculation

What a proper bank reconciliation establishes

A bank reconciliation explains why the cash-book bank account differs from the bank statement on a specific cut-off date. It is not enough for the two closing figures to appear close: every reconciling item needs an identifiable bank statement reference, a payment or collection record, and a dated owner. An uncleared cheque belongs in a different category from a fee omitted in the ledger. The former is usually timing; the latter ordinarily requires a book entry.

Reading debit and credit columns

Bank statements often treat deposits as credits and payments as debits. In a company cash-book, the bank asset usually increases through debits and decreases through credits. This workbench converts both sources to the same sign convention. It then matches identical, uniquely occurring references and signed amounts. When the reference repeats, the model refuses to choose a match silently and shows it for manual investigation.

Monthly close illustration

Suppose the ledger reflects a customer deposit of ₹2,500 not yet visible at the bank. The bank has separately charged ₹500 which the ledger has not booked. Starting from the appropriate closing balances, the adjusted bank side adds the outstanding deposit, while the adjusted ledger side subtracts the fee. The two adjusted figures must meet; an unexplained residual is an exception, not a balancing plug.

Practical hand-off

Import a clean bank CSV and cash-book CSV, confirm opening/closing period and cash-book sign convention, and review unmatched rows. Download the exception file and retain the underlying statement, ledger and posting evidence. Investigate stale cheques, duplicated transaction IDs, reversals, bank corrections, interest, GST on bank charges, and cut-off items separately.

False matches and the importance of a unique key

A reference is not necessarily unique when a customer pays multiple invoices in the same transfer or a bank repeats an abbreviated narration. For large customer collections, reconcile a virtual account number or UTR along with the amount and settlement date. For supplier payments, compare bank debit evidence with cheque numbers, NEFT advice and voucher identifiers. Importing an already-cleared reconciliation file twice can introduce duplicate records; preserve the original immutable extracts and log each manual clearing decision.

How to resolve an outstanding difference

Work from balances as of a single close date. First inspect bank-only debits for fees, direct debit orders and reversed credits; then check book-only items for cheques not yet presented and deposits in transit. If the unexplained residual remains, trace all sign conventions, opening differences and currency conversions. Never create a balancing journal merely because adjusted totals disagree. The difference is a control signal requiring evidence and reviewer sign-off.

Assumptions and what this calculator does not cover

• Maximum 5,000 lines per side; each row needs a reference and either a debit or a credit.
• Unmatched items can be timing differences, omissions or errors; the tool does not decide which.
• Everything runs in your browser; nothing is uploaded.
• Bank credits are increases; cash-book debits are increases.
• Repeated or partial references remain unmatched, never auto-posted.
• A zero unexplained difference is necessary but not sufficient proof.

Official sources and further reading

• ICAI: Accounting Standards (Ind AS and AS)
• ICAI: Accounting Standards resources

Rates and rules were checked against these sources on 11 October 2026. Notifications and standards change; confirm on the official site before you file, book or advise.