Mortgage Statement Worksheet: Why Did the Balance Change?

Short answer

To explain a mortgage balance movement, start with the amount owed at the beginning of the statement period, add transactions that increase the debt, then subtract credits that reduce it. Compare that result with the closing balance for the same account and period.

Opening amount owed + interest and other debits - repayments and other credits = closing amount owed.

This worksheet treats money owed as a positive number. Some statements show debt with a minus sign or a debit label, so translate the labels before doing the arithmetic. It is a check of posted transactions, not an independent recalculation of the interest charge.

Use the Mortgage Repayment Calculator for a future repayment scenario. Use the statement itself for what actually posted.

A worked statement reconciliation

The figures below are invented, not a typical loan, recommended payment or lender statement. Assume every listed item posted within one statement period and there were no other transactions.

The closing debt is $490 lower, even though the borrower paid $4,000. Interest, the fee and the redraw together increased the amount owed by $3,510. Subtracting that from $4,000 explains the $490 reduction.

Without the redraw, and holding every other posted amount unchanged solely for this accounting comparison, the closing balance would be $498,510. That is not a fresh interest simulation: removing a real redraw could also change daily interest.

Do not subtract the $4,000 again from the closing balance. The payment credits are already included.

Build your own five-column worksheet

Copy these headings into a private spreadsheet or onto paper:

Use the exact statement period. A calendar month, a downloaded transaction report and a six-month statement can cover different dates. Reconcile each loan split separately before adding balances together.

HomeStart's statement guide explains opening balances, debits, credits and transaction dates. Product-specific labels and features differ, so use the guide for the lender that issued the statement when a field is unclear.

Keep an offset balance outside the debt reconciliation

Suppose the example loan closes at $499,510 and a separate offset account holds $20,000. The worksheet still shows $499,510 owed on the loan. The offset money has not been credited as a loan repayment merely because it is linked.

CommBank's statement guide distinguishes the loan balance from the balance used to charge interest when an eligible offset applies. Check the product's actual offset terms. For scenario modelling, see the Extra Repayments Calculator and offset account verification checklist.

If a payment moves from the offset into the loan, record the credit on the loan once. A consolidated view can also show the reduction in the separate cash account, but it must not count that movement as a second loan repayment.

When the numbers do not match

First check whether the opening balance belongs to the preceding period's closing date. Then check missing pages, reversed payments, refunds, fees, redraws and transactions that posted outside the selected dates. A scheduled payment is not necessarily a posted credit.

Matching the arithmetic only confirms that the listed transactions explain the closing balance. It does not confirm that a fee was authorised, the interest was calculated correctly or all repayments were on time. Ask the lender to explain an unfamiliar entry or unresolved difference.

To inspect interest separately, keep the daily balances, applicable rates, rate-change dates and offset information. The daily home loan interest explainer addresses that different task. The rate-change checklist helps identify which dates to record.

A closing balance is not a payout quote

CommBank explicitly notes that its statement loan balance is not a payout figure. For a refinance or sale, obtain the lender's figure for the intended discharge date. Do not insert a historic statement balance into a settlement budget and label it a confirmed final debt.

Sources and limitations

• HomeStart: Understanding your loan statement, checked 6 October 2026, supports the meaning of transaction and summary fields; this worksheet does not apply its product-specific repayment arrangements to other loans.
• CommBank: Guide to home loan statements, checked 6 October 2026, supports the loan balance, offset and payout distinctions.
• The worksheet, transaction amounts and reconciliation are original hypothetical examples.

General information only, not financial, credit, legal or tax advice, a lender assessment, statement verification service or payout quote. Confirm unfamiliar transactions, product terms and discharge amounts with the lender.

Last updated: 6 October 2026.