Mortgage Check

Was your offset account actually reducing your interest? Check the arithmetic yourself — free, private, in your browser.

Nothing you load leaves your device Nothing is stored — close the tab and it's gone No accounts, no tracking, free forever

Why this exists

In July 2026 ASIC reported that banks had paid over $55 million in compensation for offset accounts that were opened but never linked to the home loan. Nothing on a statement says "offset not applied" — the only way to see it is to redo the interest arithmetic, which is what this page does.

How the check works

Australian variable home loans accrue interest daily on the closing balance and charge it monthly. For each monthly charge on your statement, this tool rebuilds the daily balances and computes what the interest should have been in two worlds — offset linked, and offset ignored — then checks which one your bank's actual charge matches.

Run the check

Load your statements as PDF or CSV — whichever your bank gives you. Several files at once is fine; they're stitched together in date order.

How much do I need to load?

Ideally, back to when your offset account was opened or linked — that is where unlinked offsets usually start, and it is the period a bank would remediate.

The practical minimum is about 12 months. Australian lenders issue home loan statements every six months — that is the maximum period the law allows for a term loan, and most sit on it — so a year is typically two PDF statements. Anything less rarely shows a pattern.

What matters most is that there are no gaps. The check rebuilds your daily balances, so a missing month makes every period after it unreliable. Overlapping files are fine — duplicates are removed automatically. Once you load something, the panel below tells you whether your coverage is enough.

Step 1 · Loan account

Your home loan statements or transaction export.

no statement loaded — or drag & drop here

Step 2 · Offset account (optional)

Your offset account statements over the same period.

no statement loaded — implied mode will be used
Statement won't load? Paste the text instead

Open the statement, select the transaction list, copy it, and paste it here. One transaction per line — date, description, amount, then the running balance.

Step 3 · Interest rate — worked out for you

Nothing to do here. Your interest rate is calculated from the statements themselves, and the check tells you which rate it used so you can confirm it.

Set the rate manually

Only needed if the rate can't be worked out, or you want to override it. Anything entered here takes precedence.

Effective dateRate % p.a.

Advanced options
Where to find your statements

Two routes, and it's worth knowing which one your bank gives you.

In the mobile app — PDF statements

Nearly every Australian banking app can download statements as PDF, usually under Statements, Documents, or Statements & documents — either inside the account or under your profile menu. Most banks keep seven years of statements there. This is the route to use on a phone; almost no banking app can export transaction data as CSV.

In desktop internet banking — CSV export

Open the account's transaction list and look for Export or Download, usually above or beside the list. Choose CSV. Formats vary — CSV, OFX, QIF, and sometimes others — and any of the plain-text ones will work here if you pick CSV.

Password-protected statements

Statements that arrive by email are usually locked with a password — often your date of birth in a format the covering email describes. Load them here as they are. The page will ask for the password and unlock the file itself; there is no need to open it in a PDF editor and re-save it. The password is used in this tab only, and is neither stored nor sent anywhere.

Statements downloaded from internet banking are normally not locked, so if you have the choice, downloading is the smoother route — and it is also where the longer history lives.

Things that quietly cost people data

  • Export windows are far shorter than statement archives. Transaction export usually reaches back one to two years; PDF statements typically go back seven. For older periods the PDF route is often the only one.
  • Some banks only export what is on screen. At least one lender requires you to page through the whole transaction list first — otherwise the file is silently truncated, with no warning. If an export looks short, check it against the dates you asked for.
  • An app can hold less than the website. At least one major bank shows two years of statements in its app but seven in desktop internet banking. If the statement you need isn't in the app, look on a computer before concluding it's gone.
  • Some offset and joint home loans still get posted paper statements. At one major banking group, home loans qualify for online statements only when solely owned — a loan that is joint, or that has an offset arrangement, is posted instead. If yours isn't online, that may be why, and the statutory request below is the way through.

How often statements are issued

Australian home loan statements are usually issued every six months, and there's a legal reason: the National Credit Code sets six months as the maximum statement period for a term loan, and most lenders sit exactly on that ceiling. So a year of loan history is typically two PDFs, and five years is ten. A few lenders issue monthly. Offset and everyday accounts are statemented more often — monthly to six-monthly — and many banks will switch you to monthly on request.

Two useful consequences of the same law: your loan statement must show the interest charged and the interest rate, which is exactly what this tool needs. But it is not required to print a running balance against each line — so if yours doesn't, that's normal, and the tool rebuilds the balances from the opening balance instead.

One exception worth knowing: if your rate is fixed for the entire term with no provision to vary it, your lender may not be required to send statements at all.

If your bank gives you nothing usable

You have a statutory right to the data. Under the National Credit Code you can ask your lender in writing for the current balance and every amount credited or debited over a period you nominate. They must respond within 14 days for a period within the last year, or 30 days for anything older. Banks subscribing to the Banking Code of Practice separately undertake to provide copies of documents, including statements of account, within 30 days — they may charge a reasonable fee for that.

That is the route when a lender has no export at all, when its online history doesn't reach far enough back, or when your statements only ever came on paper. Ask for it as a written request, and keep the date you sent it.

Before you contact your bank

This tool models the standard contract: daily accrual on the closing balance, actual/365. It does not know your specific product terms, and each of these can produce a false positive:

  • Some fixed-rate loans only offset partially, or not at all — check your loan contract.
  • Interest may be calculated to the day before the charge date or include the charge date, shifting a period by one day's interest.
  • Fees bundled into an "interest and fees" line will not reconcile.
  • A rate change mid-period that isn't in your rate table will show as PARTIAL / UNCLEAR — fix the rates and re-run before drawing conclusions.

Treat the output as a prompt to ask your bank a specific question — "why does the December interest charge match an unoffset balance?" — with the daily arithmetic to back it up, not as a finished conclusion.

If a problem is confirmed, banks are required to remediate this kind of set-up error. If their internal complaints process doesn't resolve it, you can escalate to the Australian Financial Complaints Authority free of charge.

How your data stays yours

This page is a single file with no server behind it. Your statements are read in your browser's memory, the arithmetic runs there, and nothing is uploaded, cached or written anywhere — there is no code on this page capable of sending data out, and its security policy (connect-src 'none') forbids network calls outright. You can verify that yourself: open your browser's developer tools, watch the Network tab while you run a check, and view this page's source.

That includes PDFs. Statements are not sent to any conversion service — the PDF reader is part of this page, written out in full in the source, so a statement you load never leaves the tab it was opened in. Password-protected statements are unlocked here too; the password is used to read the file and is never stored or transmitted.

The page also loads nothing from anywhere else — no analytics, no trackers, and even the typefaces are served from this site rather than a font service, so opening it doesn't announce your visit to a third party.

Never share your banking password with any tool, including this one — it only ever needs the statement files you download yourself.