CBA October Rate Rise: Three Dates to Check

What changes on 9 October?

CBA has announced a 0.25 percentage point increase in variable home loan rates, effective 9 October 2026. Its customer notice separates the rate's effective date from the date it appears online and the date a changed principal-and-interest repayment is displayed.

Those dates answer different questions. A later app update does not mean interest keeps accruing at the old rate until the screen changes. Use the account rate, balance and remaining term in the Mortgage Repayment Calculator for an indicative scenario.

The three published dates

CBA says the repayment message includes the change's effective date. 11 October is not a universal new repayment due date. The notice also distinguishes published reference rates from rates after individual discounts.

Sources: CBA customer rate notice and September rate decision announcement, checked 8 October 2026.

A rate example, not a CBA quote

Suppose a hypothetical variable account rate is 6.10% before a 0.25 percentage point increase. The new rate is 6.35%, calculated as 6.10% + 0.25 percentage points.

Multiplying 6.10% by 1.0025 would answer a different question. It would not reproduce a quarter-percentage-point increase. Equally, multiplying an existing repayment by 1.0025 does not calculate the new scheduled repayment: that calculation also needs the balance and remaining term.

For a split loan, do not apply a variable-rate change to every dollar automatically. Record the affected variable portion separately from any fixed portion. The split home loan worksheet shows how a change to one portion flows through an illustrative combined rate and repayment.

Keep a small record for each account

Before comparing an estimate with a lender message, record:

• The account or split identifier, so two notices are not confused.
• The old and new account rates, with the effective date beside them.
• The outstanding balance and remaining repayment term.
• The new required repayment and its own start date from the account notice.
• The payment method and frequency, including any separate standing transfer.

This is a practical checking worksheet, not a direction to change a payment arrangement. If two dates or amounts conflict, the bank needs to explain the account-specific treatment. The rate-change checklist provides a fuller list of questions.

What changes in our calculators?

No formula change follows from this lender announcement. Calculator examples and default inputs are not personalised CBA rates. Enter the relevant account rate instead of copying an advertised reference rate or the RBA cash rate.

A constant-rate repayment estimate also does not reconstruct a statement period containing two rates. See how daily home loan interest works and the statement balance worksheet for those separate checks.

Who may be affected, and what remains uncertain?

This update concerns the CBA variable home loan notice. It does not establish the terms of a fixed-rate account, another lender's product, or a particular customer's repayment instruction. The separate ANZ October notice summary should not be used to infer CBA account settings.

Individual discounts, balances, payment schedules and later notices can change the dollar result. This article makes no forecast of the next cash-rate decision and does not compare or recommend bank products.

Sources and limitations

• CBA: Home loan rates announcement, checked 8 October 2026. This is a changing customer-notice page; recheck it before relying on the timetable.
• CBA: September 2026 interest rate decision, checked 8 October 2026.
• The 6.10% example is invented arithmetic, not an advertised or customer rate.

General information only, not financial, credit, legal or tax advice, a loan quote, approval or product recommendation. Confirm account details with the lender and speak with a licensed professional where appropriate.

Last updated: 8 October 2026.