Quarterly BAS Due Dates 2026-27: The Complete Calendar

Quarterly BAS due dates 2026-27

Concession dates apply to eligible businesses lodging through a registered agent or, for some, electronically. Confirm your exact date in ATO online services or with your agent. When a due date falls on a weekend or public holiday, the next business day applies.

Monthly BAS due dates

Turnover of $20 million or more, or by choice or ATO requirement, means BAS is monthly, due the 21st of the following month, with no agent extension for GST. July's BAS is due 21 August, and so on. December's is due 21 January, though small businesses lodging electronically often get until 21 February for December, so check your account.

Payment is due the same day as lodgment

The BAS due date is a lodge and pay date. Can't pay? Lodge anyway. Lodging on time stops failure to lodge penalties even if payment waits, and the ATO sets up payment plans far more readily for businesses whose lodgments are current. An unlodged BAS also stops the ATO seeing that you're engaged, which is the fastest route from cash-flow hiccup to compliance target.

What a late BAS costs

Each late BAS attracts its own failure to lodge penalty, $364 for each 28 days late, capped at $1,820 for small entities (double for medium, five times for large), and unpaid amounts accrue GIC at 11.43% p.a., compounding daily and no longer deductible. Four quarters of unlodged BAS means four separate penalty caps, up to $7,280 before interest. Run your exposure with the penalty and interest calculator. Several BAS and tax returns behind? Order of operations matters, and the overdue returns guide covers it.

PAYG instalments and super: same dates, different rules

• PAYG instalment notices that you pay without varying don't need lodgment, just payment by the 28th. Vary the amount and it becomes a lodgment with the same due date.
• Super guarantee is due on the same 28th dates (28 October, 28 January, 28 April, 28 July) but has no agent extension ever, and late super triggers the super guarantee charge regime, which is dramatically harsher than BAS penalties. Never let the BAS concession dates lull you on super.

BAS calendar and penalty rates checked July 2026.

General information only - not personal tax, financial or legal advice. Consider your own circumstances or speak to a registered tax agent. Remission of penalties or interest and payment plans are decisions of the ATO and outcomes can't be guaranteed.