| Date | Obligation | |
| 11 Nov 2026 | Lodge and pay September quarterly BAS if eligible for extended lodgment concession | |
| 23 Nov 2026* | Lodge and pay October monthly BAS | |
| 1 Dec 2026 | Medium to large companies – pay 2025-26 income tax Companies required to lodge by 31 October 2026 – pay 2025-26 income tax Non-full self assessment companies – lodge 2025-26 return | |
| 21 Dec 2026 | Lodge and pay November monthly BAS | |
| 15 Jan 2027 | Lodge 2025-26 return if a medium to large company or trust not required to lodge earlier | |
| 21 Jan 2027 | Lodge and pay December monthly BAS | |
| 22 Feb 2027* | Lodge and pay January monthly BAS | |
| 1 Mar 2027* | Lodge and pay December quarterly BAS Pay second quarterly PAYG instalment for 2026-27 Lodge and pay annual GST return (if no income tax return lodgment obligation) Lodge and pay SMSF 2025-26 return (unless otherwise advised) – concession not available to a fund with overdue returns for earlier years (excluding deferrals) or a newly registered fund |
