Overdue BAS Help

How overdue BAS catch‑up usually works

A good overdue BAS process starts with triage, moves through clean‑up and preparation, and ends with a clear maintenance routine so you don’t fall behind again.

1. ATO and software triage — confirm outstanding BAS/IAS, check the ATO Integrated Client Account, review software access (Xero/MYOB/QuickBooks), and identify immediate risks (e.g. missing bank feeds, unreconciled payroll or unpaid super).
2. Fix the bookkeeping — bring bank reconciliations up to date, correct GST coding, capture missing tax invoices, check PAYG withholding and STP totals, and review large or unusual transactions.
3. Prepare each BAS/IAS — compile BAS figures by period, reconcile to the general ledger, GST summaries and payroll reports (W1/W2), and run a pre‑lodgement review.
4. Lodge and communicate — submit via the ATO portals (or Online services for business if self‑lodging), note due dates and amounts, and request a payment plan where needed.
5. Reduce penalties and interest — where appropriate, request remission with a clear explanation and evidence of rectification. Voluntary and timely disclosure helps.
6. Stabilise the routine — set a monthly/quarterly workflow, responsibilities, checklists and reminders. Consider a BAS Review or BAS Setup to lock in the process.

Australian context to keep in view

• BAS reports GST, PAYG withholding (W1/W2) and/or PAYG instalments. Some businesses also lodge IAS monthly for PAYG only.
• Registered BAS/tax agents use ATO Online services for agents and can request payment plans and, in many cases, penalty or interest remissions.
• Lodge even if you cannot pay immediately. The ATO generally prefers on‑time lodgement with a payment plan over silence.

Related topics: BAS Catch Up Services, BAS Corrections, and the broader BAS Agent Services hub.

Common overdue BAS scenarios we fix

• 2–4 quarters late after a software change or bookkeeper turnover.
• Monthly reporter fell behind on IAS due to payroll or cash flow pressure.
• GST coding errors discovered in a year‑end review that require BAS amendments.
• ATO reminder or default assessment letters received; need a plan to respond.
• New business mis‑set GST in software; first BAS needs correction and education.

What to compare before you commit

What happens when BAS is overdue?

• Penalties — the ATO can apply a Failure To Lodge penalty that increases for each 28 days late, up to a cap that varies by business size.
• Interest — General Interest Charge may apply to unpaid amounts until paid in full or covered by a plan.
• Refunds — BAS refunds may be withheld if other obligations are overdue.
• Compliance action — repeated non‑lodgement can trigger firmer ATO follow‑up. Proactive contact helps.

Good news: lodging quickly and providing a reasonable explanation often improves the outcome. If the ATO issued a default assessment, you can usually replace it with correct figures by lodging the actual BAS.

Pricing and timelines

Every backlog is different, but these ranges can help you plan:

• 1–2 overdue BAS — typically 2–10 business days once records are provided; pricing depends on bookkeeping quality and payroll complexity.
• 3–6+ periods — usually 2–6 weeks with staged lodgements and ATO updates along the way.
• Amendments — if prior BAS need corrections, expect extra review time to reconcile GST and payroll totals.

Ask for a written scope with deliverables, a staged timeline, and whether ATO requests (payment plans/remissions) are included.

Best next steps

1. List which BAS/IAS periods are overdue and gather ATO letters.
2. Export your GST and payroll reports for those periods from your software.
3. Decide whether you want a once‑off catch‑up or ongoing BAS support.
4. Shortlist providers using the scope and fit criteria above.

Ready to move? Use the form below for tailored help, or read these related pages first: BAS Catch Up Services, BAS Lodgement, and BAS Corrections.