What to do right now if your BAS is late
Late BAS is common after growth spurts, staff changes, cash‑flow pressure or a software switch. The fastest way to stabilise things is:
- Check your ATO Integrated Client Account to confirm how many BAS/IAS are overdue.
- Secure access to your accounting file and bank feeds (Xero/MYOB/QBO).
- Reconcile bank, sales and purchases for the overdue periods.
- Review GST codes, PAYG withholding and adjustments; fix errors before lodging.
- Prepare and lodge outstanding BAS in order, then move to a simple monthly/quarterly rhythm.
If you have ATO letters or a payment demand, you can usually request a payment plan after lodgement. A registered BAS agent can also seek remission of some FTL penalties where circumstances support it.
How a late BAS catch‑up usually works
A practical late BAS process moves in clear steps so you know what is happening and when.
- Scoping call and ATO check: confirm overdue periods, GST registration dates, and any ATO holds or payment plans.
- File health review: look for missing bank feeds, duplicate accounts, uncoded transactions and payroll/STP gaps.
- Reconciliation: bank, sales, purchases and payroll clearing accounts aligned to source documents.
- Corrections: fix GST coding, PAYG W errors, prior period adjustments and common issues like split payments or mixed‑supply GST.
- Preparation and review: draft BAS/IAS, variance checks against prior periods and reasonableness tests.
- Lodgement and ATO next steps: lodge in order, assist with payment plan setup and penalty remission requests if appropriate.
- Prevention: simple monthly checklist and deadlines so future BAS are on time.
Where you suspect errors in earlier lodgements, use BAS Corrections or request a BAS Review before or alongside your catch‑up.
Australian context: deadlines, penalties and lodgement
- BAS reports GST, PAYG withholding and, where relevant, PAYG instalments and other labels to the ATO. Most small businesses lodge quarterly; some lodge monthly.
- Late BAS can trigger Failure To Lodge (FTL) penalties calculated in penalty units per 28‑day period (or part thereof) overdue, and general interest charges (GIC) on unpaid amounts.
- Using a registered BAS agent provides access to ATO agent portals, can assist with payment plans and, in suitable cases, request remission of some penalties.
- If payroll is involved, align Single Touch Payroll (STP) and PAYG withholding figures to avoid mismatches.
- If you are new to GST or unsure of setup, see BAS Setup before the next cycle.
What to compare before you commit
Scope
Confirm the late BAS scope covers reconciliations, error fixes, preparation and lodgement of each overdue BAS/IAS, plus ATO follow‑up.
Software fit
Ensure deep experience in your stack (Xero, MYOB, QuickBooks Online) and clarity on the exact workflow for bank rules, GST codes and payroll.
Turnaround and communication
Ask for a timeline by period, who does what, and how queries and missing documents are handled during the catch‑up.
Commercial fit
Compare fixed‑fee vs hourly for multiple late periods, inclusions/exclusions, and whether ongoing BAS lodgement is available once caught up.
Common late BAS scenarios we handle
- Quarterly BAS more than one period overdue due to cash‑flow delays.
- Change of bookkeeper/accountant with unreconciled Xero/MYOB/QBO files.
- Business purchase where prior owner’s records or ATO access are missing.
- Payroll/STP processed but PAYG W not correctly reported on the BAS.
- Mixed‑supply businesses with GST‑free and taxable items coded incorrectly.
- Fuel tax credits, WET or LCT incorrectly treated and needing correction.
If your situation is different, outline it in the form below and we will map the right path—whether that is BAS catch‑up, a deeper BAS review, or steady‑state lodgement.
Best next steps
List each overdue BAS period, choose the accounting file you will use going forward, and gather bank statements and key invoices. That reduces back‑and‑forth and speeds up lodgement.
If you expect to owe GST or PAYG, prepare a simple cash‑flow view so a realistic ATO payment plan can be set up immediately after lodgement.
If you are unsure whether you need corrections first, read BAS Corrections and BAS Review, or ask for guidance below.
Frequently asked questions
What does late bas usually involve?
Late BAS help covers ATO checks, bookkeeping catch‑up, GST/PAYG reconciliations, error fixes, preparing and lodging each overdue BAS/IAS, and ATO follow‑ups like payment plans and penalty remission where appropriate.
How do I know if this service suits my business?
Choose late BAS support if one or more BAS are overdue, you have ATO reminders or debt, your file is unreconciled, you changed providers, or you took over a business with missing records. If you are current but want a check, use a BAS Review; if you only need ongoing lodgements, use BAS Lodgement.
What should I compare before choosing a provider?
Check BAS agent registration, software expertise, turnaround on multiple periods, fixed vs hourly pricing, inclusions (reconciliations, corrections, ATO calls), and help with penalty remission and payment plans.
What should I read next?
For catch‑ups see BAS Catch Up Services. For error fixes see BAS Corrections or a BAS Review. For regular filings, go to BAS Lodgement. If you are new to GST, read BAS Setup.