Quarterly BAS Checklist for Mornington Peninsula Businesses

BAS time shouldn't be stressful, but for many Mornington Peninsula business owners, it's a quarterly headache. The good news? With the right checklist and preparation, you can make BAS lodgement smooth and straightforward.

I'm Linda from In Addition Bookkeeping, and after years of preparing BAS for clients across Victoria, I've developed a systematic approach that takes the stress out of lodgement. Let me share my quarterly BAS checklist so you can stay compliant and confident.

Before You Start Your BAS

The secret to easy BAS lodgement isn't what you do on lodgement day. It's what you do in the weeks leading up to it. Here's my pre-lodgement ritual that I recommend to all my clients:

Start early. Don't wait until the last week of the quarter. Begin your BAS preparation at least two weeks before the deadline. This gives you time to find missing receipts, chase up paperwork, and fix any errors you discover.

Get your bookkeeping current. Your BAS is only as accurate as your books. Make sure every transaction for the quarter is recorded before you start calculating your BAS figures. If you've fallen behind, catch-up bookkeeping services can get you back on track quickly.

Review your accounting system. Check that all transactions are coded correctly with the right GST treatment. One misclassified transaction can throw off your entire BAS.

Gather supporting documents. Have your bank statements, invoices, receipts, and payment summaries ready to reference. Good expense tracking throughout the quarter makes this step much easier.

Linda's Tip: I always do a "sanity check" before starting any BAS. I look at the total sales and expenses for the quarter and ask myself: does this make sense compared to last quarter and last year? If something looks wildly different, there's usually a coding error or missing transactions.

Key Documents to Review

Before you lodge your BAS, you need to review several key documents to ensure everything is accurate and complete.

Bank Reconciliations

This is non-negotiable. Your bank reconciliations must be complete and up to date for the entire quarter. Every bank account and credit card should be reconciled right through to the last day of the quarter.

Why? Because unreconciled accounts hide errors. You might have duplicate transactions, missing entries, or incorrect amounts. These errors flow directly into your BAS and can cause serious compliance issues.

Linda's Tip: When I reconcile accounts, I don't just match the balances. I scan through the transactions looking for anything unusual: round numbers that might be estimates, large transactions I don't remember, or unfamiliar payees. These often reveal errors that need fixing.

Sales Records

Review all your invoices and sales for the quarter:

• Check that every sale is recorded

• Verify GST has been calculated correctly

• Ensure export sales are treated correctly (GST-free)

• Confirm any GST-free or input-taxed sales are coded properly

• Review any credit notes or refunds

Purchase Records

Go through your expenses and purchases:

• Verify you have valid tax invoices for GST claims over $82.50

• Check that supplier ABNs are recorded

• Ensure imported goods and services are treated correctly

• Review any private or non-deductible expenses

• Confirm capital purchases are coded separately

Payroll Records

If you have employees, review:

• PAYG withholding amounts

• Superannuation obligations

• Fringe benefits (if applicable)

• Any termination payments

If payroll feels overwhelming, professional payroll processing services can ensure accuracy and STP compliance.

Financial Statements

Run your financial statements for the quarter. Your Profit & Loss and Balance Sheet will help you spot errors:

• Do revenue and expenses look reasonable?

• Are there any unusually large or small figures?

• Do account balances make sense?

• Are there any negative balances in accounts that shouldn't have them?

Linda's Tip: I always compare the current quarter to the same quarter last year. If sales are dramatically different without a clear reason (like seasonal variation or business growth), I dig deeper to find out why.

Lodgement Deadlines

Missing your BAS deadline isn't just inconvenient. It can result in penalties and interest charges. Here are the standard quarterly lodgement deadlines for Victoria:

• Quarter 1 (July-Sept): 28 October

• Quarter 2 (Oct-Dec): 28 February

• Quarter 3 (Jan-Mar): 28 April

• Quarter 4 (Apr-Jun): 28 July

Note that if you lodge through a registered BAS agent, you may have access to extended lodgement dates. This is one of the benefits of professional BAS and GST services.

Linda's Tip: I recommend aiming to have your BAS ready a week before the deadline. This gives you breathing room if the ATO portal has issues, if you need to make a payment arrangement, or if you discover last-minute errors that need fixing.

ATO Reminders and Support

The ATO does send reminders, but don't rely on them. Sometimes they arrive late or go to spam. Set up your own calendar reminders at:

• Start of the last month of each quarter (reminder to get books current)

• Two weeks before lodgement (start BAS preparation)

• One week before lodgement (final checks and lodgement)

The ATO also offers a BAS agent portal and several support resources, but accessing these effectively often requires professional assistance.

Common BAS Errors

After preparing hundreds of BAS returns, I've seen the same mistakes pop up again and again. Here are the most common errors and how to avoid them:

Error #1: Incorrect GST codes. This is the biggest one. Applying 10% GST when something should be GST-free, or claiming input tax credits on things that aren't eligible. Common culprits include:

• Employee reimbursements coded as purchases

• Private expenses mixed with business expenses

• Entertainment expenses (which have special rules)

• Motor vehicle expenses for private use

Error #2: Missing transactions. Incomplete records lead to incorrect BAS. This includes:

• Cash sales not recorded

• Petty cash expenses forgotten

• Credit card transactions missed

• Inter-account transfers coded as income or expenses

Error #3: Timing issues. Recording transactions in the wrong quarter affects your BAS:

• Late supplier invoices recorded in the wrong period

• Deposits recorded as income before the service is delivered

• Prepayments not handled correctly

Error #4: PAYG withholding miscalculations. Getting employee tax withholding wrong can result in penalties and unhappy employees.

Error #5: Not reconciling BAS to accounting system. Your BAS figures should tie back exactly to your accounting reports. If they don't, something is wrong.

Linda's Tip: Before I lodge any BAS, I do a final cross-check of GST codes. I run a GST detail report in the accounting software and scan for anything that looks odd. A residential rent expense showing GST? That's wrong. A staff wage showing GST? That's wrong. These quick checks catch errors before they reach the ATO.

Tools to Automate BAS

Modern accounting software has made BAS preparation much easier, but only if it's set up correctly from the start.

Xero, MYOB, and QuickBooks all have BAS reporting features built in. When your chart of accounts is properly configured with correct GST codes, these systems automatically calculate your BAS figures. Whether you use Xero bookkeeping, MYOB bookkeeping, or QuickBooks bookkeeping, proper setup is essential.

The key is in the setup:

• Every account must have the correct tax code assigned

• Products and services need default GST treatments

• Automated bank feeds should have rules that apply correct GST codes

• Regular reviews ensure nothing has been miscoded

Need help getting your system configured correctly? Accounting system setup ensures everything is structured properly from day one.

However, automation doesn't mean you can just hit "lodge" without checking. You still need to review the figures, verify they make sense, and ensure your books are complete and accurate.

This is where professional support makes a huge difference. I help clients get their systems set up right so BAS becomes a simple quarterly task rather than a quarterly nightmare.

My Complete BAS Preparation Routine

Here's the exact process I follow for every client, every quarter:

Two weeks before deadline:

1. Run bank reconciliations for all accounts

2. Review unreconciled items and follow up

3. Check for missing transactions

4. Review GST coding on major transactions

5. Verify payroll figures

6. Run preliminary BAS report

One week before deadline: 7. Complete any outstanding reconciliations 8. Run final financial statements 9. Compare quarter to previous periods 10. Generate final BAS figures 11. Cross-check GST detail report 12. Review for any unusual items 13. Prepare BAS for lodgement

On lodgement day: 14. Final review of figures 15. Lodge with ATO 16. Confirm lodgement successful 17. Schedule any payment required 18. Update client records

This systematic approach means nothing gets missed, and every BAS is lodged accurately and on time.

Get BAS Support That Makes Life Easier

If this checklist feels overwhelming, you're not alone. Many Mornington Peninsula business owners tell me they dread BAS time because there's so much to remember and check.

The good news is you don't have to do it alone. Professional BAS support means:

• No more missing deadlines or rushing at the last minute

• Confidence that your figures are accurate

• Time back in your schedule to focus on your business

• Peace of mind knowing a registered professional is handling it

Whether you need full BAS preparation or just want someone to review your work before lodgement, I'm here to help. I provide comprehensive general bookkeeping services alongside BAS support to keep your entire financial system running smoothly.

Book a free consultation and let's discuss how I can make your quarterly BAS simple and stress-free.

Linda is a registered BAS agent and qualified bookkeeper servicing the Mornington Peninsula and businesses throughout Victoria. She specialises in making BAS preparation straightforward and ensuring businesses stay compliant with ATO requirements.