Understanding Input Tax Credits and Asset Use

When your business buys an asset and pays GST on that purchase, you may be eligible to claim an input tax credit (ITC). This credit lets you recover the GST paid, as long as the asset is used in your business for taxable purposes. However, what happens if the use of that asset changes over time? Maybe it becomes partly for private use, or it shifts to a fully taxable business purpose. In such cases, you may need to adjust your original ITC claim.

The ATO requires businesses to monitor the use of assets over time and make adjustments when that use changes. This ensures that GST credits reflect the actual extent of business use. These rules generally apply to higher-value assets that are subject to longer-term use, such as vehicles, machinery or buildings.

What Triggers an Adjustment?

An adjustment is triggered when there is a change in the extent of creditable use. This means the proportion of the asset used for taxable business purposes changes compared to what you originally claimed. For example, if you originally used a vehicle 100% for business but later begin using it 30% for private trips, the ATO requires you to adjust your ITC.

Conversely, if an asset that was initially only partially used for business becomes fully used in taxable activities, you may be entitled to claim an additional credit. This can help recover more of the GST originally paid, as your usage has shifted in favour of business activity.

How Adjustment Periods Work

Not every change in use requires an adjustment. The rules only apply to assets that meet the criteria for adjustment periods. The number of adjustment periods depends on the nature and value of the asset:

• For most tangible assets worth $5,000 or more (excluding GST), there are up to five adjustment periods.

• For real property (like buildings), there can be up to ten adjustment periods.

• For intangible assets, the adjustment period rules are different and often shorter.

The adjustment periods begin in the financial year the asset is first used or installed ready for use, and each subsequent year counts as a new adjustment period. If the change in use happens within this window, an adjustment is needed.

Calculating the Adjustment Amount

To determine the adjustment, you compare the actual use during the adjustment period to the use you originally estimated. If the new use is lower, you’ll need to repay part of the ITC. If it’s higher, you may claim more.

The formula generally follows:

Adjustment = (Actual Use % – Estimated Use %) x Full ITC x 1 / Number of Adjustment Periods

Let’s say you purchased equipment for $11,000 (including $1,000 GST) and claimed the full $1,000 GST based on 100% business use. Two years later, it’s only used 60% for business. The adjustment would be:

(60% – 100%) x $1,000 x 1/5 = -$80

This means you must repay $80 of your original credit in your next BAS.

Reporting Adjustments in Your BAS

Adjustments are reported in the G7 (Adjustments) and 1A/1B fields of your Business Activity Statement (BAS). If the adjustment is a credit increase, it goes to 1B; if it’s a decrease (you’re repaying GST), it goes to 1A.

You’ll need to keep detailed records that support your revised usage estimates. This includes mileage logs, work diaries, or other evidence showing how the asset is now used.

Examples of Common Scenarios

Here are some examples where adjustment obligations might arise:

• Company vehicle becomes partly private: You claimed full ITC on purchase, but later the vehicle is also used by an employee for personal errands. You must adjust to reflect the new split.

• Equipment use increases: You initially used machinery 50% for business and claimed half the GST. A few years later, it’s used exclusively in your workshop. You can adjust and claim the remaining 50% of the ITC.

• Leased property changes purpose: A warehouse previously rented to a GST-registered business is now rented to a GST-exempt charity. This change in use will affect your ITC entitlement.

Simplifying Adjustments with Apportionment Methods

The ATO allows businesses to use reasonable apportionment methods to calculate business vs private use. This could be based on floor space, hours used, revenue generated, or any other fair basis.

Once you establish your apportionment method, stick with it unless a major change occurs. Consistency helps reduce audit risk and simplifies ongoing reporting.

For vehicles, a commonly accepted method is using a logbook over 12 weeks to determine business use. This percentage can then be used across adjustment periods unless there’s a significant change.

Record Keeping Requirements

You must retain documents for five years after the end of the adjustment period in case of ATO review. Key documents include:

• Purchase invoices with GST breakdown

• Logbooks or usage logs

• Diaries or rosters showing business use

• Annual calculations and adjustment records

Good recordkeeping not only ensures compliance but also helps you maximise your GST entitlements without fear of penalties.

When No Adjustment Is Needed

There are situations where no adjustment is required, such as:

• The asset’s value is below the adjustment threshold

• The change in use is minor and falls within acceptable variance

• The adjustment period has already ended

Always refer to the ATO’s current rules and tolerances. If in doubt, seek advice from a registered BAS agent or tax advisor.

Final Thoughts

Adjusting your input tax credits isn’t just a compliance obligation, it’s also an opportunity to claim the correct amount of GST and avoid giving too much back to the ATO. Monitor your asset usage over time and be proactive about adjustments. Doing so ensures your GST claims reflect the real business benefit, and helps you stay on the right side of the tax office.

In a changing business environment, flexibility is key, but so is accuracy. When you adjust your operations, don’t forget to adjust your GST claims too.