Published: 8 April 2026 | FY 2025-26

Phone Bill Tax Deduction: How to Claim Work-Related Phone Expenses in Australia

If you use your phone for work purposes, you could be missing out on valuable tax deductions every year. Whether you're making business calls from your mobile, receiving work calls on your home landline, or using your phone to stay connected with clients, the Australian Taxation Office (ATO) allows you to claim the work-related portion of your phone expenses. Understanding how phone bill tax deductions work can put more money back in your pocket at tax time.

Many Australian workers are uncertain about what they can claim and how to calculate their work-related percentage correctly. Some overclaim and risk ATO scrutiny, while others underclaim and miss out on legitimate deductions. This comprehensive guide explains everything you need to know about claiming phone bill tax deductions for the 2025-26 financial year, including the rules for both mobile and home phone expenses, calculation methods, and essential record-keeping requirements. To see how these deductions could improve your overall tax position, try our take-home pay calculator before we explore the details.

What Phone Expenses Can You Claim?

The ATO allows you to claim a deduction for the work-related portion of your phone expenses, provided you paid for the costs yourself and were not reimbursed by your employer. This applies to both employees and self-employed individuals, though the specific documentation requirements may vary. The fundamental principle is that you can only claim expenses that relate directly to earning your assessable income.

For mobile phone expenses, you can claim the work-related portion of your monthly plan fees, handset costs (if purchased outright), accessories, repairs, and work-specific app subscriptions. If you use your personal mobile for work calls, emails, or accessing work applications, you can claim a percentage of these costs. For home phone expenses, you can claim the cost of work-related calls made from your landline, though you'll need to itemise these separately from your regular service fees.

It's important to understand that you cannot claim any portion of your phone use that is private. This includes personal calls to family and friends, social media use for entertainment, streaming services, and any other non-work-related activities. The ATO requires you to apportion your expenses between work and private use, and you must be able to demonstrate how you calculated this split if asked.

How to Calculate Your Work-Related Phone Percentage

To claim phone bill tax deductions, you need a reasonable basis for determining what percentage of your phone use is work-related. The ATO accepts several calculation methods depending on your circumstances and the type of phone you use:

For mobile phones: The most common approach is keeping a representative four-week diary. Record every call and data usage session, noting whether it was work or personal, then calculate the percentage. This percentage can then be applied to your annual phone costs. Alternatively, if you receive itemised bills, you can identify specific work-related calls and data sessions to calculate an exact proportion.

For home phones: Since most home phone plans don't provide itemised billing, you'll need to keep a diary for a representative four-week period. Record the number of work calls versus personal calls you make and receive, along with an estimate of call duration. If you have an itemised bill, you can use actual call records to determine your work percentage more precisely.

ATO Phone Deduction Rules for FY 2025-26

The ATO has specific requirements for claiming phone expenses that you must follow to ensure compliance. For the 2025-26 financial year, these rules remain consistent with previous years, but it's important to stay up to date with any changes.

If you're claiming phone handset costs, the rules depend on the purchase price. Phones costing $300 or less can be claimed as an immediate deduction in the year of purchase (to the extent of work-related use). For phones costing more than $300, you must depreciate the asset over its effective life, which the ATO typically considers to be 2-3 years for mobile phones. You'll claim the work-related portion of the depreciation each year.

For ongoing phone plan fees, you can claim the work-related percentage of your monthly costs. This includes post-paid plans, pre-paid recharges, and any excess usage charges that were work-related. If you have a phone and internet bundle, you'll need to apportion the bundle cost between services before applying your work-related percentage to the phone portion.

The ATO allows the simplified method for phone claims under $50 in total expenses without detailed records. However, given that most phone plans cost significantly more than this monthly, proper record-keeping is strongly recommended. The small investment of time in keeping a four-week diary can yield substantial returns at tax time.

Claiming Mobile Phone Expenses

Mobile phones are essential for many Australian workers, and the ATO recognises this by allowing deductions for work-related use. Understanding what you can claim and how to document it properly will help you maximise your deduction while staying compliant.

Work-related mobile use includes calls to clients, colleagues, and suppliers; work emails and messaging; accessing work documents and cloud storage; using work-related applications; and researching information for your job. If you're on-call for your job and need to keep your phone available, a portion of your costs may also be deductible even when you're not actively using it.

When claiming mobile phone expenses, you can include monthly plan fees, handset purchase costs (immediate deduction if $300 or less, or depreciation if more), accessories like cases and chargers (work-related portion), repairs for work-related damage, and subscriptions to work-specific apps and services. If an app or service is used exclusively for work, you can claim 100% of the cost. If it's used for both work and personal purposes, apply your work-related percentage.

To understand how mobile phone deductions fit into your broader tax picture, you might also want to explore other work-related expenses you can claim. Our guide on what you can claim on tax provides a comprehensive overview of available deductions.

Claiming Home Phone (Landline) Expenses

While mobile phones dominate modern communication, many Australians still maintain home phone lines, and these can also generate tax deductions if used for work purposes. The rules for home phones differ slightly from mobile phones due to the nature of landline billing.

For work-related home phone calls, you can claim the cost of calls made for work purposes. This includes calls to clients, conference calls, and other business-related communications. You can claim either the actual cost of work calls (if itemised) or use a reasonable estimate based on your four-week diary. The connection fee or line rental portion of your bill is generally not deductible unless you can demonstrate that the line is used exclusively or primarily for work.

To calculate your home phone work percentage, keep a diary for four representative weeks recording the number of work calls versus personal calls, along with estimated durations. If your calling patterns vary throughout the year (for example, busy periods with more client contact), consider keeping multiple diaries to capture different usage patterns. Apply the calculated percentage to your annual phone costs to determine your deduction amount.

Record-Keeping Requirements for Phone Deductions

Proper record-keeping is essential for substantiating your phone bill tax deduction claims. The ATO can review your claims for up to five years after you lodge your tax return, so maintaining accurate documentation is crucial.

For all phone claims, keep your phone bills for at least five years. Electronic copies are acceptable, so saving PDFs or screenshots of online bills is sufficient. If you use the diary method to establish your work-related percentage, retain your four-week representative diary alongside your calculations. The diary should show dates, times, descriptions of work use, and the final percentage calculation.

If you're claiming depreciation on a phone costing more than $300, keep the purchase receipt showing the date and cost. You'll also need to document your depreciation calculations each year. For work-specific subscriptions and apps, keep receipts or email confirmations of payment. The ATO's myDeductions tool in the ATO app can help you track these expenses throughout the year, making tax time much easier.

If your circumstances change significantly during the year—such as starting a new job with different phone requirements or switching to working from home—consider keeping an updated diary to reflect the new usage pattern. This documentation will support any variations in your claimed percentage from year to year.

How Phone Deductions Affect Your Tax Position

Understanding how phone bill tax deductions impact your overall tax helps you make informed decisions about claiming strategies. These deductions reduce your taxable income, which in turn reduces the amount of income tax you pay. The exact value of a deduction depends on your marginal tax rate.

For the 2025-26 financial year, Australia's individual income tax rates determine the value of your deductions:

Note: The above rates do not include the 2% Medicare levy, which also applies to most taxpayers. Higher income earners may also pay the Medicare Levy Surcharge without private health insurance.

It's important to note that while phone deductions reduce your taxable income, they don't reduce your income for all purposes. If you have a HECS-HELP debt, the ATO calculates repayment income by adding back certain deductions, including work-related expenses. This means claiming phone expenses won't reduce your compulsory HECS repayments. Similarly, the Medicare Levy Surcharge and some family tax benefit calculations use income figures that may not reflect your work-related deductions.

Common Mistakes to Avoid

The ATO closely monitors work-related expense claims, and phone deductions are frequently reviewed because they're commonly overclaimed. Avoid these common mistakes to stay compliant:

Claiming 100% work use without justification: Unless you have a dedicated work phone used exclusively for employment purposes, claiming 100% of your phone costs is likely to trigger ATO attention. Most people use their phones for personal calls, social media, and entertainment. Be realistic about your work percentage and keep records to support your claim.

Failing to keep adequate records: Simply estimating your work use percentage isn't sufficient. The ATO requires evidence of how you calculated your claim. Keep a diary for four representative weeks or use itemised bills to identify work usage. Update your records annually if your usage patterns change.

Double-dipping with employer reimbursements: If your employer reimburses you for phone expenses or provides a phone allowance, you cannot claim those same costs as deductions. The allowance is taxable income, and you can only claim actual out-of-pocket expenses. Check your pay slips to ensure you're not claiming reimbursed amounts.

Claiming capital costs incorrectly: Phones costing more than $300 must be depreciated rather than claimed as an immediate deduction. Don't claim the full cost of an expensive phone in the year of purchase. Similarly, don't forget to continue claiming depreciation in subsequent years for phones you're still using for work.

Frequently Asked Questions

Can I claim my entire phone bill if I use it for work?

No, you can only claim the work-related portion of your phone expenses. You must apportion costs between work and private use. Unless you have a dedicated work phone used exclusively for business, claiming 100% is not permitted and may trigger ATO scrutiny.

How do I calculate my work-related phone percentage?

Keep a diary for four representative weeks recording your phone usage. Note whether each call or data session is work or personal, then calculate the percentage of work use. Apply this percentage to your annual phone costs. Alternatively, use itemised bills to identify actual work-related usage.

Can I claim phone expenses if I work from home?

Yes, if you use your phone for work purposes while working from home, you can claim the work-related portion. Phone expenses are claimed separately from home office deductions. The ATO's fixed rate method for home office expenses does not include phone costs.

What records do I need to keep for phone deductions?

Keep phone bills for five years, a four-week representative diary showing work percentage calculations, and receipts for handset purchases or repairs. For phones over $300, keep purchase receipts and depreciation schedules. Electronic records are acceptable.

Can I claim a new phone purchase on my tax return?

Yes, if you purchased a phone for work use, you can claim the work-related portion. If the phone cost $300 or less, claim it immediately. If it cost more than $300, depreciate it over 2-3 years, claiming the work-related portion of depreciation each year.

Conclusion

Phone bill tax deductions offer Australian workers a valuable opportunity to reduce their taxable income and increase their tax refund. For the 2025-26 financial year, remember these key points: you can only claim the work-related portion of your phone expenses; keep a four-week representative diary or use itemised bills to calculate your work-related percentage; phones costing $300 or less can be claimed immediately, while more expensive phones must be depreciated; and maintain records for five years to support your claims.

Whether you use a mobile phone, home phone, or both for work purposes, understanding the ATO's rules ensures you claim correctly and maximise your legitimate deductions. Remember that phone deductions reduce your taxable income but don't reduce income for HECS-HELP repayment calculations or Medicare Levy Surcharge purposes.

To estimate how phone bill tax deductions and other work-related expenses could affect your tax position, use our income tax calculator and take-home pay calculator. These free tools help you understand your tax liability, explore different deduction scenarios, and plan your finances for the 2025-26 financial year. Always consult a registered tax agent if you're unsure about your specific circumstances.

Disclaimer: Tax rates are subject to change. Always verify current rates and rules with ATO.gov.au. This information is general in nature and does not constitute professional tax advice.