Key takeaways
Billing software falls into a handful of core models – recurring (subscription), usage-based, one-off and hybrid – plus industry-specific variants for trades and professional services.
Australian small businesses were paid an average of 6 days late in the June 2026 quarter, and late payments cost the average small business A$15,257 over the last financial year¹.
Airwallex Billing covers invoicing, subscriptions and usage-based billing from one platform, built for Australian businesses trading locally and overseas.
Late payments continue to contribute to cash flow challenges for Australian small businesses. Data from Xero shows clients take an average of 22.9 days to pay an invoice, and late payments are costing small businesses over $15,000 over the past financial year¹. Choosing the right type of billing software remains an important decision.
The main types of billing software are recurring (subscription) billing, usage-based billing, one-off billing, hybrid billing and multi-entity billing. On top of these core models, many tools are built for specific industries, such as construction, transport, electrical trades and legal services.
Understanding the types of billing software helps you narrow the field quickly. The right fit depends on how you charge customers, what industry you work in, and whether you bill only in Australian dollars or in multiple currencies. This guide breaks down each model, what to look for by industry, and how to choose a tool that handles GST correctly.
What are the main types of billing software?
There are five common billing software categories: recurring, usage-based, one-off, hybrid and multi-entity. The first four describe how customers are charged; multi-entity billing describes how billing is managed across entities.
Type | How it works | Best for | Example use case |
|---|---|---|---|
Recurring (subscription) billing | Charges a fixed amount on a set schedule – weekly, monthly or annually – using subscription management tools | SaaS companies, memberships, retainers | A software company charging A$49 per user each month |
Usage-based (metered) billing | Tracks what each customer consumes and charges accordingly, using usage-based billing meters | Cloud, API and data platforms, utilities, logistics | An API provider charging per 1,000 calls |
One-off (transactional) billing | Creates a single invoice per job, sale or project through standard invoicing | Tradies, consultants, wholesalers | An electrician invoicing for a switchboard upgrade |
Hybrid billing | Combines two or more models, such as a base subscription plus usage charges | Growing businesses with tiered or flexible pricing | A platform charging a monthly fee plus overage for extra storage |
Multi-entity billing capability | Centralises invoicing and collections for several legal entities or brands in one system | Groups with subsidiaries in multiple countries | An Australian parent company billing through its NZ and UK entities |
Businesses may end up using more than one model. A software company might pair subscriptions with metered billing for heavy users, while tracking monthly recurring revenue (MRR) to measure growth. If your pricing is likely to change as you scale, choose billing software that supports several models rather than locking you into one.
Which billing software suits your industry?
The best billing software for your industry is one that matches how you price and deliver work. A tradie invoicing from the job site needs different features from a law firm tracking billable hours, so industry-specific tools focus on the details generic software can miss. Below are five common categories, what each typically involves, and the features worth prioritising.
Transport billing software
Transport and logistics businesses often bill for irregular jobs, with charges based on distance, fuel, weight or waiting time. A single delivery can also involve several parties – the shipper, the receiver and a freight broker – each needing their own invoice. Because margins are tight and fuel costs move week to week, the software should make it easy to update rates without rebuilding every invoice template.
What to look for in transport billing software:
Line items for mileage, fuel levies and surcharges
Multiple invoice recipients per job
Batch invoicing for high job volumes
Construction billing software
Construction projects are usually billed in stages rather than as one lump sum. Progress claims, retention amounts (a percentage held back until the work is complete) and subcontractor invoices all need to be tracked against the same project. Getting this wrong can hold up cash flow for months, so construction billing software should show exactly what's been claimed, paid and still held back on each job.
What to look for in construction billing software:
Milestone or progress billing
Retention tracking and release
Subcontractor invoice management with project-level reporting
Electricians billing software
Electricians need to move from quote to invoice quickly, often while still on site. Invoices typically combine labour, call-out fees and parts, so each line item needs to be clear and GST calculated correctly. The faster the invoice goes out, the sooner the payment clock starts, which is why mobile-first tools are popular with sparkies running their own business.
What to look for in electricians billing software:
One-click quote-to-invoice conversion
Mobile invoicing so you can bill before leaving the job
Saved price lists for parts and labour
Legal billing software
Many law firms bill by time, but fixed-fee, milestone and mixed arrangements are also common. Legal billing software should capture billable hours accurately when time-based billing applies and link them to the correct matter. Where a firm holds client money, it may also need trust-accounting workflows aligned with the rules in the relevant state or territory. Matter-based invoicing can make fees easier for clients to review.
What to look for in legal billing software:
Time tracking with hourly rates by lawyer or task
Matter-based invoicing
Trust accounting and compliant record-keeping
Client billing software
Consultants, agencies and other professional services firms often juggle retainers, fixed-fee projects and hourly work across many clients at once. Client billing software keeps each arrangement separate while giving you one view of what's owed. As your client list grows, automation like recurring retainer invoices and payment reminders stops billing from eating into billable time.
What to look for in client billing software:
Recurring invoices for retainers
Project-based and milestone billing
A dashboard showing outstanding invoices across all clients
How to choose the best billing software for your business
The best billing software for your business is one that fits how you charge and collect payments. Look for applicable GST handling, support for the currencies you bill in, and features suited to your business size. Before comparing options, check each one against these criteria; they apply to many Australian businesses, regardless of size.
GST handled on taxable supplies: The software should calculate and display applicable GST – generally 10% for taxable supplies – and show GST separately or use the statement "Total price includes GST" only when the GST amount is exactly one-eleventh of the total price, in line with ATO requirements.
Clean data for BAS, not BAS lodgement: Billing software isn't a substitute for lodging a business activity statement (BAS). It should provide accurate, GST-tagged data to accounting software or an adviser for reconciliation and lodgement as appropriate.
Multi-currency invoicing and settlement: If you bill overseas clients, look for a platform that can invoice and settle in your customer's currency, without forcing a conversion at the point of payment. That lets you choose when to convert funds, rather than accepting whatever rate applies on the day your customer pays.
Local payment methods, not just cards: Customers in different regions prefer varying payment methods. For example, Australians favour cards and BPAY over cash. Offering the payment method your customer already prefers is one of the simplest ways to reduce late payments.
Accounting integration, with a clear line on what it does: Check whether a tool syncs payment records, invoices, subscriptions or only selected objects into your accounting software, such as Xero. Billing software should complement, not replace, the accounting system responsible for tax and BAS workflows.
Automation that reduces admin: Recurring invoices, automated reminders and dunning (automatic retries for failed payments) cut hours of manual follow-up. This matters most for subscription payment processing, where a failed card payment can turn into lost revenue.
Best billing software for small businesses
The best billing software for small businesses is quick to set up, competitively priced, and covers the GST and BAS basics without extra configuration. When comparing small business invoice software, prioritise:
No-code setup that is simple and easy to manage without tech support
Low, transparent fees
Mobile invoicing for billing on the go
Support for Australian tax-invoice fields and clean, GST-tagged data for BAS workflows
Online payment links
Best billing software for enterprise
The best billing software for enterprise supports multiple entities, currencies and systems at scale, on top of the core criteria for every Australian business. Larger organisations often bill across regions, brands and pricing models at once, so flexibility and control matter as much as ease of use. Prioritise:
Multi-entity support from a single account
Multi-currency billing and settlement at high volumes
ERP and CRM integration, plus API access for custom workflows
Detailed audit trails and approval controls
Support for hybrid and usage-based pricing
A dedicated account manager for support
How Airwallex simplifies billing for Australian businesses
Airwallex Billing brings invoicing, subscription management and usage-based billing into one platform, so you can charge customers however your pricing works – one-off, recurring or by usage. You can also manage billing across multiple business entities from a single organisation, with no code needed to create invoices and subscriptions.
It's built for Australian businesses that bill locally and overseas, and want to collect payments without juggling separate tools for each market.
Bill globally, get paid locally: Create invoices in 130+ currencies and let customers pay using 160+ local payment methods, including cards, bank transfers and digital wallets.
Avoid forced conversions: For supported invoice-payment currencies and methods, receive like-for-like settlement in the original invoice currency, then hold funds in your Airwallex account to pay suppliers and expenses.
Automate collections: Schedule invoices to send automatically, set reminders for overdue invoices, and let failed payments retry automatically. Payments reconcile against invoices in real time.
Stay on top of GST: Make sure every invoice you send includes the details the ATO requires – our guide to tax invoice requirements covers what each tax invoice needs.
Frequently asked questions
What are the three types of billing?
Billing is commonly grouped into three types: one-off (transactional) billing, recurring (subscription) billing and usage-based billing. One-off billing charges once per job or sale, recurring billing charges a set amount on a schedule, and usage-based billing charges for what a customer actually consumes. Hybrid models combine two or more.
What is the best billing software?
The best billing software is the one that matches your pricing model, industry and business size. For Australian businesses, look for support for applicable GST calculations and tax-invoice fields, local payment methods such as bank transfer, accounting integration with a clear sync scope, and automated reminders. If you bill overseas clients, multi-currency invoicing matters too.
What billing software is best for small businesses?
The best billing software for small businesses is simple to set up, has transparent fees and supports mobile invoicing. It should support Australian tax-invoice fields, GST-tagged data for BAS workflows, bank transfers and cards, and an accounting integration whose sync scope you have confirmed. Automated reminders can help you follow up on overdue invoices.
What billing software is best for enterprise?
The best billing software for enterprise supports multiple entities, multi-currency billing at scale and integration with ERP and CRM systems. Look for detailed audit trails, approval controls and support for complex pricing, such as hybrid and usage-based models. API access helps finance and engineering teams automate billing across markets.
Sources
This information doesn’t take into account your objectives, financial situation, or needs. If you are a customer of Airwallex Pty Ltd (AFSL No. 487221) read the Product Disclosure Statement (PDS) for the Direct Services available here.
The Airwallex Editorial Team
Airwallex’s Editorial Team is a global collective of business finance and fintech writers based in Australia, Asia, North America, and Europe. With deep expertise spanning finance, technology, payments, startups, and SMEs, the team collaborates closely with experts, including the Airwallex Product team and industry leaders to produce this content.
