If you are expanding your business across borders, you already know that growth is exciting. However, with that growth comes a shadow that follows every sale: tax compliance. Whether you are running a fast-growing USA LLC from abroad, a Canadian corporation, or an Australian entity, the rules of “Sales Tax Nexus” are the invisible boundaries that determine whether you owe money to a local government.
At Sterlinx Global, we see business owners get overwhelmed by the sheer variety of rules. One state wants a percentage after your 200th transaction; another country wants a cut the moment you hit a specific dollar amount. It can feel like a moving target.
This guide is your roadmap. We are going to break down exactly what nexus is, how it triggers in the USA, Canada, and Australia, and: most importantly: how we help you handle the filings so you can focus on your next big move.
Understanding the “Nexus” Concept: Why It Matters to You
In the simplest terms, nexus is the legal connection between your business and a taxing jurisdiction. Before a state or country can require you to collect and remit sales tax, you must have a “nexus” there.
Years ago, this usually meant you needed a physical office or a warehouse. Today, in our digital-first world, nexus is much broader. You can trigger tax obligations without ever setting foot in a specific region.
Ignoring these triggers isn’t an option. Failing to register and file can lead to back taxes, hefty interest, and penalties that can wipe out your profit margins. This is why staying ahead of the curve is essential for your global expansion.
The United States: Navigating the 50-State Maze
The USA is arguably the most complex landscape for sales tax. There is no national sales tax; instead, there are 45 states (plus D.C.) that each have their own rules. For a USA LLC or an international brand selling into the States, you need to watch out for two main types of nexus.
1. Physical Nexus
This is the traditional form. You have physical nexus if you have:
- An office or place of business.
- Employees or independent contractors working in the state.
- Inventory stored in a warehouse (including Amazon FBA centers).
- Ownership of real or personal property.
2. Economic Nexus
Following the landmark South Dakota v. Wayfair ruling, states can now tax you based solely on your economic activity. Even if you are based in London or Sydney, if you sell enough to customers in a specific US state, you have nexus.
Most states use a threshold of $100,000 in gross sales or 200 separate transactions in a calendar year. However, every state is different. Some have eliminated the transaction count, while others have higher dollar thresholds.
Marketplace Facilitator Laws
If you sell through platforms like Amazon, Walmart, or eBay, these “marketplaces” are often required to collect and remit the tax for you in most states. However, this does not always mean you are off the hook. You may still need to register for a sales tax permit and file “zero returns” to show the state that the tax was collected by the facilitator.
Pro-tip: Registering for a sales tax permit before you hit the threshold in high-volume states can save you from a retrospective tax bill that you forgot to collect from your customers.
Canada: GST, HST, and the $30,000 Rule
Moving north, the Canadian system is a mix of federal and provincial taxes. If you are selling to Canadian customers, you are dealing with the Goods and Services Tax (GST), and in some provinces, the Harmonized Sales Tax (HST).
The “Small Supplier” Threshold
In Canada, the magic number is usually $30,000 CAD. If your worldwide taxable revenue exceeds this amount over four consecutive calendar quarters, you are no longer a “small supplier.” You must register for a GST/HST account with the Canada Revenue Agency (CRA).
Provincial Variations (PST and QST)
While many provinces use the HST (a combined federal and provincial rate), some: like British Columbia, Saskatchewan, and Manitoba: maintain their own Provincial Sales Tax (PST). Quebec has the Quebec Sales Tax (QST).
Staying compliant in Canada means:
- Monitoring your total sales globally.
- Identifying which province your customer is in.
- Applying the correct rate (ranging from 5% to 15%).
Doing this manually is a recipe for disaster. This is why Sterlinx Global provides a full-suite compliance service for Canada, ensuring your CRA filings are accurate and on time. You can keep track of regulatory changes via our Canada Updates (CRA) section.
Australia: GST and the ATO
For those expanding into the Australian market, the Australian Taxation Office (ATO) oversees the Goods and Services Tax (GST).
The $75,000 Threshold
You are required to register for GST if your business has a GST turnover of $75,000 AUD or more. This applies to both local Australian entities and international businesses selling to Australian consumers.
Low-Value Imported Goods
If you sell physical goods valued at $1,000 AUD or less to consumers in Australia, and you meet the $75,000 threshold, you must collect GST at the point of sale.
The ATO is quite strict about these digital and imported goods rules. If you are unsure where you stand, check the latest Australia Updates (ATO) to stay informed on any threshold adjustments for 2026.
How Sterlinx Global Simplifies Your Global Compliance
We aren’t just a traditional tax advisory firm. Sterlinx Global operates as a Global Tax Compliance Suite. We know that as a business owner, you don’t want “advice” that leaves you with more work; you want the work done.
The Sterlinx Operating Model: You Provide Data, We Deliver Compliance
Our process is designed to take the weight off your shoulders:
- Data Integration: We pull your sales data directly from your marketplaces or accounting software.
- Calculation: We determine exactly where you have triggered nexus (USA, Canada, or Australia).
- Registration: We handle the paperwork to get your tax permits and GST/HST numbers.
- Ongoing Filings: We prepare and file your returns on a recurring basis (monthly, quarterly, or annually).
- Bookkeeping Synergy: Because we also handle bookkeeping, your tax filings always match your financial records, ensuring total consistency for year-end accounts.
Why Choose a Compliance Suite Over an Advisor?
A consultant will tell you that you might have nexus. We tell you that you do have nexus, and then we file the return for you. It’s an end-to-end delivery model that prioritizes operational execution. Whether you are managing a UK Limited Company with US sales or an Australian entity expanding into the EU (where we provide VAT-only services), we provide a single point of contact for your global tax needs.
Your 2026 Compliance Checklist
To stay on the right side of the law this year, follow this simple checklist:
- Review Sales Data: Look at your last 12 months of sales by region. Have you crossed the $100k (USA), $30k (CA), or $75k (AU) thresholds?
- Check Inventory Locations: If you store goods in any US state, Canadian province, or Australian warehouse, you likely have physical nexus.
- Verify Marketplace Status: Confirm whether Amazon, eBay, or other platforms are collecting tax on your behalf.
- Register Proactively: Don’t wait until you’ve missed a filing deadline. Register for permits and accounts as soon as you know you have nexus.
- Set Up Ongoing Reporting: Whether through Sterlinx Global or another provider, ensure you have a system in place to file returns accurately and on time.
