A US Business Selling Into Canada: When GST/HST Registration Hits You, the Simplified vs Normal Regimes, and the Import Mechanics

US businesses meet Canadian sales tax later than they should because the instinct — we're foreign, we're fine — was retired by the digital-economy rules. The architecture now has three entry doors and a border. Door one, the simplified regime: non-resident vendors selling digital products and services to Canadian consumers (and platform operators facilitating them) must register under the simplified system once sales to unregistered Canadian recipients cross C$30,000 over twelve months — collecting GST/HST on B2C sales by the customer's province, with no input tax credits (the simplification's price) and quarterly remittance; B2B sales to GST-registered customers stay outside it on the customer's registration number, which the vendor collects and validates as its exclusion evidence. Door two, the fulfillment-warehouse rules: goods sold through Canadian warehouses — the Amazon.ca FBA pattern — put non-resident sellers into normal registration territory, and platform operators carry collection duties for third-party sales they facilitate; the US seller shipping inventory into Canadian fulfillment is in the Canadian sales tax system with the full registrant's rights and duties, input tax credits included. Door three, conventional carrying-on-business: the traditional test — soliciting plus inventory, agents, or delivery presence in Canada — pulls conventional sellers into normal registration on facts that long predate the digital rules; and voluntary registration is available below the doors for sellers who want the input credits or the commercial cleanliness. The border adds its own layer regardless of registration: imported goods pay GST at customs (plus duties per the tariff treatment), and the importer-of-record decision — customer imports (surprise fees at the door, the conversion-killing courier bill) versus seller imports as non-resident importer (seller pays border GST, recovers it through registration's input credits, and delivers landed-cost pricing) — is as much a commercial decision as a tax one, with the non-resident importer route generally winning for anyone selling at retail scale. The provincial overlay completes the map: HST provinces fold into the federal system at their blended rates; Quebec runs QST with parallel non-resident rules and its own registration; and BC, Saskatchewan, and Manitoba impose separate PSTs with their own non-resident vendor thresholds — the seller registered federally can still be unregistered where a provincial regime independently reaches them. The operating build that results: a registration map (which doors, which provinces), tax-engine configuration by province and customer type, the B2B validation workflow, importer-of-record and customs setup, and the quarterly compliance calendar — assembled once, adjusted as thresholds trip, and dramatically cheaper prospectively than retroactively, since uncollected GST/HST assessed later comes out of the seller's margin with interest.

Key takeaways

• The C$30,000 simplified-regime door: digital products and services to Canadian consumers over twelve months → register, collect by province on B2C, remit quarterly, no ITCs; B2B excluded via validated customer registration numbers.
• The warehouse door: Canadian fulfillment inventory (FBA and equivalents) → normal registration for the non-resident seller, platform collection rules for facilitated sales, full ITC access — and the inventory's import GST recovered rather than eaten.
• The conventional door and the voluntary option: carrying-on-business facts trigger normal registration; sellers below every threshold can register voluntarily for credits and cleanliness — often worthwhile the moment Canadian costs exist.
• Border GST is separate from sales GST: imports pay at customs regardless; the importer-of-record choice decides whether customers meet courier fees or sellers deliver landed pricing and recover the border tax through registration.
• Provinces are their own map: HST provinces ride the federal registration; Quebec's QST and the three PST provinces impose independent non-resident regimes with independent thresholds — the registration map is federal-plus-four, not one decision.
• Retroactive is the expensive direction: uncollected tax assesses against the seller with interest; the prospective build — registrations, engine, workflows — is a project measured in weeks and recoverable margins.

The US seller's build sequence

Threshold sweep first: trailing-twelve-month Canadian revenue split B2C/B2B, digital/goods, by province, against each regime's door. Registration second: the applicable federal regime (simplified or normal — and normal wins wherever ITCs matter), Quebec and PST provinces as their thresholds indicate. Mechanics third: tax engine rates by province and customer type; the B2B registration-number capture and validation flow; importer-of-record election and customs broker setup for goods; invoicing that shows the tax correctly. Calendar fourth: the remittance cycle, the threshold re-sweep each quarter, and the annual review where the platform's rule changes and the provinces' thresholds get re-read — because this area moves, and the build that was right at launch drifts without maintenance.

Worked example

A Texas software company and its sister goods brand both cross into Canada the same year. The software side: C$340,000 of Canadian sales — C$260,000 to businesses (registration numbers collected and validated at checkout), C$80,000 to consumers — trips the simplified regime's door on the B2C stream: simplified registration, GST/HST collected on consumer sales by province, quarterly remittances, the B2B stream documented outside the net; when Canadian contractor costs later appear, the annual review upgrades them to normal registration for the input credits. The goods side: launching on Amazon.ca with FBA inventory in Ontario and BC warehouses — normal GST/HST registration before the first shipment; the platform collects on facilitated sales per its obligations while the seller's registration recovers the import GST on inventory (non-resident importer setup with a customs broker, landed-cost pricing on its own site); BC's PST analysis runs independently and registers the seller under BC's non-resident rules for its direct sales; Quebec's QST registration follows its own threshold the next year. Eighteen months in, both companies' Canadian margins carry correct tax lines, recovered import GST, and zero retroactive exposure — against the competitor case their broker described: two years of FBA sales, no registrations, and an assessment for uncollected tax that turned Canadian revenue into a write-down. The doors were the same for everyone; the difference was reading them before walking through.

Official sources

"A simplified GST/HST registration, reporting and remittance regime is applicable to these non-resident vendors." Registration is generally required where applicable revenues "exceed $30,000 CAD over any 12-month period," and under the simplified regime "there would be no entitlement to claim input tax credits." — Canada Revenue Agency, GST/HST for digital economy businesses, https://www.canada.ca/en/revenue-agency/services/tax/businesses/topics/gst-hst-businesses/digital-economy.html

"Some supplies are zero-rated under the GST/HST – that is, the GST/HST applies at a rate of 0%. This means that you do not charge GST/HST on these supplies, but you may be eligible to claim ITCs for the GST/HST paid or payable on property and services acquired to provide these supplies." Exports of goods and services are zero-rated. — Canada Revenue Agency, RC4022 General Information for GST/HST Registrants, https://www.canada.ca/en/revenue-agency/services/forms-publications/publications/rc4022/general-information-gst-hst-registrants.html

Practitioner note

Canada's non-resident sales tax rules are deliberately easy to trip and genuinely manageable once mapped: three registration doors, a border layer, and four provincial add-ons, each with thresholds that reward the quarterly sweep. Our US-seller builds run threshold-registration-mechanics-calendar in that order, and the economics argue themselves — registration costs weeks, while uncollected tax costs margin, retroactively, with interest.

See also: For whether you charge GST/HST to US clients, see whether you charge GST/HST to US clients; and browse every cross-border tax topic guide, organized by situation.

Next step

Fairlight prepares the Canadian market-entry tax build — regime and province registration mapping, tax-engine and B2B validation setup, importer-of-record and customs structuring, and the quarterly threshold sweep that keeps the map current. See cross-border pricing or book a call.