Tax compliance is rarely the exciting part of running an online store, but VAT and import duty mistakes are among the most expensive and time-consuming problems a growing e-commerce business can create for itself.
VAT registration thresholds and voluntary registration
You must register for VAT once your UK taxable turnover exceeds the current registration threshold (£90,000 in any rolling 12-month period at time of writing — always confirm the current figure on GOV.UK, as it is reviewed periodically) within 30 days of exceeding it. Many growing stores choose to register voluntarily before hitting the threshold, particularly if a significant share of costs (stock, packaging, software, ad spend) carry VAT you'd like to reclaim, or if trading predominantly with VAT-registered B2B customers who can reclaim the VAT you charge them anyway.
Once registered, you must charge output VAT on sales (usually 20%, though some goods are reduced-rate at 5% or zero-rated), file returns via Making Tax Digital-compliant software (most accounting platforms like Xero and QuickBooks support this natively), and can reclaim input VAT paid on business purchases.
Import duty and customs when sourcing internationally
Importing stock from outside the UK (commonly from China, the US or elsewhere) typically incurs import VAT (usually 20%, charged on the goods value plus shipping and any duty) and customs duty (a variable percentage depending on the product's commodity code, typically 0–12% for most consumer goods categories, though some categories are higher). Your freight forwarder or courier usually handles the customs declaration and collects the duty/VAT on your behalf before releasing goods, adding an admin fee for the service.
Correctly classifying your product under the right commodity code matters — misclassification (even unintentional) can result in the wrong duty rate being applied, and persistent errors can attract HMRC scrutiny. If you import regularly, it's worth either learning to classify your specific product categories accurately or using a customs broker who specialises in it.
Selling into the EU post-Brexit
Selling to EU customers now involves the same import/export dynamics as any other international market — UK exports to the EU are zero-rated for UK VAT, but the goods will incur import VAT and potentially duty when they arrive in the destination country, which is either paid by the customer on delivery (creating a poor, surprise-fee customer experience) or pre-paid by you at checkout via schemes like the EU's Import One-Stop Shop (IOSS) for consignments under €150, which significantly smooths the customer experience.
Many UK retailers selling meaningfully into the EU register for IOSS (via an EU-established intermediary, since the scheme requires an EU presence for non-EU businesses) specifically to avoid the friction and abandoned-parcel risk of customers being hit with unexpected import charges at their door.
Selling via online marketplaces
If you sell through Amazon, eBay or Etsy, be aware that some of these marketplaces are legally required to collect and remit VAT on your behalf for certain transactions (particularly where the marketplace is deemed the 'supplier' for VAT purposes under UK marketplace VAT rules) — this doesn't remove your own VAT registration and reporting obligations for sales made directly through your own website, and getting the interaction between marketplace-collected VAT and your own returns wrong is a common source of errors worth getting an accountant's input on.
Working with an accountant who understands e-commerce
General practice accountants without e-commerce experience frequently miss category-specific issues — multi-channel VAT treatment, import duty reclaim opportunities, or inventory valuation methods that materially affect your reported profit and tax liability. It's worth specifically seeking an accountant or bookkeeper with existing UK e-commerce clients, since the sector has enough specific quirks (marketplace VAT rules, multi-currency reconciliation, inventory-in-transit accounting) that generalist advice can miss costly details.
Where This Fits Into Your Wider Strategy
Getting understanding UK VAT, import duties and e-Commerce tax obligations right is rarely a one-off task — it tends to need revisiting as the rest of the business changes around it. We cover this in more detail in R&D Tax Credits for UK E-Commerce Businesses: An Underused Source of Funding for Tech Investment, which is worth reading alongside this piece.
Timing matters as much as the decision itself. Many of the choices within Funding & Finance are far cheaper to get right in the first few months than to unwind later, once suppliers, customers, contracts or search engine rankings have already formed around your original setup. Where possible, build in a short review point — 90 days is a reasonable default — to check the assumptions you made are still holding before you commit further capital.
None of this happens in isolation. The decisions covered under Funding & Finance tend to interact with almost every other part of a new UK online business — your cash position, your legal structure, and the platform you eventually choose all shift depending on the path you take here. Founders who treat this as a one-off box to tick, rather than a decision to revisit as the business grows, usually end up re-doing the work six or twelve months later at a higher cost in time and money.
For related reading: Our companion guide, Understanding Earn-Outs and Deal Structures in an E-Commerce Sale, goes into this in more depth. This connects directly with Understanding Product Liability Insurance for UK E-Commerce Sellers, which walks through the practical detail. For a closer look at this, see our guide to Exit Planning and Valuing an E-Commerce Business: Preparing for a Future Sale, Even If It's Years Away.