E-Commerce Tax Guide 2026: What Online Sellers Need to Know About VAT and MTD

By Richard

Selling online has never been more accessible, but for many UK small business owners, the "back-office" side of things: specifically taxes: can feel like a maze. As we move through 2026, the landscape for e-commerce taxation in the UK has become more digital and more integrated than ever before.

Whether you are a side-hustler growing your Etsy shop or an established Amazon FBA seller, staying compliant isn't just about avoiding penalties; it’s about having a clear picture of your business's health. In this guide, we’ll break down everything you need to know about VAT, the new Making Tax Digital (MTD) rules, and how to manage your records across different marketplaces without losing your mind.

1. The VAT Threshold: The £90,000 Question

The first thing every online seller needs to track is their turnover. In 2026, the VAT registration threshold remains a key milestone for growing businesses.

When do you need to register?

If your taxable turnover exceeds £90,000 in any rolling 12-month period, you must register for VAT with HMRC. It is important to remember this is a rolling period, not a fixed calendar year. If you look back at the last 12 months today and find you’ve hit that limit, you have 30 days to notify HMRC.

Voluntary Registration

Even if you haven't hit the £90,000 mark, many e-commerce sellers choose to register voluntarily. Why? Because it allows you to reclaim the VAT you pay on your business costs, such as stock, packaging, and even your Amazon or eBay seller fees. If you sell zero-rated goods or have high startup costs, voluntary registration might actually save you money. It is also worth understanding the different VAT schemes for small business before you register.

2. Selling on Marketplaces: Amazon, eBay, and Etsy

Managing taxes when you sell on multiple platforms can get complicated quickly. Each marketplace has its own way of reporting sales and deducting fees.

Record-Keeping for Marketplaces

When you sell on platforms like Amazon, eBay, or Etsy, the "payout" you receive in your bank account is not your turnover. Your turnover is the total amount the customer paid before the marketplace took its cut.

To stay compliant with HMRC, you must keep records of:

• Gross Sales: The total amount paid by the customer.

• Marketplace Fees: Commission, listing fees, and advertising costs.

• Shipping Costs: What you charged the customer versus what you actually paid.

Using cloud accounting software that integrates directly with these platforms is the best way to ensure your data is accurate. Many sellers find that a specialist accountant can help set up these digital links so that sales data flows automatically into their tax returns.

3. Cross-Border Sales: The £135 Rule and Beyond

If you ship products to customers outside of the UK, the tax rules change. This is often where sellers get caught out.

The £135 Consignment Rule

For goods imported into the UK and sold to consumers, the £135 rule is vital.

• Orders ≤ £135: For most marketplace sales, the platform (like Amazon or eBay) is responsible for collecting and accounting for the VAT at the point of sale.

• Orders > £135: Import VAT and customs duties are usually charged at the border. You need to decide if your customer pays these on delivery or if you will handle them via a "Delivered Duty Paid" (DDP) service.

Selling to the EU

Since the UK left the EU, selling to European customers requires extra steps. Many UK sellers now use the Import One-Stop Shop (IOSS) or similar schemes to simplify VAT collection for EU sales. Without the right setup, your European customers might be hit with unexpected tax bills and handling fees when their package arrives, leading to bad reviews and returned items.

4. Making Tax Digital (MTD): The 2026 Update

2026 is a massive year for the UK tax system. Making Tax Digital (MTD) is no longer just for VAT; it is expanding to cover Income Tax as well.

MTD for VAT

If you are VAT-registered, you must already be using MTD-compatible software to keep digital records and file your returns. There is no "soft landing" anymore: HMRC expects digital links between your marketplace reports and your tax filing software.

MTD for Income Tax (ITSA)

Starting in April 2026, sole traders with a qualifying income over £50,000 must transition to MTD for Income Tax Self Assessment (ITSA). This is a huge shift. Instead of one annual tax return, you will be required to:

1. Keep digital records of all income and expenses.

2. Send quarterly updates to HMRC via software.

3. Submit a final declaration at the end of the tax year.

This makes hiring an online business accountant more important than ever. The workload for manual bookkeeping is effectively quadrupling, and the margin for error is shrinking.

5. Digital Record-Keeping Best Practices

To survive an HMRC audit and make your life easier, you need a solid digital trail. With more digital reporting on the horizon, including changes around e-invoicing and data sharing, it helps to keep an eye on what is coming next. Our guide to E-Invoicing is Coming to the UK: What Peppol Means explains why these future changes matter for SMEs.

Here are the "Golden Rules" for e-commerce record-keeping in 2026:

• No Manual Entry: Use software that "talks" to your bank and your marketplaces. Manual spreadsheets are increasingly seen as a risk under MTD rules.

• Six-Year Rule: You must keep your digital records for at least six years. Cloud storage makes this easy, but ensure you have backups.

• Separate Bank Accounts: Never mix your personal spending with your business sales. It makes bookkeeping a nightmare and can raise red flags with tax authorities.

• Capture Receipts on the Go: Use apps to snap photos of your postage receipts or packing supply invoices immediately.

6. When Do You Need an Accountant?

Many sellers start out doing their own taxes, but there comes a point where the complexity outweighs the cost savings of "DIY."

You should consider looking for a specialist e-commerce accountant if:

• You sell in multiple currencies: Managing exchange rates and foreign VAT is a specialist skill.

• You use multiple marketplaces: Reconciling Amazon, eBay, and a Shopify store manually is a recipe for disaster.

• You are approaching the £90k threshold: An accountant can help you plan the transition so you don't lose 20% of your profit overnight.

• You are confused by MTD: With the 2026 changes to Income Tax, having an expert ensures you don't miss a quarterly deadline.

At Accountant Search, we specialize in matching SME owners with accountants who actually understand e-commerce. You don't just need someone to "do the books"; you need someone who knows how to compare accountant services and find the right fit for your specific niche.

Conclusion

The world of online selling in 2026 is fast-paced and digital-first. While the tax rules might seem daunting, they are manageable with the right tools and advice. By staying on top of your VAT thresholds, embracing MTD software, and knowing when to ask for professional help, you can focus on what you do best: finding great products and serving your customers.

If you’re feeling overwhelmed by the upcoming MTD for Income Tax changes or need help navigating cross-border VAT, we can help. You can also read Accounting Services UK: The Complete Guide if you want a broader overview before you choose support. Find a specialist e-commerce accountant today and take the stress out of your 2026 tax return.