March 2026 UK Tax Digest for Ecommerce Businesses
Welcome to your March 2026 UK tax digest. If you are running an ecommerce business as a UK Limited Company, you already know that the landscape changes faster than a viral TikTok trend. Staying compliant isn’t just about ticking boxes; it is about protecting your cash flow and keeping your brand clean in the eyes of HMRC. For official guidance and the most up-to-date tax updates, refer directly to HM Revenue & Customs (HMRC) on GOV.UK.
This month, HMRC has pushed out updated mileage reimbursement rates (big deal if you’re paying staff/directors for business travel), and we’ve now had the Spring Statement (3 March 2026). Alongside that, HMRC’s March 2026 Employer Bulletin flags a few payroll and compliance items you should not ignore—even if your main focus is VAT and ecommerce operations.
Key items to action now (March–Apr 2026):
- Personal Allowance Increase: HMRC has officially announced the first rise in years! From 6 April 2026, the tax-free personal allowance increases to £13,570 (up from £12,570).
- Child Benefit Rule Change (LIVE TODAY): As of 14 March 2026, the UK has officially moved to a household income assessment for Child Benefit. Thresholds are higher and the taper zone is wider—good news for most middle-income families.
- Uncertain Tax Treatment (UTT) Consultation: HMRC launched a consultation on 13 March 2026 to expand UTT reporting to include Stamp Duty Land Tax, National Insurance, Inheritance Tax, and CGT for high-value uncertainties.
- VOA + HMRC Integration: The Valuation Office Agency (VOA) will be integrated into HMRC starting 1 April 2026. Core functions won’t change, but your contact channels might shift to digital-first.
- Prioritise P11D/benefits reporting for the tax year ending 5 April 2026 (late/incorrect submissions can trigger penalties and messy corrections).
- Prepare for Making Tax Digital (MTD) for Income Tax starting 6 April 2026 if your self-employment and/or property income is over £50,000 (you’ll need digital records and quarterly updates via compatible software).
- Prepare payroll for the new Student Loan “Plan type 5” coming in the 2026–2027 tax year.
- Register for the new Vaping Products Duty from 1 April 2026 if you manufacture, import, or deal in vaping products.
- Expect Winter Fuel Payments recovery to start from April 2026 (via PAYE tax codes) for individuals earning over £35,000.
- AEOI/CRS registration for trusts was mandatory from 31 December 2025 and HMRC checks are ongoing.
- Update mileage reimbursement settings: HMRC has updated Advisory Fuel Rates (AFR) and Advisory Electric Rates (AER) effective 1 March 2026. This matters if you reimburse business mileage in a company car (or if you’re repaying private fuel back to the company).
- Spring Statement outcomes (3 March 2026): Key confirmations include a 2% dividend tax rate rise (Basic: 10.75%, Higher: 35.75%), NIC cuts for the self-employed (Class 4 to 8%, Class 2 abolished), the National Living Wage rising to £12.71, and an Inheritance Tax relief cap on the first £2.5m (£5m for couples). There were no brand-new headline tax rises announced, but fiscal drag (frozen thresholds pulling more income into higher bands) remains a real cost factor.
Whether you are selling via Shopify, Amazon, or your own bespoke platform, these updates directly impact your day-to-day operations. Let’s dive into what you need to know right now to keep your UK limited company accounting on the right track.
March 12 Update: HMRC Crypto Tax Alert
HMRC has issued a fresh alert for 2026 regarding cryptocurrency. If your ecommerce business accepts crypto or you hold digital assets personally, remember that profits over £3,000 in a tax year may trigger Capital Gains Tax (CGT). HMRC is increasing its data-matching capabilities, so ensure every transaction is logged and reported correctly to avoid penalties.
New HMRC Security Measures: The ‘0990’ Requirement
HMRC has stepped up its game to fight fraud. As of late January 2026, there is a new hurdle for anyone registering for VAT. If you are a new seller or moving your business structure, you must take note of the VAT registration application reference number.
This number, which always starts with ‘0990’, is now a mandatory requirement when you enroll for VAT services on your online business tax account. Why the change? Fraudsters were previously intercepting legitimate VAT numbers and opening accounts before the actual business owners could. This caused massive headaches and delays in getting VAT returns filed.
By requiring the ‘0990’ reference, HMRC ensures that only you—the rightful owner—can access your online services.
Pro Tip: Keep this number safe. If you lose it, the recovery process can be tedious. If we are handling your VAT return services, make sure to forward this reference to us immediately so we can get your digital dashboard synced without delay.
2026 Security Update: Mandatory MFA
HMRC is tightening access controls across online tax accounts. As of March 2026, you must have a backup multi-factor authentication (MFA) option set up (for example, an authenticator app or a passcode-style backup method) to reduce fraud risk and prevent account lockouts.
Do this now to avoid losing access at the worst possible time (VAT deadlines, payroll runs, or year-end filing):
- Add a backup MFA method to your HMRC/Government Gateway sign-in settings so you’re not dependent on one phone number or one device.
- Store recovery details securely (and keep them accessible to the person responsible for compliance in your business). This speeds up recovery if a device is lost.
- Test sign-in access quarterly to catch issues early. This prevents last-minute delays when you need to file or approve submissions.
March 2026 Employer Bulletin: Payroll & compliance items you should action now
Even if you’re ecommerce-first, payroll and reporting slips can create HMRC noise fast. Here are the March 2026 items worth putting straight onto your internal checklist.
1) Put expenses & benefits reporting (P11D) at the top of your March/April list
HMRC has made it clear that reporting expenses and benefits for the tax year ending 5 April 2026 is a priority.
Do this to avoid late filing penalties and rework:
- Reconcile benefits and reimbursed expenses early (don’t leave it until after year-end).
- Confirm what you are payrolling vs reporting on P11D so you don’t duplicate or mis-report.
