You can start selling online in the UK in under two weeks. Pick a platform (Shopify, WooCommerce, or a marketplace like Amazon UK), register for VAT if your turnover exceeds £90,000, set up payments, and ship your first order. The hard part is not the setup. It is getting traffic and converting it.

Most first-time UK online sellers overspend on the platform and underspend on traffic. The right balance for a £0 to £10,000 monthly revenue business: cheapest practical platform, most of the budget into customer acquisition.

Pick the platform that fits your model

Three main routes for UK sellers in 2026:

Your own store on Shopify. £25 per month for the basic plan. Owns the customer relationship. Best when you have a brand, repeat purchase, or specific products that need their own narrative. Around 60% of new UK direct-to-consumer brands start here.

Your own store on WooCommerce (WordPress). Free software, but hosting and plugins typically cost £40-£80 per month. More technical to set up. Better for content-led commerce or anything that wants tight WordPress integration.

Sell through a marketplace. Amazon UK, eBay UK, Etsy, OnBuy, or industry-specific marketplaces. The marketplace owns the customer. You get traffic on day one but pay 8-15% commission. Best for commodity products where the customer is searching for the product, not your brand.

Many UK sellers run both. Their own Shopify store builds a brand. Amazon UK provides volume. The two channels have different economics and different products.

Register the business properly

Sole trader is fine for most starting points. Register for Self Assessment by 5 October following the tax year you start. If you expect rapid growth or want liability protection, set up a limited company before you launch.

For VAT, the registration threshold is £90,000 of taxable turnover over a rolling 12 months. Below that, registration is optional. Many sellers register voluntarily once they sell internationally or have significant input VAT to reclaim.

If you sell to consumers in the EU, post-Brexit rules apply. You may need an EU VAT registration (via IOSS for low-value goods under €150, or direct registration in member states for higher values).

Set up payments

Card payments are the default. The main UK options:

• Stripe: 1.5% plus 20p for UK cards, easy integration with Shopify, WooCommerce, and most platforms.
• PayPal: 1.2%-2.9% depending on volume. Higher than Stripe but customers trust it.
• Square: similar pricing to Stripe, with stronger physical point-of-sale tools.
• GoCardless or BryxoPay: for direct debit on subscription products.
• Klarna, Clearpay, Affirm: buy now pay later. Adds 3-6% to your costs but lifts average order value 15-30% on consumer products.

For most starting online sellers, Stripe plus PayPal as a secondary option covers most of the demand.

Get the shipping right

UK customers expect:

• Free shipping above a threshold (typically £30-£50 minimum order).
• Tracked delivery on anything over £20.
• Clear delivery timeframes shown before checkout.
• Easy returns.

Carrier options for SMEs:

• Royal Mail: cheapest for small items, longest established. Tracked 48 service is the default for most non-urgent UK orders.
• Evri (formerly Hermes): cheap for moderate-weight parcels. Customer service mixed.
• DPD: more expensive but stronger tracking and customer experience.
• ParcelForce: good for heavier or international shipping.

For pricing, use a shipping calculator (Sendcloud, ShipStation, Easyship) or negotiate direct rates once you exceed 500 parcels per month.

The first-year economics

Realistic numbers for a new UK online seller selling at £30 average order value with 50% gross margin:

• Customer acquisition cost (CAC): £8-£15 in paid ads. Free channels (SEO, social organic) take 6-12 months to deliver volume.
• Order economics: £30 revenue, £15 cost of goods, £3 shipping, £1 payment fees, £8 ad cost = £3 contribution margin per order.
• Break-even monthly volume: enough orders to cover fixed costs (platform, software, your time).

Most new sellers underestimate CAC and overestimate organic growth. Plan for 12 months before paid acquisition becomes optional.

What to do before going live

Spend the time you save on platform setup on these:

• Photograph products properly. 3-5 images per product, plus lifestyle shots if relevant. Bad photos kill more sales than bad prices.
• Write product copy that answers the actual question the customer is asking. Not features. Reasons.
• Set up returns process from day one. Make it generous. UK consumer law gives buyers 14 days to return distance-purchased goods anyway.
• Build an email signup before launch. Even 100 emails from day one is more useful than 100 ad clicks.
• Plan the first three weeks of social content before launch. After launch, time disappears.

Bottom line

The setup is faster than people expect. The growth is slower. Budget for 12-18 months of paid acquisition before any meaningful organic flywheel. Plan for the gross margin to barely cover costs in year one.