Side Hustle Economics: Budgeting for a Physical Product Business in the UK

Selling physical products has become one of the most popular routes into self-employment in Britain. Millions of people now earn part of their income through flexible or freelance work, and a large share of them do it by sourcing goods and selling them online. The appeal is easy to see: low barriers to entry, no employer, and a product you can hold in your hand. The difficulty is that most first-time sellers budget for the visible costs — stock, listing fees, packaging — and overlook the logistics that quietly decide whether the venture makes money. Holding inventory, moving it in bulk, and getting individual orders to customers all carry costs that rarely appear in an early spreadsheet. This article sets out the three logistics costs that most often impact the margins for a UK physical-product business — storage, inbound freight, and delivery — and shows how to put realistic numbers against each before you spend anything.

Know the tax position first

Before any logistics, it is important to be clear about where you stand with HMRC. The trading allowance lets you earn up to £1,000 of gross trading income in a tax year without reporting it, a figure that has held steady for 2025/26 and 2026/27. Once gross income passes £1,000, you generally need to register for Self Assessment by 5 October following the end of that tax year. From 2027/28, the reporting threshold is expected to rise to £3,000, though the tax-free allowance itself stays at £1,000. Separately, VAT registration becomes compulsory once taxable turnover exceeds £90,000 over any rolling 12-month period. Because the allowance applies to gross income before costs, logistics expenses reduce your profit rather than your reporting obligations — so it pays to understand them early.

Measure volume, not just boxes

Stock has to live somewhere. A spare room costs nothing but fills quickly, and self-storage is the usual next step. Industry figures put the national average at around £29 per square foot per year — roughly £2.43 per square foot per month before VAT — with London closer to £44 per square foot per year.

The pricing quirk is that storage is charged by floor area, but stock stacks vertically. The number that actually matters is the total volume your inventory occupies and how it stacks, not simply its footprint on the ground. If 200 units each sit in a box of about 1.5 cubic feet, that is 300 cubic feet of goods; stacked to about 2 meters high, they need roughly 50 square feet of floor space. At the national average, that is about £120 a month before VAT, plus contents insurance. Working out the volume before you view any units stops you from paying for space the stock never uses.

Inbound freight: Density decides the bill

Buying stock wholesale or importing it almost always means pallet freight rather than parcel freight. Freight carriers price on a combination of weight and the space a consignment occupies, so the figure that really drives the quote is how dense the cargo is — its weight divided by its volume. Light, bulky goods cost more per kilogram than their weight alone would suggest. In the United States, this is formalized as an NMFC freight class, where denser cargo falls into a lower, cheaper band; UK domestic pallet networks do not use the same classification, but the underlying logic is identical.

Two points matter for a UK seller. If you import, the landed cost includes 20% import VAT and any customs duty, not just the freight quote, so build those into your per-unit figure. And because density drives the rate, knowing the weight and dimensions of a full pallet lets you check whether repacking into fewer, denser pallets would lower the bill.

Paying suppliers and taking payment

Money moving in and out of the business is a cost centre in its own right. When you pay a new or overseas supplier, and when you accept payment from customers, the method you choose carries very different protections and dispute rights. A card payment — particularly a credit card, where Section 75 of the Consumer Credit Act applies to purchases over £100 — gives stronger recourse if a supplier fails to deliver than a bank transfer, which is largely irreversible once sent. That protection is worth weighing against the processing fees a payment provider charges, since those fees come straight off your margin on every sale. Keeping business funds in a separate account also makes both bookkeeping and Self Assessment far simpler at year-end.

Last-mile delivery and transport

Getting orders to customers is the final cost, and there are two broad routes. Couriers charge per parcel, which keeps costs variable and predictable while volumes are low. Once you are making regular local deliveries, wholesale drops, or stock runs, your own vehicle can work out cheaper — and the question becomes whether to buy, finance, or lease.

Leasing a small van turns an unpredictable purchase into a fixed monthly payment that is easier to budget against sales, and it is worth working out the monthly cost of a lease from the vehicle price, term, and residual value before you speak to a dealer. If you use your own car for business mileage instead, HMRC’s simplified rate lets you claim 55p per mile for the first 10,000 business miles and 25p per mile after that, which is usually simpler than tracking actual running costs.

Building it into your price

In the end, the habit that protects margins is adding every logistics cost back onto the product itself. Take the buy price, then add inbound freight per unit, storage per unit per month, and delivery per order. Only once those are included do you know your true cost of goods, and whether your selling price leaves a profit worth the effort.

Because bulk stock ties up cash for months before it sells, a cash buffer matters too, and it is worth revisiting each cost as you grow: larger storage units are cheaper per square foot, consolidated freight lowers the per-unit rate, and delivery routes tighten up with volume. None of these costs is glamorous, but they are the difference between a side hustle that clears real money and one that quietly runs at a loss.