In-House vs 3PL Fulfilment: The True Cost for UK Brands
01/10/2026
When you start selling online, fulfilment feels like the easy part: an order comes in, you pack a box, you ship it. The honest answer to "should I switch to a 3PL?" is that in-house fulfilment stops being free at around a few hundred orders a month, when the hours you spend packing cost more than a 3PL's per-order fee. Below is an honest breakdown of the true costs on both sides, with the maths shown, so you can judge where your own tipping point sits.
The true cost of packing it yourself
Packing one order takes roughly 5 to 10 minutes: find the product, pick it, pack it, label it, book the courier. At 500 orders a month, that is 40 to 80 hours of labour. Valued at the UK National Living Wage of £12.71 an hour (the rate from April 2026; rates change annually, see gov.uk), that is roughly £510 to £1,020 a month in time alone, before a single box or label is bought. A fulfilment centre does this work at scale: at Storage and Logistic, pick and pack starts from £0.70 per order, with label service at £0.25 per order. Our detailed breakdown of 3PL fulfilment costs in the UK shows how each fee line compares.
Storage: the silent margin killer
Renting warehouse space means a lease, business rates, insurance, racking and equipment. Most small brands pay for far more space than they need, all year, to cope with one busy quarter. A 3PL charges for the space you actually use and scales with you, with no fixed contracts and no minimum storage. That pay-as-you-go model is built for brands that grow in bursts. For the detail on formats and pricing, see our guide to warehouse storage for growing brands.
Shipping rates and the volume gap
Couriers give volume discounts. A brand shipping 200 parcels a month pays noticeably more per parcel than a fulfilment centre shipping thousands. When you outsource fulfilment, you ride on the 3PL's negotiated rates with major carriers. This is one of the least visible savings and one of the largest.
Returns: the part everyone forgets
Fashion eCommerce return rates routinely reach 25 to 40 per cent, according to Retail Gazette. Every return is a parcel to receive, inspect, re-grade, re-stock or dispose of. In-house, returns land on your doorstep and sit in a corner. A proper returns process turns them back into sellable stock fast, which matters more the higher your return rate climbs.
Worked example: the maths at 500 orders a month
This illustrative example compares your own labour against 3PL per-order fees at 500 single-item orders a month. It is not a quote. Assumptions are stated below the table.
Cost lineIn-house (illustrative)3PL (illustrative)Labour: 62.5 hours at £12.71/hourapprox. £794—Pick, pack and label: 500 x (£0.70 + £0.25)—£475
Assumptions: packing takes 5 to 10 minutes per order; the table uses the midpoint of 7.5 minutes. Time is valued at the UK National Living Wage of £12.71/hour (April 2026 rate; check current rates). Packaging materials, courier charges and storage are excluded from both sides for a like-for-like comparison. At 5 minutes per order the in-house figure is roughly £530; at 10 minutes it is roughly £1,059. Either way, in-house labour alone typically exceeds the 3PL per-order fee at this volume, before materials, space or errors enter the picture.
Ready to switch? A quick decision checklist
You are probably at the tipping point if two or more of these are true:
Packing takes up whole days each week, or bleeds into evenings and weekends.
Stock is spread across the spare room, the garage and a storage unit.
You have turned down a bulk supplier discount because you could not fit the stock.
Mispicks and late dispatches are creeping into your reviews.
Your own labour, valued honestly per hour, costs more than roughly £0.95 per order for pick, pack and label.
Growth plans (new products, new channels, peak season) would break your current setup.
If most of these sound familiar, run the numbers for your own volumes. If you are comparing providers, our fulfilment centre buyer's checklist gives you ten points to score them against. And if you are new to outsourcing entirely, start with our plain-English guide to what a 3PL actually does.
What to look for in a 3PL partner
Not all fulfilment partners are equal. Shortlist against these:
No fixed contracts: you should not be locked in to prove the model works.
Transparent pricing: per-order pick and pack rates, clear storage fees, no surprises.
Same-day dispatch: customers expect it, and late dispatch costs you reviews.
Real-time tracking: full visibility of your stock and every order.
Returns management: the full loop, not just outbound.
International capability: if you import stock, your 3PL should handle freight and customs clearance too.
The bottom line
In-house fulfilment feels free until you count the hours, the space and the missed growth. For most UK eCommerce brands, the switch to a 3PL pays for itself at around a few hundred orders a month.
Curious what your numbers look like? Try our pricing estimator and see your cost per order in seconds, or call 07380 636829 and talk to someone who packs boxes for a living.