Your 3PL quote looked good. Your first invoice didn't. Hidden fees are the most common cause of 3PL disappointment for eCommerce brands — and they're often buried so deep in the contract that you don't find them until it's too late. Here are the five most common ones to watch for before you sign anything.
Why your 3PL invoice is always higher than expected
You get a quote from a 3PL. It looks reasonable. You sign up, move your stock in, start fulfilling — and then the first invoice arrives and it's 30% higher than you budgeted. Sound familiar?
Hidden 3PL fees are one of the most common complaints from eCommerce brands who've switched fulfilment providers. The problem isn't always dishonesty — sometimes it's just that 3PLs quote on the most favourable assumptions and the reality of your actual operation is more complex. But the result is the same: your margins get squeezed and you can't plan properly.
Here are the five most common hidden 3PL costs to watch for — and how to make sure you're not being caught out.
Hidden fee 1: Minimum monthly charges
Many 3PLs impose a minimum monthly charge — typically £200-£500 — regardless of how many orders you actually fulfil. This is often buried in the contract and not mentioned in the initial quote.
For a brand doing 100 orders a month at £2.50 pick and pack, the pick and pack cost is £250. But if the 3PL has a £400 minimum monthly charge, you're actually paying £400 — effectively £4.00 per order, not £2.50. A 60% difference.
What to ask: "Is there a minimum monthly spend or minimum number of orders?" Before signing any contract, get this in writing. At Reilly's, there are no monthly minimums — you pay for what you use.
Hidden fee 2: Inbound handling charges
Most 3PLs charge to receive your stock — booking it in, counting it, quality checking it and putting it away. This is often called an "inbound handling fee" and can range from a flat £25-£50 per pallet to a per-unit charge of £0.10-£0.30 per item.
If you're sending in 10 pallets a month and each pallet has 200 units, a £0.15 per-unit inbound fee adds £300 a month to your costs — before a single order is fulfilled. This is almost never mentioned in headline pricing.
What to ask: "What do you charge for receiving and booking in stock?" Get a specific answer for your typical delivery volumes.
Hidden fee 3: Long-term storage charges
Many 3PLs offer competitive storage rates for the first 30-90 days — then charge significantly more for "long-term storage" after that period. This is particularly common with 3PLs who model their pricing on Amazon FBA's structure.
If you carry seasonal stock, slow-moving lines or buffer inventory, long-term storage fees can accumulate rapidly. Some 3PLs also charge for counting your stock during audits, moving it between locations or photographing damaged items.
What to ask: "Is there a different rate for stock held longer than 30/60/90 days?" Ask to see the full storage fee schedule, not just the headline per-pallet rate.
Hidden fee 4: Returns processing fees
Returns handling is often quoted as a separate line item — if it's mentioned at all. Some 3PLs charge a flat fee per return received (£1.50-£3.00), others charge per unit inspected, and some charge for restocking items back into the pick location.
For fashion or homeware brands with return rates of 15-25%, returns processing fees can add up to a meaningful monthly cost. If this wasn't factored into your initial quote, it can be a significant surprise.
What to ask: "What is your full returns processing fee — per return, per item and restocking?" Make sure this is included in any cost comparison you do.
Hidden fee 5: Account and technology fees
Some 3PLs charge a monthly "account management fee", "technology fee" or "portal access fee" on top of their per-order pricing. This covers their WMS (warehouse management system), your access to reporting dashboards and the integrations with your sales channels.
These fees range from £30-£150 a month depending on the provider — and they're charged whether you fulfil 10 orders or 10,000. For smaller brands, this can represent a significant percentage of their total 3PL cost.
What to ask: "Are there any monthly account, technology or portal fees?" At Reilly's, DespatchLab access and all platform integrations are included — there are no separate technology charges.
How to compare 3PL pricing properly
The only way to compare 3PL costs accurately is to build a full cost model based on your actual volumes. Don't compare headline pick and pack rates — they're almost meaningless without knowing the full fee structure.
Build a model that includes:
- Pick and pack per order (your actual average order complexity)
- Storage per week/month (your average stock holding)
- Carrier cost per order (for your typical parcel sizes and zones)
- Inbound handling per delivery
- Returns processing at your actual return rate
- Any monthly minimum, account or technology fees
At Reilly's, we build this model for you as part of the quoting process. Send us your volumes and we'll give you a fully itemised cost breakdown — no hidden fees, no minimum charges, no surprises on your first invoice. Call 0116 444 0444 or visit our fulfilment services page to get started.