How to check manual and one-off charges on a 3PL invoice

Why manual and one-off lines need their own check#

Rate and activity checks test lines built from counts of orders, receipts and storage (Activity verification: did the billed activity actually happen?). Manual and one-off lines have no count behind them, so they need their own evidence. Some warehouse work can't be priced until it exists, and in some billing systems these charges are added separately from activity billing, with only an optional comment or description to explain them^2,3. Two guides written for 3PLs name manual data entry⁷ and undocumented special projects⁶ among causes of billing errors and discrepancies.

Among Implentio customers' 3PL contracts, roughly 40% include hourly project labor and about a quarter show lump-sum project lines.

What counts as a manual or one-off line#

A line counts as manual or one-off whether someone keys it in or it carries over from a work order. "Manual" describes how the line reaches the invoice. It isn't a fee for work done by hand, such as one 3PL's fee for creating an order for you⁵; those per-event fees are checked like other activity (Manual order entry and customer-service-originated orders).

"Labor" here means warehouse work billed by the hour, not pick-and-pack labor priced per order, and "adjustment" means the 3PL's correction of its own charge, not a carrier's post-ship adjustment (Carrier weight and dimension adjustments: how to dispute them).

A carrier or broker sets the cost of third-party freight, which can reach you directly, pass through at cost or marked up, or be priced on the 3PL's own card. A retailer deducts a chargeback from your payment, and it can also reach a 3PL invoice as a charge or a credit. A monthly minimum shortfall can also be a separate line with no detail rows, added by hand in at least one billing system¹⁴; see Verifying minimum-billing calculations.

How to find them on your invoice#

Signs that a line is manual or one-off:

• A line with no rows in the detail file.
• An amount with no quantity or unit.
• A line name that wasn't on last month's invoice.
• A negative amount.
• A work date or period outside the billing period.
• A separate invoice: one 3PL's invoice guide describes assembly projects both on and off the main invoice⁵ (see Separate invoices for fulfillment, storage, shipping and freight: tying them together).

Inventory, receiving and returns work can also sit under special projects or general labor.

Check the lines you can't afford to get wrong in full, such as large, new, manual or changed-rate lines, and keep them out of any sample¹³. A sample of the rest of the invoice says nothing about them (How often to audit: every invoice, sampling or quarterly?).

How to check each line, step by step#

A work order, hours log or credit line is the 3PL's record: it shows what was billed, not that you asked for the work or agreed the amount. Pair each with a record you hold, such as your request or approval, the goods you got back or your dispute log.

1. Find the basis. Look for the rate card line, signed quote, statement of work (SOW), amendment or written approval that prices the work. If there's none, ask for it, and if none comes, dispute the line in writing inside the window (Short-paying vs. paying in full and disputing).

2. Check the approval against the contract's rule. If the contract sets a threshold in hours or dollars per job, check each job against your own approval records. If the contract sets an hourly rate and no approval rule, the 3PL can bill hourly work at that rate without your sign-off. Where a contract adopts them, the IWLA standard terms (revised January 2026) charge for labor "required for services other than ordinary handling and storage"¹. Either way, ask for the request record and agree an approval rule.

3. Check the quantity. On per-worker billing, two people working one hour are two billed hours; on elapsed-time billing, they're one. Check headcount, role, the minimum increment and any per-job minimum on the 3PL's log, and compare work dates with your own requests. Count units against goods you can see, such as kits. A lump sum can't be checked without its quote or work order. With no hours log, ask for the date, task, headcount and hours of each job.

4. Check the rate. Where the card prices roles separately, match each hourly rate to the role that did the work. Check what triggers overtime, billed as a separate rate or an hourly premium (After-hours, weekend and holiday labor premiums), and use the rate in effect when the work was done (Rate verification: checking every billed rate against your rate card).

5. Recalculate the line. For hourly and per-unit work:

   Expected = quantity × rate, after rounding hours to the contract's increment

   For materials rebilled at the supplier's cost or cost plus a stated markup:

   Expected = supplier cost × (1 + stated markup)

   Materials priced per box on the 3PL's card use the card rate; for a monthly supplies bill, ask what it covers. Where materials are rebilled at cost or cost plus, the 3PL should share its cost, so ask for the supplier's invoice behind each rebill.

6. Check the period and look for repeats. Work can be billed on a later invoice than the month it was done; in one warehouse billing system, a work-order charge reaches the next invoice after the work order closes³. Search earlier invoices for the same work order, SKU list, integration or purchase. A repeat can be legitimate: a second batch of new SKUs, a second integration, a project billed by milestone¹⁰, pilot work that was free for a set period and is billed once it ends⁴, or a fee the contract says recurs. In the invoices we review, a recurring fee is sometimes named like a one-time fee, such as an integration fee billed every month.

7. Tie adjustments and credits to their source. Each should name the invoice and line, or the dispute, it corrects⁹, carry the right sign and match the amount agreed in writing, or the contract's terms for a service-level credit or claim. In a month under the minimum, a credit for an earlier month on fees that count toward it raises the shortfall by the same amount if it's applied before the shortfall is calculated. Unless the contract sets the order, ask for such credits to be applied after. If a credit names no source, match it to your dispute log by amount and date, and keep that dispute open until the 3PL confirms.

8. Log the result. Record each line as an overcharge, an undercharge, a legitimate item or a question, with its evidence (Dispute and credit tracker). Some billed activity never appears in your order data: an insert your team asked to add to every order for a promotion, a free case, or a replacement order keyed by customer service. Keep a written list of standing instructions with their start and end dates, and check whether your order fee already includes routine inserts. For one-off additions, ask your 3PL to show the order reference and who asked. Until you find the request, log the line as a question, not an overcharge. See Building an audit trail your finance team can rely on and Not every variance is an overcharge: undercharges, manual items and special projects.

What good looks like#

On a well-run account, every manual line traces to a document you can look up:

• Each line carries a reference: a work order, quote, SKU list, supplier invoice, or the original invoice line.
• Hours logs show the date, headcount, role and time for each job.
• One-off work starts from a written request with an estimate.
• Each credit or adjustment names what it settles.
• Project work is billed in the period it's done or on the quote's milestones, and shows its work date if billed late.

One guide written for 3PLs suggests logging ad hoc work "with start/stop times, SKU counts, and photo evidence if needed"⁴.