A defensible storage invoice is one the customer can reproduce from their own data. Everything else is an argument waiting to happen.
Key takeaways
Structure the invoice in three layers and price each separately: storage (space occupied over time), handling (touches: receipt, putaway, pick, pack, load), and accessorials (everything else, each named in the agreement before it can appear on a bill). Then make sure every line is derived from a fact the customer can verify from their own purchase orders and shipment records.
That is the whole discipline. The tax and record-keeping mechanics below are the part that turns a defensible structure into a defensible file.
Storage rates fail commercially when the customer cannot reproduce the number. Pallet positions occupied on a stated measurement date, or a period average taken on a stated cadence, both work because the customer’s own receipts and shipments predict them. A rate expressed against a figure only your system can produce — occupied cube derived from an internal capacity model, for example — will be queried every month.
Where a system can help is in making the measurement objective rather than negotiable. A warehouse management system enforces location stocking limits, which help guarantee that work isn’t created to request inventory to be put in a location that doesn’t have the physical capacity to carry the inventory, and reports occupancy against locations that were defined in advance rather than estimated afterwards.
Name the measurement, the cadence and the rounding
Three sentences in the agreement prevent most storage disputes: what is measured (occupied pallet positions), when it is measured (daily average, or on the 1st and 16th), and how a part period is treated. Ambiguity here is not resolved in the 3PL’s favour by default.
Bundling handling into a storage rate is how 3PLs end up subsidising their busiest customers with their quietest ones. Separating them also gives you a defensible basis for a rate change: if a customer’s order profile shifts from full pallets to eaches, the handling line moves and the storage line does not, and the conversation is about facts rather than about whether you are putting prices up.
Handling units should mirror the work the system actually creates. Warehouse work is defined so that each work template must include at least one Pick operation and one Put operation to drive the basic work operation of transferring on-hand inventory from one location to another — so receipt, putaway, pick and load are natural billing events because they are already discrete transactions.
The rule is simple and unforgiving. If a charge is not in the schedule, it does not go on the invoice this month; it goes into next year’s schedule. Detention, after-hours receiving, pallet exchange, rework, relabelling, disposal, special counts and reporting are all legitimate charges, and all indefensible as surprises.
Some accessorials are genuinely regulatory rather than commercial. In a customs bonded warehouse, damage requires an approved Form K11, Certificate of Damaged Goods, and short-shipment evidence carries a deadline — where evidence of a short-shipment is not presented within 60 days of the date of warehousing, an ex-warehouse accounting entry must be presented to account for duties on the quantity short-shipped. The work of producing those documents is real, and it should be priced, not absorbed.
Two points matter more than any other. First, the tax on a storage and handling supply is not yours to trade away: every person who makes a taxable supply shall, as agent of His Majesty in right of Canada, collect the tax under Division II payable by the recipient in respect of the supply. Discounting the tax line is not a commercial gesture, it is a shortfall you fund.
Second, registration is not optional above the threshold. every person who makes a taxable supply in Canada in the course of a commercial activity engaged in by the person in Canada is required to be registered, except where the person is a small supplier, and the small supplier test turns on total consideration for taxable supplies in the preceding four calendar quarters not exceeding $30,000, or $50,000 where the person is a public service body.
A specific point for 3PLs handling imported freight: goods sitting in a customs bonded warehouse have not been released, and the programme provides for the complete deferral of customs duties, anti-dumping and countervailing duties, excise duties and taxes including the Goods and Services Tax and the Harmonized Sales Tax on imported goods, up to the point the goods are released for Canadian domestic consumption or are exported. That deferral belongs to the importer, not to your storage fee — your service is still a taxable supply. Treadstone’s sister law firm sets out the importer’s side in its note on whether HST applies when a business imports goods into Ontario.
The invoice is only as good as what sits behind it. Every person carrying on a business must keep all records that are necessary to enable the determination of the person’s liabilities and obligations under this Part or the amount of any rebate or refund to which the person is entitled, and the location and language are prescribed: unless otherwise authorized by the Minister, a record shall be kept in Canada in English or in French. Income tax records run on their own clock — records and books of account must be kept until the expiration of six years from the end of the last taxation year to which they relate.
Two things are worth settling before it happens rather than after. First, timing: the basic limitation period for a contract claim in Ontario is covered in Treadstone’s sister firm’s note on how long you have to sue for breach of contract in Ontario, and the practical route is set out in its guide to suing a customer for an unpaid invoice in Ontario.
Second, and more important for a warehouse: the goods on your rack may not be unencumbered. A lender can hold security over a customer’s revolving stock — the sister firm addresses whether a corporation can grant security over inventory that changes constantly, like stock in a warehouse. Assuming you can simply hold or sell a defaulting customer’s inventory is the fastest way to turn a receivable problem into a litigation problem, and it is a question to put to a lawyer before, not after.
An Alberta 3PL bills a consumer-goods customer on three lines. Storage: occupied pallet positions, averaged across daily snapshots, at a stated rate per position per month. Handling: per receipt line, per putaway, per pick line and per outbound load, taken straight from the work transactions the system already records. Accessorials: a named schedule of nine charges, none of which can be invoiced unless it is on the list.
The customer queries a month where storage rose 14 percent. The 3PL sends the daily position snapshots; the customer’s own receipts show two containers landed early. The query closes in an afternoon, because the billing unit was one the customer could reproduce. The GST/HST on all three lines is remitted without discussion, because the 3PL collected it as agent of His Majesty in right of Canada.
Billing a 3PL is a reconciliation problem with a monthly deadline. Assembling the month’s storage and handling lines from transaction data and flagging the ones that fall outside the customer’s normal range before the invoice goes out. Checking each accessorial charge against the named schedule and removing the ones that are not on it. Drafting the explanation that accompanies a variance, with the underlying snapshots attached. Reading a customer’s remittance advice and matching part-payments to invoice lines so the aged receivable is accurate.
What it does not do is decide. Whether to waive a charge, whether to extend credit, whether to place a customer on hold, and how a supply is characterised for tax are decisions a person makes and signs.
Whichever the customer can independently verify. Positions are usually easier to reproduce; cubic pricing is defensible when the location model is explicit, since locations can be specified on any level — for example, site, warehouse, aisle, rack, shelf, and bin position.
Your storage service and the customs status of the goods are different questions. The bonded warehouse programme defers duties and taxes up to the point the goods are released for Canadian domestic consumption or are exported — that concerns the goods, not your fee for looking after them. Confirm the treatment of your own supply with your accountant.
Long enough for both regimes: GST/HST records must be kept in Canada in English or in French unless otherwise authorized by the Minister, and income tax records until the expiration of six years from the end of the last taxation year to which the records relate.
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