The short answer
Landed cost is not the supplier’s unit price plus freight. It is every cost required to move the goods from the supplier’s dock to your warehouse, ready to sell or install, divided by the net weight of usable product you actually receive. For polyphosphate balls, the formula looks like this:
Landed cost per kg = (goods value + export/import freight + insurance + duty + non-recoverable taxes + port, terminal and broker charges + inland delivery + banking and FX costs + compliance and inspection costs ± quality losses) ÷ net usable kilograms
Most buyers under-estimate this figure because they stop at CIF plus duty. The gaps are usually packaging weight, non-recoverable VAT or GST, currency spread, and the cost of replacing any portion of the shipment that fails your incoming inspection. The rest of this article shows where each item comes from and how to build the number so your sales margin is based on reality.
First, confirm what you are actually importing
Before building a cost model, make sure you are costing the right material. The term “Siliphos” is widely used as a generic label, but it is a brand name, and products sold under similar descriptions are not automatically interchangeable. Polyphosphate balls, polyphosphate crystal, phosphate crystal and polyphosphate media may differ in form, dissolution behaviour, bulk density, and intended function.
It also helps to separate the functions clearly, because they influence which product you need and therefore what you pay for:
- Scale inhibition — threshold doses of polyphosphate interfere with the formation of hard carbonate scale in pipework and equipment. This is the typical role of slow-dissolving polyphosphate media.
- Water softening — removal of calcium and magnesium hardness by ion exchange. Polyphosphate media does not soften water in this sense and does not replace a softener.
- Scale removal — dissolving existing deposits. This is a different chemistry and a different product.
- Corrosion inhibition — a separate performance objective that depends on the specific formulation, dose, pH and system metallurgy.
- Filtration and disinfection — unrelated functions. A polyphosphate column does not filter solids and does not disinfect.
Being precise about the function matters commercially: if you import a scale-inhibition medium expecting softening performance, the “cheap” shipment becomes expensive once returns and complaints are counted.
Cost components you need to collect
Ask the supplier and your freight forwarder for each line item below. A missing line item does not disappear; it simply appears later as a surprise.
| Cost block | Typical source | What to confirm |
|---|---|---|
| Goods value | Supplier quotation (EXW, FOB, CIF, etc.) | Incoterm, currency, price basis (per kg, per bag, per carton) |
| Export handling & origin charges | Supplier or forwarder | Whether these are already inside the quoted Incoterm |
| Main freight | Forwarder / carrier | Chargeable weight (gross vs volumetric), LCL vs FCL, port pair |
| Marine insurance | Insurer or forwarder | Cover basis and whether it is included in the Incoterm |
| Import duty | Customs broker | HS classification and the rate applicable in your market |
| Import VAT / GST | Customs / tax authority | Whether you can recover it; if not, treat it as a real cost |
| Port, terminal, THC, documentation | Forwarder / terminal | Fixed fees vs weight-based fees |
| Customs brokerage & clearance | Broker | Entry fee, single-entry vs annual bond |
| Inland transport | Trucker | Delivery address, tail-lift requirement, unloading responsibility |
| Banking & FX | Your bank | Wire fees, payment terms, FX spread between contract and settlement |
| Compliance & testing | Lab, certifier, consultant | Any safety, potable-water-contact or labelling requirements in your market |
| Quality loss provision | Your own estimate | Allowance for non-conforming material, fines, moisture, or rework |
| Inventory carrying cost | Internal | Cash tied up in transit, storage and slow-moving stock |
Where the arithmetic usually goes wrong
Gross weight versus net weight
Freight is charged on gross weight or volumetric weight, whichever is greater. Duty and taxes are normally assessed on the customs value, not on the gross weight. But your sales price is based on net product weight. If 1,000 kg net arrives inside 1,040 kg of bags, cartons and pallets, you paid freight on 1,040 kg and can only sell 1,000 kg. Always obtain the gross weight per pallet and the number of pallets before you request a freight rate.
Volumetric weight on low-density forms
Balls, crystals and granular media do not all pack the same way. A lower bulk density means more volume for the same weight, and LCL freight is priced on volume when volumetric weight exceeds actual weight. If you switch suppliers or product form, re-quote the freight. Do not assume the old rate still applies.
Non-recoverable tax
Import VAT or GST is often recoverable if you are registered and can offset it. If you cannot recover it, or if you can only recover it after a delay, it is part of your working-capital cost and, in some situations, part of your true landed cost. Confirm this with your accountant for your specific registration status.
Currency movement between quotation and payment
A 3% move on a large shipment can be larger than the duty. If you quote your own customers in local currency while paying the supplier in US dollars or euros, add a realistic FX buffer to the model rather than hoping the rate holds.
Compliance and potable-water requirements
If the material will contact drinking water, food-grade status alone is not sufficient evidence of suitability. Potable-water suitability depends on the exact product, the application conditions, and the requirements of the destination market. Verify the documentation that applies to your case before you commit to a purchase order, and include the cost of any testing or certification in the landed cost if it is not already covered.
A worked example (illustrative figures)
The numbers below are hypothetical and are included only to show the structure of the calculation. Replace them with your own quotations.
| Line | Basis | Amount (USD) |
|---|---|---|
| Goods value (FOB) | 1,000 kg net | 1,200.00 |
| Main freight | Charged on 1,040 kg gross | 480.00 |
| Insurance | Marine cover | 25.00 |
| Duty | 5% of CIF (1,200 + 480 + 25) | 85.25 |
| Import VAT | 10%, recoverable in this example | 0.00 |
| Port, terminal, documentation | Fixed | 350.00 |
| Inland delivery | Port to warehouse | 180.00 |
| Banking and FX | Wire plus spread | 60.00 |
| Total landed cost | — | 2,380.25 |
| Cost per net kg | 2,380.25 ÷ 1,000 kg | 2.38 |
Now change one assumption: if the VAT is not recoverable, add 179.03 and the cost per net kg rises to 2.56. That single line changes your pricing decision more than most buyers expect.
Convert landed cost into the unit your customer buys
Importers rarely sell polyphosphate media by the kilogram. They sell refill bags, cartridges, or dosing devices. Two additional conversions are useful:
- Cost per filled device or cartridge. Landed cost per kg × the fill weight, plus the cost of the housing, cartridge, filter element, packaging and labour. This is the number your distribution price has to cover.
- Cost per cubic metre of water treated. This requires the dosing rate and service life for the specific application, which depend on the product and the water conditions. Ask the supplier for the technical basis rather than estimating, because a low-cost medium with a shorter effective service interval can be more expensive per cubic metre than a higher-priced one.
Incoterms: decide where your cost responsibility starts
EXW, FOB, CIF and DDP move the cost boundary. Many buyers default to CIF because it looks simple, but CIF stops at the destination port, leaving terminal handling, clearance, duty, and inland delivery with you. DDP moves more responsibility to the supplier and usually carries a higher unit price. Neither option is inherently cheaper; what matters is that your landed-cost model covers every step between the two ends. If you are new to a trade lane, request quotations under two Incoterms so you can compare the true delivered figure.
A pre-order checklist
- Exact product description, form, and intended function confirmed in writing.
- Net weight and gross weight per bag, carton, and pallet.
- Number of packages, pallet dimensions, and stackability.
- Incoterm, currency, payment terms, and quotation validity period.
- HS classification confirmed with your customs broker for your market.
- Freight quoted on the correct chargeable weight and volume.
- Duty rate, VAT/GST treatment, and recoverability confirmed.
- Any required compliance documentation identified before shipment, not after arrival.
- Inspection or sampling arrangement agreed, including who pays.
- FX buffer and financing cost included.
- Storage conditions and shelf-life expectations confirmed with the supplier for the specific grade.
FAQs
Is polyphosphate media the same as a water softener?
No. Polyphosphate media is generally used for scale inhibition at low doses. It does not remove hardness the way an ion-exchange softener does. Treat the two as separate products when you plan a system or a quotation.
Does a food-grade certificate make the product suitable for drinking water?
Not by itself. Food-grade status addresses one set of requirements. Potable-water suitability must be verified for the exact product, the application conditions, and the destination market. Ask for the specific documentation that applies to your case.
Should I use LCL or a full container?
LCL is charged on chargeable weight or volume and includes consolidation handling, so the effective rate per kg is usually higher. Once your shipment approaches a meaningful share of a container’s capacity or payload, comparing the two options is worthwhile. Run both figures through the same landed-cost model before deciding.
How often should the landed-cost model be rebuilt?
Rebuild it whenever freight rates, duty treatment, exchange rates, or the product form changes, and re-check it at least before every major purchase order. A model built a year ago is a starting point, not a current cost.
Need the figures for your own shipment?
If you tell us the application, the source-water conditions, the equipment type you are filling, the specification you need, the quantity and packaging format, and the destination port or country, we can discuss the relevant product form and the technical basis for the price. Send those details to ENVO CHEMICAL and we will help you build a landed-cost comparison you can actually use.
