Ask three distributors for a per-watt price on the same 400W module and you will get three different numbers - not because one is lying, but because the number depends on quantity, freight, payment terms and which vintage of that module is in stock. This is what actually moves the price a contractor pays.
The quoted price is per module, not per watt
Manufacturers publish a price per module. The per-watt figure is arithmetic: price divided by wattage. That is why a 40W difference between two modules of the same family changes the per-watt cost more than most people expect, and why comparing "per watt" across brands with different wattages hides how much of the difference is freight and handling.
What really moves the number
- Quantity tier. Pallet pricing is not the same as container pricing. Every distributor has at least two tiers and often three - unit, pallet, container. Ask which tier the quoted number is in.
- Freight. Modules are bulky, fragile at the frame edge, and freight class matters. A pallet shipped LTL with a liftgate can add more per-watt than a brand difference. Freight quoted against a ZIP, not a state, is the only real number.
- Availability and vintage. A module that is in stock at a warehouse ships this week; one that is a container on the water is priced differently and carries schedule risk. The cheap quote is often the one that arrives a month late.
- Payment terms. Net terms and card pricing change the effective cost. A 3% card fee on a pallet order is not rounding error.
Where the hidden cost sits
Most projects that go over budget on modules do so on the accessories: rail, clamps, flashings and wire that were not in the panel quote, plus the second freight charge to get them. A complete BOM quoted together is consistently cheaper than piecemeal ordering, even when the per-panel number looks higher.
How we quote it
Send the array size, module class and delivery ZIP to the quote desk and you get line-item trade pricing with freight, current availability and lead time in one reply. To see the classes we stock, start with the 400W panel guide, the 450-550W guide or the 550W-700W guide, or browse all solar panels.
