How Supply House Pricing Works, From List to Invoice

Supply house pricing works by starting from a published list price and subtracting your way down through a stack of rules until one of them produces the number that prints on your invoice. Manufacturer list sits at the top. A category multiplier or column discount comes off that. A negotiated contract rate can override it. A special pricing agreement between the manufacturer and the distributor can push it lower still on named part numbers. And when none of those rules can be matched to the transaction in front of it, the system falls back to the counter price.

That is the whole machine. Nobody hands you a diagram of it, because from the distributor’s side it is not one system, it is six modules in an ERP that were bought at different times.

This post walks the stack top to bottom, names each number in the vocabulary your rep actually uses, and shows you how to work backward from an invoice line to figure out which rule fired. If you already know the stack and want the fine detail, contract price versus counter price covers the fall-through problem and column pricing covers tiers.

The six numbers in the stack

Every price you are ever quoted is one of these, or a modification of one.

List price. The manufacturer’s published, undiscounted price. In the electrical trades this same number is called trade price, column 3 price, or end column price depending on who is talking. Vision InfoSoft, which publishes pricing data for electrical contractors, defines trade price as the non-discounted wholesale price published by the manufacturer and notes those aliases explicitly. Nearly nobody pays list. It exists so that every discount downstream has something to hang off.

Column or multiplier price. A percentage off list, or a decimal factor applied to list, set per product category. A distributor ERP built for electrical holds category-specific percentage discounts off list as the actual structure of a contractor agreement, with separate rates on lighting, on wire and cable, and on breakers and panels.

Net price. The number after the multiplier is applied. When a rep says “your net is thirty-eight fifty,” that is list times your factor, already computed. It is not a separate pricing scheme, it is the output of one.

Contract price. Your specific negotiated rate, loaded against your account number. Epicor’s electrical distribution platform lists contract pricing as a discrete module holding customer-specific rates, separate from its counter sales module. Two modules, two code paths, which is exactly why a transaction can go down the wrong one.

Job quoted price. A price good for named quantities on a named job, usually for a defined window. It is the sharpest number your supplier will ever give you and the most fragile, because it is scoped to a quote number and a quantity.

Counter or walk-in price. The default sell price when no customer rule matches. Nothing punitive about it: it is the price for a transaction that showed up without an agreement attached, which is precisely what a cash walk-in is.

Underneath all six sits a seventh number you never see: the distributor’s own cost, which is itself moving. More on that below.

Who sets which number

This is the part that changes how you negotiate, so it is worth getting straight.

Number	Set by	Can your rep change it
List price	Manufacturer	No
Column or customer class	Distributor, corporate level	Rarely, and slowly
Category multipliers	Distributor, rep and branch manager	Yes, this is the negotiation
Contract price on a SKU	Distributor	Yes
Job quoted price	Distributor, backed by the manufacturer	Yes, per job
Special pricing agreement	Manufacturer	No, they can only request one
Counter price	Distributor system default	Not per transaction

Read that table twice. Two of the seven rows are outside your rep’s control entirely, and one of them (the SPA) is often the single largest lever on what your price can be. When a rep says “that is the best I can do on that line,” they are frequently telling the truth about the manufacturer, not stonewalling you.

Where the price data physically comes from

Distributors do not key in list prices by hand. They subscribe.

Trade Service, now part of Trimble, supplies managed pricing and product data from major manufacturers in one source, with fields including manufacturer catalog number, list price, and unit of measure, syncing into distributor ERPs. Distributors then price from those sheets plus in-house sheets. Electrical Trends describes the working reality: sheets with columns showing several gross profit percentages for resale, plus blanket pricing, customer classification buckets, and velocity classes.

The same plumbing reaches your estimating software. NetPricer feeds electronic pricing into participating estimating packages, but only for products your distributor feeds to the service on your behalf. Your distributor controls what your estimating software believes a part costs. That is not a conspiracy, it is how the data licensing works, but it does mean your estimate and your invoice can disagree without anyone doing anything wrong.

The lookup order: how one line gets priced

When a counter person or an order entry screen adds a line, the system runs down a hierarchy. The exact order varies by ERP, but the shape is consistent:

Is there an open job quote covering this account, this SKU, and this quantity? Use it.
Is there a contract price loaded for this account and this SKU, in date, at this branch? Use it.
Is there a category-level discount or multiplier for this customer class? Apply it to list.
None of the above. Use the default sell price.

Your price is not attached to you as a person or to the part as an object. It is attached to a join between three records: your account, the SKU, and the branch. Break any one of those and the system does not throw an error, it quietly moves to the next rule.

That is why a substitution kills a good price. The counter is out of your exact catalog number and hands you the equivalent from another manufacturer. Steps 1 and 2 have no record for that catalog number, so you land on step 3 or step 4.

The number you never see: the distributor’s cost

Two things move underneath your price without anyone calling you.

The first is list price itself. Manufacturers reprice, and in metals-heavy categories they reprice often. The BLS producer price index for copper and brass mill shapes ran 747.384 in January 2026 and 803.275 in June 2026 (preliminary, not seasonally adjusted). AGC reported that in May 2026, copper and brass mill shapes were up 26.8% year over year while contractors’ bid prices rose only 3.5%. Your multiplier can be completely unchanged while your price climbs, because the multiplier is applied to a number that moved, and it is also part of why distributors price a job as late as they can, the pattern behind a gear quote that lands at 4:55 on bid day.

The second is the manufacturer support layer. Special pricing agreements, ship and debit, billbacks: a deal between the manufacturer and the distributor that lowers the distributor’s effective cost on named products. Enable, which builds rebate software for distribution, describes SPAs as rebates that return money up the supply chain after the sale. SparXiQ estimates that 25% to 50% or more of a distributor’s revenue may carry vendor cost supports, typically a 10% to 20% reduction against standard into-stock pricing. That layer is covered in full in what a special pricing agreement is.

Buying groups sit alongside it. Electrical Wholesaling reports that 32.2% of total electrical distribution sales flow through members of buying and marketing groups, whose rebates are, in a bad quarter, the only profit some distributors see. Affiliated Distributors alone reports over 1,000 independent distributor members and more than $100B in annual sales across electrical, HVAC, plumbing, PVF and waterworks.

None of that is visible to you. All of it sets the floor on what your rep can say yes to.

Why the same part costs two different amounts in the same month

Given the stack above, here are the ordinary, no-bad-faith reasons two invoices for one SKU disagree:

The agreement expired. Contract pricing carries effective dates and falls through silently on expiry.
A different branch handled it and does not have your agreement loaded.
It was a will-call ticket written at the counter instead of an order attached to your account. Will-call pickup is standard supply house practice, and it is a different transaction path.
Someone bought on the wrong account, or on a cash ticket.
The part number was substituted.
The job quote ran out of covered quantity.
List price went up and your multiplier stayed the same.
The unit of measure changed. Per each versus per bag of 100 looks identical to a price change until you read the UOM column.

The last one is not a pricing problem at all, and it is a top-three cause of “they raised my price” that turns out not to be. Check it first. The broader pattern is material price creep, which is what you get when several of these stack up quietly over a year.

How to trace your own price in twenty minutes

You can do this with paper you already have.

Pull three invoices for the same SKU across three different months. Same catalog number, same unit of measure.
Write down the unit price, the branch, the account number, and the document type (order versus counter or will-call ticket) for each.
Look for a contract, agreement, or quote reference printed on the line. Many distributor invoices print one when a rule was applied. A line without one, sitting next to lines with one, is a line that fell through.
If all three match on branch, account, document type and UOM, and the price still moved, your list price or your multiplier changed. That is a rep conversation.
If any of them differ, you found a lookup failure, not a price increase. That is a credit request, and a short, specific email usually settles it.
Do this monthly, not annually. Recent lines get corrected. Old ones get explanations.

What to ask your rep

Ask for the agreement in writing. Specifically: effective dates, every product category it covers, the discount or multiplier on each, and which categories are not covered. That last list is where your leaks are.

Then ask which branches have the agreement loaded, and ask them to load it at any branch you actually buy from. Ask whether your regular parts are on any manufacturer program, and whether that program survives a substitution. Ask what your quotes’ expiry and quantity terms are, and write the quote number and covered quantity on your own copy.

If you want the full version of that conversation, how to negotiate with your supply house covers running it off your own invoice history instead of off vibes.

The short version

List is the reference number. Almost nobody pays it.
Column, multiplier and net are the same idea expressed three ways: a factor off list.
Contract price is your negotiated rate keyed to your account, your SKU and your branch.
Job quotes are the sharpest and the most fragile price you will get.
Counter price is the fallback, not a penalty.
Manufacturer SPAs and buying group rebates set the floor under all of it and never appear on your invoice.
When a price moves, check UOM, branch, account and document type before you assume anyone raised anything.