Transformer Wholesale: Buying in Bulk from a China Factory

So you want to buy transformers in bulk from a Chinese factory, and you want to know what that actually involves before you commit money. Fair enough. Wholesale sounds simple from the outside, but there is a wide gap between ordering ten units to test a market and ordering a thousand units for a distribution business, and the terms, the pricing and the paperwork change as you move along that scale.

We build step down and step up transformers in Yueqing, China, and we ship wholesale orders to importers, distributors and project buyers every week. This is the version of the conversation I have on WhatsApp, written down properly, covering minimum order quantities, price tiers, mixed containers, lead times, payment and inspection.

What Wholesale Actually Means at a Factory Like Ours

The word gets used loosely online, so let me define it the way we use it internally. Wholesale means you are buying a quantity that justifies setting up a production batch for you, with your label, your packing and your carton markings, at a unit price that reflects the volume. It does not mean one unit at a discount, and it does not mean we keep a warehouse of finished stock waiting for someone to ring us.

Our minimum order is 10 pcs. That number is not arbitrary. Ten pieces is roughly the point at which a batch is worth scheduling separately, the tooling and setup cost per unit becomes reasonable, and we can hold a batch test record that means something. Below that, you are buying a sample or a small trial order, and we treat those differently.

Why the Floor Is 10 pcs and Not 1

People ask this constantly, so here is the honest answer. Winding a transformer involves setting up a machine, preparing the core and the insulation, and running a test on every finished unit. For one unit, that setup work is nearly all of the cost. For ten, it is spread over ten. For a container, it almost disappears.

Ten units also lets us do something useful for you. We can produce a small batch with consistent materials and consistent testing, so when you evaluate the product you are evaluating what a full order will actually be like. Changing material between a sample and a mass production run is a dirty trick that some suppliers play. We would rather not, and the 10 pc floor is one of the reasons we do not have to.

Tiered Pricing and How the Steps Work

Once you are above the minimum, price per unit falls as quantity rises. That is true of almost every manufactured product, but the shape of the curve surprises people. It is not a straight line. It steps.

Quantity tier	What it is normally used for	How pricing behaves
10 to 49 pcs	Market trial, a single project, a first order to test quality	Base price. This is where every new buyer starts
50 to 199 pcs	Small distributor stock, one model for one country	First real step down, setup cost is well covered
200 to 999 pcs	Regular distribution, multi-model stock holding	Material purchased in larger lots, better still
1,000 pcs and above	Container programmes, OEM brand launches	Quoted on your specification, often with a price formula

Two things worth knowing about that table. First, the biggest jump is usually between the 10 pc tier and the 50 pc tier, because that is where setup stops dominating the cost. Second, once you are past 200 pcs, the conversation changes from a price list to a specification. At that volume we are usually discussing your voltage, your plug type, your carton printing and your brand, and the price follows those decisions.

If you want the numbers for your own quantity, send us the model, the voltage and the quantity on one line of a message, and we will reply with the tier price rather than a single figure. That saves us both a round of emails.

Mixed Containers: Filling a 20GP or 40HQ

Most wholesale buyers do not order one model. You need a few hundred step down units, some bidirectional models, a batch of variable transformers for the workshop channel, and spares. That is completely normal, and it is why we quote mixed loading.

A mixed container is exactly what it sounds like. You pick the models and the quantities, we work out the carton sizes, and we produce a loading plan. The only constraint is volume and weight, not the number of different models. In practice, most buyers mix four to eight SKUs in one container.

Container	Internal volume, roughly	What it suits
20GP	About 33 cubic metres	First container, trial mix, single country launch
40GP	About 67 cubic metres	Established order where weight is not close to the limit
40HQ	About 76 cubic metres	Volume products such as small and mid range units
LCL consolidation	By cubic metre	Orders too big for air, too small for a full container

I am deliberately not printing a “units per container” figure, because it depends entirely on which model you are loading. A carton of 500VA units and a carton of 5kVA units are not the same animal, and any supplier who quotes you a flat number without asking your carton sizes is guessing. Give us the model list and we will send you a loading plan with the exact carton dimensions and packed weight for each line. Then you can check it against your own warehouse capacity before you commit.

Lead Time, Payment and Inspection

Lead Time: What 15 to 25 Days Actually Covers

Our standard lead time is 15-25 days from deposit to loaded container. Let me break that down so you know what you are buying into, because “15-25 days” means different things at different factories.

Week one is materials. Copper and core steel are ordered or pulled from stock depending on your specification and the current copper market. If you have specified a non-standard voltage or an unusual enclosure, this is where the extra days come from. Week two and into week three is winding, assembly and varnishing. Every unit is then tested individually, and the ones that fail go back for rework rather than into a carton. The last stretch is packing, labelling and loading, plus the paperwork your forwarder needs.

Two things push the timeline out. Custom nameplates and printed cartons add a few days because the printing is done outside our building. And a large order landing while the shop floor is already full of another customer’s work needs to be scheduled, so if you have a hard delivery date, tell us at the enquiry stage. If we cannot hit your date, I would rather say so on day one than explain it on day twenty-five.

Payment Terms, Inspection and Documents

For bulk orders our normal terms are a deposit with the balance against the bill of lading. For larger and repeat programmes we can talk about other arrangements, and for buyers who want that structure we are open to a letter of credit at sight through a bank both sides accept. What we are not interested in is shipping a container on a promise. Nothing personal, it is simply how a factory stays alive.

We ship FOB Ningbo or Shanghai, which suits most buyers because you keep control of the freight and you can use your own forwarder. If you do not have one yet, the brokers your country already uses will know these ports, and we can also introduce the forwarders we work with most often.

On inspection, you are welcome to arrange a third party inspection before loading. We will give the inspector access to the finished goods, the test records and the packing area, and we will not ask you to skip that step. If you would rather do it yourself, come and visit. Yueqing is about an hour from Wenzhou airport and we host buyers regularly, which is still the fastest way to judge whether a factory is real.

The export documents we prepare as standard are the commercial invoice, packing list, certificate of origin and the batch test record for your units. If your customs authority wants something additional, tell us before the order is confirmed rather than after the container closes.

Private Label, Packaging and Cartons

If you are building a brand rather than passing through generic stock, this is where the margin lives. We can print your name and model number on the unit label, put your logo on the carton, and add your own user manual in your own language. For a container-sized order, that is a normal request and we handle it every month.

What we cannot do is print a certification mark you have not earned. If the label is going to carry a standards mark for your market, you need the paperwork to support it, and we will tell you exactly which documents we can provide and which ones are your responsibility as the importer. Getting this straight before the print run saves an expensive repack.

Packaging matters more than most buyers expect on transformers, because the product is heavy and it contains a magnetic core that does not enjoy being dropped. Our cartons use foam protection and are sized for the unit, not for a generic box with air in it. If your market needs retail-ready packaging rather than plain export cartons, say so, because it changes the carton cost and the container count.

One last thing about landed cost, because this is where first-time importers get caught. Your unit price is only part of the bill. Add sea freight, your customs duty, port charges at both ends, inland trucking and the cost of holding stock. On a full container of small and mid range units, freight and duty can add a meaningful percentage to every unit, and that percentage moves with packing efficiency. A tighter carton that loads more units into the same forty foot box can beat a lower unit price from a supplier whose packaging wastes space. Ask for carton dimensions before you compare quotes, and if you want, we will run the loading plan and tell you which mix fills the container most efficiently.

The fastest quotation we ever send comes from a buyer who sends a clean list. Something like this works perfectly: model or application, input voltage, output voltage, capacity in VA, quantity, your country, and whether you want plain packing or your own brand. A photo of an existing unit you want to replace is also useful, because we can read the nameplate ourselves.

Send that on WhatsApp or by email and you will normally hear back the same working day with pricing by tier, packed dimensions, and a lead time we can actually hold. Vague enquiries get vague answers, so help us help you.

If you are still working out which models belong in your first container, our Transformer Buying Guide: How to Choose and Buy | Wilmall walks through the whole selection process, and the low voltage transformer range shows what we build. There are more country and product guides in our more buying guides section if you want to size a market before you order.

Transformer Wholesale: Questions Buyers Ask Us

These are the five we answer most often before a first bulk order.