Vendor managed inventory (VMI) is a supply arrangement in which the supplier, not the buyer, decides when and how much to replenish the buyer's stock, using inventory and sales data the buyer shares. The two sides agree target stock levels; the supplier keeps stock within them. Who owns the stock depends on the contract. VMI is about who decides; consignment is about who owns.
- Under vendor managed inventory, the supplier, not the buyer, decides when and how much to replenish, using stock and sales data the buyer shares, within agreed minimum and maximum levels.
- VMI is about who decides; consignment is about who owns. In most VMI programs the buyer owns the stock once received.
- A VMI program runs as a loop: share the data, check stock against targets, propose the order, ship with an ASN, receive and confirm, review performance.
- Buyers get fewer stockouts, leaner stock and less buying work; vendors get real sell-through data, smoother production and fewer rush orders.
- Most VMI failures are data and trust problems, not software problems: late data, wrong targets, misaligned incentives, quiet overrides and no review rhythm.
- Quick-commerce dark stores replenish every 24 to 48 hours and platforms measure fill rates purchase order by purchase order, so brands now run the vendor's half of VMI every day.
SECTION 01VMI in one paragraph
In brief: Vendor managed inventory (VMI) is a supply arrangement in which the supplier, not the buyer, decides when and how much to replenish the buyer's stock, using inventory and sales data the buyer shares. The two sides agree target stock levels; the supplier keeps stock within them. Who owns the stock depends on the contract.
In a standard relationship, the retailer watches its own shelves, decides it is running low and sends the brand a purchase order. Under VMI, that decision moves upstream. The retailer shares what it has and what it is selling, and the brand, as vendor, decides what to send and when, within limits both sides have agreed.
The logic is simple: the vendor sees demand across all its customers, knows its own production and lead times, and has the strongest reason to keep its products in stock. Giving it the replenishment decision usually means fewer stockouts and less excess. For the retailer, it means less buying work and leaner stock.
SECTION 02How a VMI program runs
In brief: A VMI program starts with an agreement on which products and locations it covers, the minimum and maximum stock to hold and the service level to hit. The buyer then shares stock and sales data regularly, the vendor compares it with the targets, proposes or creates the replenishment order, ships it and both sides review performance.
The agreement
Every VMI program rests on a written agreement that covers:
- Scope: which SKUs and which stores, warehouses or dark stores.
- Targets: minimum and maximum stock, usually expressed as days or weeks of cover, and a target fill rate or service level.
- Lead times and order rules: how often orders can ship, minimum quantities and delivery windows.
- Ownership and payment: whether the buyer owns stock on receipt and pays on normal terms, or the vendor keeps ownership until it sells.
- Data: what the buyer shares, in what format and how often.
- Review: the metrics both sides track and how often they meet.
The replenishment loop
- Share the data. The buyer sends stock on hand, sales and open orders, by product and location, daily or weekly.
- Check stock against targets. The vendor compares each location's stock with its agreed minimum and maximum, and with forecast demand.
- Propose the order. The vendor creates a replenishment order to bring each location back within range. Some programs need buyer approval; mature ones do not.
- Ship with an ASN. The vendor ships and sends an advance shipping notice so the buyer can receive against it.
- Receive and confirm. The buyer receives the stock, and the updated figures flow into the next data share.
- Review performance. Both sides track fill rate, stockouts, days of cover and excess, and adjust targets.
Share the data, check stock against targets, propose the order, ship with an ASN, receive and confirm, review performance.
A worked example
A skincare brand supplies a 40-store beauty chain under VMI. The agreement sets a minimum of two weeks and a maximum of five weeks of cover for each SKU in each store, and a 97% fill-rate target. Every Monday the chain shares stock and the previous week's sales by store. One store holds 30 units of a serum that sells 20 a week: one and a half weeks of cover, below the minimum. The brand proposes 60 units, bringing the store to 90, or four and a half weeks, inside the range, and ships it with an ASN on Wednesday.
Note: This example uses illustrative numbers to show the mechanics; it is not a customer program.
SECTION 03VMI vs consignment vs standard buying
In brief: In standard buying, the buyer decides reorders and owns the stock. In VMI, the vendor decides reorders and the buyer usually owns the stock once received. In consignment, the buyer holds the stock but the vendor owns it until it sells. VMI is about who decides; consignment is about who owns.
| Standard buying | Vendor managed inventory (VMI) | Consignment | |
|---|---|---|---|
| Who decides reorders | The buyer | The vendor, within agreed targets | Usually the vendor or by agreement |
| Who owns the stock at the buyer's site | The buyer, from receipt | Usually the buyer, from receipt; the vendor if agreed (vendor-owned inventory) | The vendor, until it sells |
| When the buyer pays | On normal terms after receipt | On normal terms after receipt, unless vendor-owned | Only after the stock sells or is used |
| Who carries the risk of excess | The buyer | Shared: the vendor's targets, the buyer's stock | The vendor |
| Data needed | Purchase orders | Regular stock and sales data by location | Sales or usage reports to trigger payment |
| Best fit | Simple, predictable supply | Steady-selling products across many locations | New or slow-moving products, or buyers short on cash |
The two models combine easily: a vendor can manage replenishment and keep ownership until sale, which is often called vendor-owned inventory. For the full comparison, including how consignment is recorded in the accounts, see our guide to consignment inventory vs VMI.
SECTION 04Benefits for each side
In brief: Buyers get fewer stockouts, leaner stock and less purchasing work. Vendors get direct sight of real demand, smoother production and shipping, fewer rush orders and more control over how their products are stocked. Both sides gain when the targets are right and the data is shared reliably.
| The buyer (retailer, platform or distributor) | The vendor (the brand) |
|---|---|
| Fewer stockouts, because the party that knows supply makes the call | Real sell-through data instead of guessing from purchase orders |
| Less stock held, so less cash and space tied up | Smoother production and shipping, with fewer rush orders |
| Less buying and admin work | More control over availability and range on the shelf |
| A supplier accountable for availability | A stickier relationship with the customer |
VMI also damps what supply chain teams call the bullwhip effect: small changes in shopper demand growing into large swings in orders as they pass up the chain. When the vendor sees the shopper demand directly, it does not have to guess from lumpy purchase orders.
SECTION 05Where VMI fails
In brief: VMI fails when the shared data is late or wrong, when targets are set badly, when the vendor pushes stock to hit its own numbers, when the buyer overrides orders without telling the vendor, or when nobody reviews performance. Most failures are data and trust problems, not software problems.
- Bad or late data. If stock figures arrive a week old or do not match the shelf, the vendor replenishes against a picture that no longer exists.
- Wrong targets. Minimums set too low cause stockouts; maximums set too high fill the buyer's space with slow stock.
- Misaligned incentives. A vendor measured on shipments may push stock; a buyer measured on inventory may cut targets without warning.
- Quiet overrides. When the buyer cancels or changes orders without telling the vendor, trust in the program erodes fast.
- No review rhythm. Without regular reviews of fill rate and excess, small problems turn into a broken program.
SECTION 06The data VMI depends on
In brief: VMI needs stock on hand by product and location, sales or sell-through for the same period, open orders and stock in transit, and the agreed targets, shared on a fixed schedule in a format both systems can read. The vendor also needs its own accurate stock and lead times to promise what it ships.
- Stock on hand by location at the buyer: store, warehouse or dark store.
- Sales or sell-through for the same locations and period.
- Open orders and stock in transit, so nothing is ordered twice.
- Targets and constraints: minimums, maximums, pack sizes and delivery days.
- The vendor's own position: its available stock, its safety stock and its lead times. A vendor that does not know its own stock cannot manage anyone else's.
Format and frequency matter as much as content. Data shared daily through an API or portal supports tight targets; a weekly spreadsheet supports only loose ones.
SECTION 07VMI for brands supplying quick commerce and retail
In brief: Quick-commerce platforms and retail chains increasingly expect brands to behave like VMI vendors: watching sell-through by dark store or outlet, replenishing on short cycles and hitting fill-rate targets, often with penalties for misses. Brands that run this well need one live view of their own stock and a fast path from purchase order to delivery.
For many consumer brands, VMI is no longer a formal program but a daily reality. Quick-commerce dark stores replenish every 24 to 48 hours, platforms measure fill rates purchase order by purchase order, and misses can bring penalties, compliance deductions or delisting. Retail chains share outlet-level sales and expect stock to follow it. Marketplaces with their own fulfillment centers expect brands to keep those locations stocked.
In each case, the brand is doing the vendor's half of VMI: reading the buyer's demand, deciding what to send and getting it there on time. That depends on the brand's own operation: knowing exactly what it holds, where, and what is already committed, and turning each purchase order into an accurate, on-time shipment. Our guide to quick commerce covers that channel's rules in detail.
SECTION 08Where EasyEcom fits
In brief: VMI only works when the vendor knows its own stock as precisely as it knows the buyer's. EasyEcom gives brands one live stock pool across warehouses and channels, handles purchase orders and ASNs, and runs store-level stock with short replenishment cycles for quick commerce, so every replenishment decision rests on accurate data.
EasyEcom's order management system keeps one stock pool across every warehouse and channel, synced in 60 seconds, so the brand always knows what it can promise. For quick commerce, EasyEcom handles purchase orders and ASNs with store-level stock and 24-hour replenishment cycles, the operating model that holds fill rates of 95 to 98% per purchase order store. In the warehouse, inbound stock is received against the ASN, so the buyer's receipt and the brand's shipment match.
Supplying retailers or quick commerce on tight replenishment cycles? Book a demo and we will walk through your purchase-order-to-delivery flow.
Frequently asked questions
What is vendor managed inventory?
Vendor managed inventory (VMI) is a supply arrangement in which the supplier decides when and how much to replenish the buyer's stock, using inventory and sales data the buyer shares. Both sides agree minimum and maximum stock levels, and the supplier keeps stock within them. Ownership of the stock depends on the contract.
How does vendor managed inventory work?
The buyer and vendor agree which products and locations are covered, the stock targets and the service level. The buyer then shares stock and sales data on a schedule, the vendor checks it against the targets, creates replenishment orders, ships them with an advance shipping notice, and both sides review fill rate and excess regularly.
What are the advantages and risks of VMI?
Advantages: fewer stockouts, leaner stock and less buying work for the buyer, and real demand visibility and smoother production for the vendor. Risks: decisions made on late or wrong data, badly set targets, a vendor pushing excess stock, quiet overrides by the buyer and programs that nobody reviews.
What data do you need to share for VMI to work?
Stock on hand and sales by product and location, open orders and stock in transit, and the agreed minimums, maximums and delivery rules, shared on a fixed schedule in a format both systems can read. The vendor also needs accurate data on its own stock and lead times to ship what it promises.
What is a VMI system?
A VMI system is the software and data connection that lets a vendor see the buyer's stock and sales, compare them with agreed targets and generate replenishment orders. It can be a retailer's supplier portal, an EDI or API link, or functions inside the vendor's own order and inventory management system.
What is vendor-owned inventory?
Vendor-owned inventory is stock held at the buyer's location that still belongs to the supplier until it is sold or used, at which point the buyer pays for it. It is often combined with VMI, so the supplier both decides replenishment and carries the stock, and it works much like consignment.
How do you measure whether a VMI program is working?
Track fill rate against the agreed target, stockout frequency by location, days of cover against the minimum and maximum, excess or aged stock at the buyer, and on-time, in-full delivery. Review them on a fixed rhythm with the buyer, and adjust targets when demand or lead times change.