An order management system (OMS) collects orders from your sales channels, works out what stock can be sold, reserves stock for each order and decides which location fulfils it. It also handles holds, splits, cancellations and returns.

A warehouse management system (WMS) runs the work inside the warehouse: receiving, putaway to bins, picking, packing, dispatch and stock counts, tracking stock by bin and, where needed, by batch, expiry and serial number.

Is an OMS the same as an ERP?

No. An ERP runs accounting, purchasing and finance. An OMS runs the order between the sales channel and the warehouse. Most brands keep both, connected so that orders, stock and invoices agree.

Which should a D2C brand buy first, an OMS or a WMS?

Usually the OMS, once you sell on a second channel or ship from a second location. Add a WMS when your own warehouse shows mis-picks, stock you cannot find or counts that never match.

Does Fretron CommerceOS include both an OMS and a WMS?

Yes. It covers order management (OMS), warehouse management (WMS) and commerce shipping. Order, allocation, pick and dispatch share one record — no hand-off integration to break.

Which channels does Fretron CommerceOS take orders from?

Amazon, Flipkart and your Shopify store run in production, with orders pulled and inventory published back automatically. Fretron CommerceOS has a Myntra (PPMP) connector for orders, inventory push, ready-to-dispatch labels and returns. It is supported but not yet in production use.

What is the difference between an OMS and a WMS, and which does a D2C brand need?

Updated: 4 Nov 2026

An order management system (OMS) decides what happens to each order: it collects orders from your sales channels, reserves stock and assigns each order to a location. A warehouse management system (WMS) runs the work inside the building: receiving, putaway, picking, packing and dispatch. Most D2C brands need an OMS first, and a WMS once their warehouse gets busy.

The line between the two matters because the problems look alike. Overselling, late dispatch and wrong shipments can start in either system. The sections below explain what each one does, how to tell which problem you have, and what to check when you choose.

What does an order management system (OMS) do?

An OMS sits between your sales channels and your fulfilment. Its job is the life of the order:

Capture. Pull orders from marketplaces, your webstore and other channels into one list, with each channel's SKUs mapped to your own catalogue.
Availability. Work out how much stock can be sold, and publish it back to each channel.
Allocation. Reserve stock for the order and decide which warehouse or store fulfils it.
Control. Hold, split, cancel, backorder or prioritise orders.
Shipping and returns. Pass the order to a courier, and open the return when it comes back.

An OMS knows that stock exists at a location. It usually does not know which shelf it sits on.

What does a warehouse management system (WMS) do?

A WMS runs the physical work inside one or more warehouses:

Receiving. Check inbound stock against the purchase order or ASN, record a GRN and run quality checks.
Putaway. Send each item to a defined bin, so the system location matches the shelf.
Stock by location. Track stock by bin, and by batch, expiry date or serial number where it matters.
Picking and packing. Tell staff what to pick from where, and check each item by scan.
Dispatch. Hand cartons to couriers against a manifest.
Counts. Run cycle counts and adjustments, so the books match the shelves.

What is the difference between an OMS and a WMS?

	OMS	WMS
Main question it answers	Which order, which stock, which location?	Where is it, who picks it, is it right?
Unit of work	The order	The task: a receipt, pick, pack or move
Stock it sees	Quantity per location, reserved and available	Quantity per bin, batch, expiry and serial
Main users	Founders, ecommerce and customer-support teams	Warehouse staff and supervisors
Symptoms when it is missing	Overselling, orders downloaded by hand, cancellations	Mis-picks, stock you cannot find, counts that never match

Does a growing D2C brand in India need an OMS?

You probably need an OMS when one or more of these is true:

You sell on more than one channel, for example your webstore plus Amazon or Flipkart, and update stock on each by hand.
You have oversold, or cancelled orders because a channel showed stock you no longer had.
Orders are downloaded from each panel and merged in a spreadsheet before anyone can pick.
You ship from more than one location, such as two warehouses, or a warehouse and stores.

A brand selling on one webstore from one small stockroom can often wait. The trigger is usually the second channel or the second location.

When should an ecommerce brand move from spreadsheets to a WMS?

Spreadsheets break down in the warehouse before they break down at the order level. Signs it is time:

Pickers rely on memory to find stock, and new staff take weeks to become useful.
Mis-picks and wrong variants show up in returns and marketplace complaints.
Stock on paper and stock on the shelf disagree after every count.
You sell products with a shelf life and need to track batches and expiry dates.
Sale days need temporary staff who cannot learn the layout in time.

How should orders be allocated when you have more than one warehouse or store?

Allocation decides which location fulfils each order. Before you choose software, write your rules down:

Which locations serve which channels. Some marketplace locations can only be fulfilled from one warehouse.
What happens when no single location has the full order. Split the order across locations, ship part and backorder the rest, or wait.
Which orders go first. Express orders, delivery slots and channels with strict dispatch deadlines.
Which batch is reserved first for shelf-life products: first in, first out (FIFO) or first expiry, first out (FEFO).
Who can override the rule, and how that is recorded.

Then ask each vendor which of these rules its software applies and which are left to your team.

Should the OMS and WMS be one system or two?

Both set-ups work. Two separate systems connected by an integration can suit a brand that already has a WMS it likes, or outsources its warehouse. One system for both avoids a hand-off between them. Whichever you choose, check:

Which of your channels connect today, and which are still in progress.
What happens to an order when stock is reserved in one system and picked in the other.
How SKU mapping works for a new channel listing.
How batch and expiry data flows from receiving to allocation.
How the system connects to your ERP or accounting software.

How does Fretron CommerceOS handle orders and the warehouse?

Fretron CommerceOS is order, warehouse and shipping software for Indian consumer brands, running orders, warehouse and delivery on one live record beside your ERP. There is no prebuilt ERP connector. ERP data moves through Fretron's REST API, webhooks or CSV, with the mapping set up per customer. Fretron CommerceOS covers order management (OMS), warehouse management (WMS) and commerce shipping.

Orders (OMS)

Amazon, Flipkart and Shopify run in production, with orders pulled and inventory published back automatically.
Each channel's SKUs and locations are mapped to your catalogue and warehouses; an unmapped SKU doesn't come in until you map it.
Orders are confirmed and allocated per facility, with stock reserved first-in-first-out or first-expiry-first-out (FIFO/FEFO).
Each marketplace location is mapped to the facility that fulfils it.
An allocated order line can be split across facilities.
Orders can be partly shipped, with the rest backordered and re-allocated.
Orders carry a priority, including express and delivery-slot modes.

Warehouse (WMS)

Inbound stock is received against the ASN with a GRN, and QC can accept or reject each piece and quarantine it.
Pickers scan the bin, then the item or serial.
Each piece is scanned at the pack bench before the carton is closed, and cartons are scanned to the courier manifest at handover.
Stock is held on one on-hand ledger, with reservations, batches and serial numbers recorded on it.

Between the two

Order, allocation, pick and dispatch share one record — no hand-off integration to break.

Onboarding scope is set per account.

Read more about order management, the warehouse management system, the full Fretron CommerceOS suite and marketplace integration. For the warehouse steps in detail, see order picking and inventory sync across channels.

Comparing software vendors? See Unicommerce alternatives and competitors, compared.

Frequently asked questions

What is an OMS?: An order management system (OMS) collects orders from your sales channels, works out what stock can be sold, reserves stock for each order and decides which location fulfils it. It also handles holds, splits, cancellations and returns.
What is a WMS?: A warehouse management system (WMS) runs the work inside the warehouse: receiving, putaway to bins, picking, packing, dispatch and stock counts, tracking stock by bin and, where needed, by batch, expiry and serial number.
Is an OMS the same as an ERP?: No. An ERP runs accounting, purchasing and finance. An OMS runs the order between the sales channel and the warehouse. Most brands keep both, connected so that orders, stock and invoices agree.
Which should a D2C brand buy first, an OMS or a WMS?: Usually the OMS, once you sell on a second channel or ship from a second location. Add a WMS when your own warehouse shows mis-picks, stock you cannot find or counts that never match.
Does Fretron CommerceOS include both an OMS and a WMS?: Yes. It covers order management (OMS), warehouse management (WMS) and commerce shipping. Order, allocation, pick and dispatch share one record — no hand-off integration to break.
Which channels does Fretron CommerceOS take orders from?: Amazon, Flipkart and your Shopify store run in production, with orders pulled and inventory published back automatically. Fretron CommerceOS has a Myntra (PPMP) connector for orders, inventory push, ready-to-dispatch labels and returns. It is supported but not yet in production use.

See orders and the warehouse in Fretron CommerceOS.

Bring your channel list and a few sample orders to the demo, and we will walk through how an order from a connected channel would be allocated, picked, packed and handed over.

Book a demo →