What is serial number tracking in a warehouse?

Serial number tracking means recording the unique serial number of every individual unit and following it through the warehouse: captured at receiving, stored in a known bin, scanned at picking and packing, saved against the order and checked again if the unit comes back. It shows exactly which unit went to which customer, which matters for warranty, returns and recalls.

What is the difference between a serial number and a batch or lot number?

A serial number identifies one unit; no other unit has it. A batch or lot number is shared by all the units made in one production run or received together. Batch tracking tells you which group a unit belongs to, for expiry dates and recalls. Serial tracking tells you exactly which unit it is, for warranty and returns checks.

What is the difference between a serial number and a SKU?

A SKU identifies a product variant in your catalogue, such as "power bank, 10,000 mAh, black", and every unit of that variant shares it. A serial number identifies one physical unit of that SKU. Stock is counted by SKU, while serials tell you which individual units are in stock, which were shipped and which came back.

What is serialised inventory?

Serialised inventory is stock in which each unit carries its own serial number and is tracked individually. Instead of "40 units of SKU X in bin A-03", the record shows the 40 serial numbers in that bin. It is used for high-value, warrantied or regulated goods, where knowing the exact unit matters for service, returns or compliance.

How does serial number tracking help with returns and warranty claims?

When a return or warranty claim comes in, the serial on the unit is compared with the serial recorded on the original order. If they match, the claim relates to the unit you sold. If not, the item is a different unit, possibly a swap, and goes for investigation instead of a refund or straight back to stock.

When should a brand use serial tracking instead of batch tracking?

Use serial tracking for high-value, warrantied or regulated products such as electronics, appliances and tools, where each unit has its own service history or is a target for returns fraud. Batch or lot tracking can be enough for cosmetics, food and fashion, where units in a batch are interchangeable and the main concerns are expiry and recalls.

Is an IMEI number the same as a serial number?

Not quite. An IMEI (International Mobile Equipment Identity) identifies a mobile phone on mobile networks. In India, the Department of Telecommunications' CEIR portal lets users block a lost or stolen handset. A phone also has the maker's serial number, which the maker uses for warranty and service. A warehouse selling phones can record both against each unit.

What is the difference between a lot number and a batch number?

In everyday warehouse use, the two mean nearly the same thing: a code shared by units produced or received together. Where a difference is made, a batch is one production run and a lot is a quantity made or received under the same conditions, which may span or split batches. Food labels in India carry a batch, code or lot number.

What is serial number tracking?

Serial number tracking records a unique number for each individual unit of a product and follows that unit through receiving, storage, picking, packing, dispatch and returns. Unlike a batch or lot number, which is shared by many units, a serial number belongs to one unit only, so the warehouse knows exactly which unit went to which order.

Phones and appliances carry a maker’s serial number, and phones an IMEI, for warranty and service. To find your own device’s number, see the maker’s support page. This page is about tracking serials in a warehouse.

How serial number tracking works in an Indian D2C or omnichannel warehouse

The flow

Capture at receiving: scan the maker’s serial on each unit at the GRN, or generate serials from a series and stick a label on each unit.
Store: the unit is put away like any other stock, and the system knows which serials sit in which bin.
Scan at pick and pack: the picker or packer scans the serial, so the order records the exact unit.
Record on the shipment: the serial is saved against the order and the AWB number.
Check at return: the returned unit’s serial is compared with the one shipped on that order.

Example: a returns check. All data is illustrative.

100 power banks are received with serials PB-0101 to PB-0200.
Order 5521 ships the unit PB-0157.
A return for order 5521 arrives carrying PB-0433, which is not the unit shipped and not from this delivery.
The return goes to a returns-fraud check instead of back to stock.

Serial number vs other identifiers

Identifier	Identifies	Shared by	Example use
Serial number	One individual unit	No other unit	Warranty, returns check
Batch or lot number	A production run or delivery	All units made or received together	Expiry, recalls
SKU	A product variant in your catalogue	All units of that variant	Stock and orders
GTIN	A trade item, worldwide	All units of that variant	Barcode scanning, listings
IMEI	One mobile phone, on mobile networks	No other phone	Identifying a handset, for example when it is lost or stolen

When to serialise

Serialise high-value, warrantied or regulated items, such as electronics, appliances, power tools and premium watches, and items exposed to returns fraud.
Batch or lot tracking can be enough for cosmetics, food and fashion, where units of one batch are interchangeable and expiry or recall is the main concern. See batch and lot tracking.

Capture at receiving, at pack, or both. Capturing at receiving means every unit in stock is known, which helps with counts and recalls, but it takes time at the dock. Capturing only at pack is faster to receive but leaves stock untracked until it ships. Both together give the full trail.

Common mistakes

Capturing serials at dispatch only, so there is no record of which units came in.
Typing serials by hand instead of scanning, which lets typing errors into the record.
Not checking the serial at returns, so a different or damaged unit goes back to stock.
Serialising low-value, interchangeable items, which adds a scan to every unit for little benefit.

Serial capture rate = units shipped with a serial recorded ÷ serialised units shipped × 100. Example: 1,176 of 1,200 = 98%.
Return serial mismatch rate = returns whose serial doesn’t match the unit shipped ÷ returns checked × 100. Example: 4 of 250 = 1.6%.
Units per hour at receiving = serialised units received ÷ hours. Example: 600 units in 4 hours = 150 an hour.

Serial number tracking in the Indian context

Mobile phones and IMEI. The Department of Telecommunications’ Sanchar Saathi CEIR portal (ceir.gov.in) lets users block a lost or stolen mobile handset and unblock it once it is found. A brand selling phones can record the IMEI as well as the serial, so a returned handset can be matched to the one sold.
Food and cosmetics. These can be tracked by batch rather than serial. Food labels carry a batch, code or lot number under the FSS (Labelling and Display) Regulations, 2020 (regulation 5(9)).
Marketplaces. Any rule on capturing serial or IMEI numbers for marketplace orders is set by each marketplace. Check its seller portal.

How Fretron CommerceOS fits

Fretron CommerceOS is order, warehouse and shipping software for Indian D2C, retail and omnichannel consumer brands. It is a separate product from Fretron’s freight TMS.

In Fretron CommerceOS, serial numbers can be generated from a series. Picking is scan-guided: bin, then item or serial. Serials are held in the same stock ledger as batches.

Questions and answers

What is serial number tracking in a warehouse?: Serial number tracking means recording the unique serial number of every individual unit and following it through the warehouse: captured at receiving, stored in a known bin, scanned at picking and packing, saved against the order and checked again if the unit comes back. It shows exactly which unit went to which customer, which matters for warranty, returns and recalls.
What is the difference between a serial number and a batch or lot number?: A serial number identifies one unit; no other unit has it. A batch or lot number is shared by all the units made in one production run or received together. Batch tracking tells you which group a unit belongs to, for expiry dates and recalls. Serial tracking tells you exactly which unit it is, for warranty and returns checks.
What is the difference between a serial number and a SKU?: A SKU identifies a product variant in your catalogue, such as "power bank, 10,000 mAh, black", and every unit of that variant shares it. A serial number identifies one physical unit of that SKU. Stock is counted by SKU, while serials tell you which individual units are in stock, which were shipped and which came back.
What is serialised inventory?: Serialised inventory is stock in which each unit carries its own serial number and is tracked individually. Instead of "40 units of SKU X in bin A-03", the record shows the 40 serial numbers in that bin. It is used for high-value, warrantied or regulated goods, where knowing the exact unit matters for service, returns or compliance.
How does serial number tracking help with returns and warranty claims?: When a return or warranty claim comes in, the serial on the unit is compared with the serial recorded on the original order. If they match, the claim relates to the unit you sold. If not, the item is a different unit, possibly a swap, and goes for investigation instead of a refund or straight back to stock.
When should a brand use serial tracking instead of batch tracking?: Use serial tracking for high-value, warrantied or regulated products such as electronics, appliances and tools, where each unit has its own service history or is a target for returns fraud. Batch or lot tracking can be enough for cosmetics, food and fashion, where units in a batch are interchangeable and the main concerns are expiry and recalls.
Is an IMEI number the same as a serial number?: Not quite. An IMEI (International Mobile Equipment Identity) identifies a mobile phone on mobile networks. In India, the Department of Telecommunications' CEIR portal lets users block a lost or stolen handset. A phone also has the maker's serial number, which the maker uses for warranty and service. A warehouse selling phones can record both against each unit.
What is the difference between a lot number and a batch number?: In everyday warehouse use, the two mean nearly the same thing: a code shared by units produced or received together. Where a difference is made, a batch is one production run and a lot is a quantity made or received under the same conditions, which may span or split batches. Food labels in India carry a batch, code or lot number.

See CommerceOS on your own data.

Book a demo →

Next step: order picking methods.

Last reviewed: 7 November 2026 by Fretron.

Sources

Central Equipment Identity Register (CEIR), Sanchar Saathi. Department of Telecommunications, Ministry of Communications. https://www.ceir.gov.in/Home/index.jsp (site last updated 30 Oct 2026; accessed 5 Nov 2026).
Food Safety and Standards (Labelling and Display) Regulations, 2020, compendium Version VI (22 Feb 2023), regulation 5(9). FSSAI. https://fssai.gov.in/upload/uploadfiles/files/Comp_Labelling.pdf (accessed 5 Nov 2026 for batch 3, task ea5c4bd1).