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Serial Number Tracking

5 min read

Published April 12, 2026

Updated May 24, 2026

Enabling Serial Number Tracking

Serial tracking is configured per item during creation. Once enabled, every unit of that item must have a unique serial number assigned.

  1. When creating a new item, toggle on Serial Number Tracking.
  2. Track Stock must also be enabled, serial tracking requires quantity management.
  3. Enter serial numbers in the text area, one per line, matching the Initial Stock quantity.
  4. Fixmo validates that all serials are unique within your shop before saving.

Note

Serial tracking cannot be toggled off once the item has been created with serials. Plan your tracking needs before creating the item.

Adding Serials During Restock

Every time you add stock to a serialized item, you need to provide serial numbers for the new units. This ensures every unit in your system is individually identifiable.

  1. Open the Restock dialog from the item's action menu.
  2. Enter the quantity being added.
  3. In the Serial Numbers text area, enter one serial per line.
  4. A progress indicator shows how many serials you have entered vs. the required quantity.
  5. The system warns you if the count does not match before allowing submission.

Serial Number Statuses

Each serial unit in Fixmo has a status that reflects its current state in the lifecycle. Statuses change automatically as items are sold or used, and can also be updated manually.

  • In Stock, the unit is available in inventory, ready to be sold or used.
  • Sold, the unit has been sold through POS and is linked to a sale record.
  • In Repair (Used in Repair), the unit is currently being used as a part in an active repair.
  • Repair Done (Completed Repair), the repair using this unit has been completed.
  • Returned, the unit was returned, either from a sale or a repair.
  • Defective, the unit has been marked as defective and removed from available stock.

Managing Serials from the Edit Page

The item edit page includes a Serial Numbers tab that serves as the central hub for viewing and managing all serial units belonging to that item.

  1. Open the item's edit page.
  2. Click the Serial Numbers tab.
  3. Browse the complete list of serials with their status, branch, and linked transactions.
  4. Use the search field to quickly find a specific serial number.
  5. Click on a serial to update its status or add notes.

Serials in Sales & Repairs

When a serialized item is involved in a sale or repair, Fixmo requires you to select which specific serial unit is being used. This creates a traceable link between the transaction and the individual unit.

  • POS checkout & invoices, when adding a serialized item to a sale or invoice, you choose which serial number to sell. Selling several units of the same product? Raise the line quantity and pick one serial per unit on the same line, there's no need for a separate line each.
  • Repair parts, when adding a serialized item as a repair part, you select the specific serial unit being consumed.
  • Linked documents, each serial shows which sale code or repair code it is associated with, making it easy to trace history.

Cross-Variant Serial Validation

For variable products, Fixmo enforces serial uniqueness across all variants of the same product, not just within a single variant.

  • When you assign or pick a serial number, the system checks every variant of that product.
  • If the serial is already assigned to a different variant (e.g., 'Black' already has SN-001, and you try to assign SN-001 to 'White'), the action is blocked.
  • The error message names the conflicting variant and serial so you can resolve the conflict immediately.
  • This prevents a single physical unit (identified by serial) from appearing in multiple variant pools simultaneously.

Warning

Always assign a unique serial number to each physical unit. Sharing a serial across variants is physically meaningless and Fixmo blocks it at save.

Serial Lookup Fallback

Fixmo uses a fallback mechanism when looking up a serial's history. If a serial cannot be found in the serial-tracking table (e.g., from older stock entries), the system checks the SaleItem record's serialNumber field as a secondary source.

  • This ensures that serials entered before serial-tracking was enabled on an item are still searchable.
  • The fallback is transparent, the Warranty & Serials page and serial search handle it automatically.
  • If you imported items or performed early restocks without serial tracking, those unit histories are still retrievable through search.

Frequently asked questions

Serial numbers must be unique within your shop. Once a serial is created, it remains in the system with its status history. If a unit is returned, the serial status changes to Returned but the serial number itself is not freed for reuse on a different item.

When a serialized item is sold through POS, you select which specific serial to sell. That serial's status changes from In Stock to Sold, and it is linked to the sale transaction for traceability.

When a serialized item is added as a repair part, the serial's status changes from In Stock to In Repair (Used in Repair). When the repair is completed, the status updates to Repair Done (Completed Repair). The serial is linked to the repair record.

Yes. From the item's Serial Numbers tab on the edit page, or through the Warranty & Serials page, you can update a serial's status and add notes. Available statuses are In Stock, Sold, In Repair, Repair Done, Returned, and Defective.

Use the Restock action on the item. When restocking a serialized item, the serial numbers text area appears and you must enter one serial per line. The number of serials must match the restock quantity exactly.

No. Serial number tracking is an opt-in feature enabled per item. It is ideal for high-value items, electronics, or anything requiring individual unit traceability. Most consumable parts and low-value items do not need serial tracking.