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FIFO/Serial Number Tracking


FIFO is another type of costing method (see Cost Methods). Its similar to average but we need to track each cost of each item.

Tracking Serial Numbers

Rather than track each and every single unit, the system tries to work more efficiently. Exactly what information is recorded depends on how the item is set up (using the Serial Number Tracking option on the Advanced tab of Items). There are four options.

Do not track serial number

Does not track serial number at all. The user interface for POS and inventory does not change.  

Track batch/use by date

We track batches of products by either a batch number of use by date. In inventory we need to specify which batch we are working on. In POS, we assume we are using the oldest product first so there is no change to the interface. The user can record the Batch# and/or Use By Date for each batch.

Track Supplier Serial Numbers

We track specific units by the supplier serial number. In inventory we have to indicate the specific units and in POS we have to select specific units to sell. As well as the serial number, the user can record the Batch# and/or Use By Date for each unit.

Track Our Serial Number

We track specific units by our internal serial number. In inventory we have to indicate the specific units and in POS we have to select specific units to sell. You would use this option if you wanted to track specific items but the supplier has not provided serial numbers. As well as the serial number, the user can record the Batch# and/or Use By Date for each unit.

The system will always keep track of a batch of items. This contains details about the specific transaction that was created, the number of units in the batch, the current number of units and the cost of the items. If we receive 10 units, we would create a single batch with an original and current quantity of 10. This is more efficient than creating an entry for each unit of stock.

If we are tracking serial numbers, the system will create a serial number record for each unit and link this to the batch (so we can get the cost).

See How Do I Set Up Tracking Serial Numbers? for more information.

Increasing Stock

Increasing stock with FIFO is straight forward. The system will create a new batch for the quantity and cost. If we are tracking serial numbers, these will be created.

Decreasing Stock

Decreasing stock is a little more complicated. If we are not tracking serial numbers or batches at all, we simply look for the oldest batch. We reduce the current quantity by the required amount. If we still have more units to use, we go to the next oldest batch.




Existing batch



Decrease by 2 units

Updated batch




Existing batches






Decrease by 12 units

Updated batches






If we are tracking batches, we reduce the batch record as above but we reduce the selected batch, not the oldest one.

If we are tracking serial numbers then we update the serial number record to show it has been used and then reduce the current quantity of the batch record the serial number was linked to.

POS Allocations

When we are doing POS customer orders/laybys/CODs, there is an allocated quantity on the batch to show that the stock has been allocated but not actually used. Similarly, if we are tracking serial numbers, the status of the serial number record is updated  to show its been allocated for use.

Data Entry

As explained above, the FIFO details are recorded in batches and serial numbers. However, these details are only recorded when the inventory transaction is accepted and stock details are updated. The serial number details entered in an inventory transaction are saved in a different area. When the transaction is accepted, the system will use these details to alter the actual batches and serial numbers.

When an item is added to a transaction, the system will check the item and if it requires some form of batch or serial number tracking, it will add an extra tab to the item entry window. If you are increasing stock, you will need to enter all the details of the items. The exact details will depend on the method of tracking. If you are tracking only batches, the system will ask you or a Batch#, Use By Date and Quantity. If you are tracking by supplier serial number, you will be able to enter a Supplier Serial Number but you won't need to enter the Quantity (which is assume to be one since a serial number is attached to a single unit).

If you are decreasing stock, the system will show you what stock is available and allow you to select the details you want to use for this transaction. The first tab will simply show you what has been selected to use for this batch.

Press the Edit button to see the actual items available. You can then select the items to use. These will be added to the first grid.

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