If purchase costs are below 410 Euro, then the service life does not play a role and your can immediately deduct the entire cost in the same year it was accrued.
The limit of € 410 is considered the net amount; ie. an asset can be deducted in one go if it is up to € 487.90. Please enter the gross amount if you are a small business owner. Non-small business owners can only enter the net amount here and submit the VAT (input VAT) separately.
If the purchase price exceeds this limit, then you have to split this over the year of expected use.
The period the asset (e.g. laptop, desk or even work clothes) is used is considered the service life of it.
Example:
On January 1, 2017 you purchase a laptop for 900 Euro (incl. VAT). The 410 Euro limit is exceeded here and you can completely deduct your purchase in one go for the same year of purchase. A service life of three years is accepted for laptops.
In this case, this means the 900 Euro purchase price must be divided over three years:
2017: € 300
2018: € 300
2019: € 300
The service life for most items are set such a way in the tool that you only have to enter the date of purchase as well as the purchase price. Please notice that you must always enter the full purchase price, so that the deduction is automatically calculated.
In some cases, you have to enter the service life manually.
Here is the tax office’s official “Service life” table. Should you use the asset over a shorter period and you can prove this, then you are allowed to enter a shorter service life.