In addition to being used for the eID function, the chips in German ID cards and electronic residence permits can be read on site. This involves reading a chip electronically in the presence of the respective citizen and transferring personal data such as their name and address onto forms used by a service provider. Besides taking less time than it would to copy such information manually, this method prevents related errors.

As with the eID function, the secure data transmission and mutual authentication between an ID card's chip and the device reading it also take place when reading a card on site. Companies and public authorities that wish to offer this function require government authorisation to read cards on site and a corresponding reader.

Pursuant to Section 18a of the German law governing ID cards (Personalausweisgesetz), data may only be read from a German ID card or residence permit after the holder has been identified via the photograph printed on the card or permit and has granted their consent. On-site access to this data requires the access number (CAN) that is printed on the front of an ID card to the right of its date of validity.

As in the case of the eID function, it is not possible to read the data on an ID card's chip on site (in public places, for instance) without the holder noticing. The chip will only grant access to the data when the corresponding PIN (which is known only to the citizen in question) or the CAN printed on the respective ID card is transmitted to it.