The UID number is a standard field in SAP Business One.

In addition to submitting the recapitulative statement, a valid VAT identification number of the business partner in an EU country is a prerequisite for utilising the tax exemption for intra-Community deliveries. If you do not have a valid VAT identification number of the partner at the time of the delivery or service, the delivery or service is subject to VAT!
You also face a fine of up to €5,000 (26a UStG).
With the add-on Versino Financial Suite you can validate the VAT number of the business partner directly from SAP Business One.
DATEV functions of the Versino Financial Suite
What is the difference between the SAP DATEV interface and the DATEV functions of the Versino Financial Suite? Companies that use SAP Business One ...
SAP Business One and DATEV - Synchronised
The development of the Versino Financial Suite began several years ago as an interface to the DATEV financial system. Initially, we implemented a ...
DATEV and SAP Business One Export & Import
The export and import of data between DATEV and SAP Business One was a major issue with the increasing spread of SAP B1 ...
Versino Financial Suite (DATEV ADDON) - More than imagined
Initially "only" a bidirectional interface to DATEV finance was planned. When we came into contact with more and more users from the finance department of SAP Business One about this development, the ideas came.
VERSINO DATEV Interface/ Financial Suite HANA ready
At the beginning of development, as the name Versino DATEV interface suggests, the focus was on one goal: the transfer and receipt of ...
New functions for the Versino DATEV ADDON
The Versino DATEV ADDON is getting more and more new functions. These have long since gone beyond exporting and importing data between ...