Learn everything you need to know about calibration law–compliant (eichrechtskonform) charging at home. This guide answers the most common questions and gives you an overview of the requirements, standards, and billing methods.
Calibration law–compliant charging means that the measuring device and the entire measurement and billing system of a charging station comply with the requirements of German metrology law (MessEG/MessEV). This ensures that the exact amount of energy charged is billed correctly and transparently, so both employees and employers can verify the data at any time.
Calibration law compliance is essential to guarantee transparency and fairness when billing electricity used for charging company cars at home. It protects both the employee and the employer from potential billing errors or manipulation. For employees who are reimbursed by their company for the electricity used, this provides legal security. The data can also serve as verifiable evidence for tax authorities.
For purely private charging through a personal household electricity meter, calibration compliance is usually not required. However, once electricity consumption is billed to a third party – for example, when an employer reimburses employees for charging company cars at home – calibration law requirements apply.
Calibration-compliant wallboxes must be tested and certified by an accredited institution. In Germany, this includes the Physikalisch-Technische Bundesanstalt (PTB), the VDE, and other certified testing bodies. These institutions ensure that the wallbox meets legal standards and functions reliably. The manufacturer’s production process must also be certified so that every wallbox sold matches the approved prototype.
Key requirements for calibration-compliant wallboxes include:
Manufacturers usually indicate this in the technical specifications, often with labels such as “eichrechtskonform” or “conformity assessed.” Certificates or seals can also serve as proof but are not always mandatory. When in doubt, check the product documentation and the manufacturer’s declaration of conformity.
Yes. Whenever energy is billed by the kilowatt-hour to a third party, the same legal requirements apply to both AC and DC charging systems. The technical design may differ, but the legal framework is identical.
It ensures transparent, auditable billing, builds trust among employees, improves cost control, and provides legally secure proof for reimbursements. For companies with electric vehicle programs, these are strong arguments for implementing compliant systems.
Calibration-compliant systems are more complex and typically more expensive to purchase and maintain. They may also require regular inspections or device replacements. These costs are offset by the gain in legal security and billing transparency.
Typical data points include:
All datasets are digitally signed and protected against any later modification.
MID stands for Measuring Instruments Directive, an EU regulation for measuring instruments. A MID-compliant meter guarantees measurement accuracy but does not automatically meet the broader German requirements for signature, data access, and full system verification.
MID compliance focuses on measurement accuracy according to EU law. Calibration law compliance in Germany, however, covers the entire system – including data security, tamper protection, digital signature, and verifiability – and must be officially approved.
Because German calibration law looks at the complete measurement chain. A single MID meter does not ensure the required data signing, immutability, or transparent verification demanded by German regulations.
If no billing to unknown third parties takes place and only known users are involved, a MID meter may be sufficient. Examples include a dedicated home wallbox used only for a company car or when landlords allocate costs to known tenants. It is always advisable to assess each case individually.
Billing is based on digitally signed kWh readings. The data is securely stored and transmitted to a backend system. Users can verify the underlying data sets using transparency software listed by the PTB.
Yes. Measurement accuracy must be verified at defined intervals. In practice, this often means replacing the measuring unit rather than recalibrating it on-site, depending on the device and usage pattern.
According to market data, calibration-compliant AC wallboxes start at around €1,500. Models with dual charging points or extended functionality are significantly more expensive. Installation, maintenance, and inspection costs may also apply.
The information above provides a practical overview and does not replace legal advice. For specific cases, always refer to the product documentation or consult your metering point operator, manufacturer, or a qualified legal advisor.
