JMHZ 2027 changes will give Czech tax authorities more detailed payroll information and support automated checks on employee tax reliefs. For employers, preparation means reviewing both the accuracy of submitted information and the processes used to collect it.
The Single Monthly Employer Report, known in Czech as Jednotné měsíční hlášení zaměstnavatele (JMHZ), brings together reporting obligations previously spread across several institutions. Its development also raises a broader question: how should more effective public administration be balanced with the protection of employee information?
October’s official clarifications explain how tax checks will work from 2027. Earlier reporting on data incidents and employee concerns provides important context. Together, these developments show why payroll compliance and data protection need to be considered within the same operational framework.
What Changes Under JMHZ 2027?
The update builds on a reporting system already introduced in 2026. It is a further stage of implementation, rather than the launch of an entirely new obligation.
As explained in Axevera’s earlier article on single monthly employer reporting in the Czech Republic, the reform brings previously separate submissions into one reporting framework.
The Ministry of Labour and Social Affairs announced in October that it had finalised changes taking effect from 1 January 2027. These include adjustments to reported information and technical documentation for payroll software providers.
Additional tax information will cover matters such as the signing date of an employee’s taxpayer declaration and information concerning tax reliefs, bonuses and annual reconciliation. Some information is submitted monthly, while certain annual totals follow a different timetable.
For payroll teams, the task is to understand which fields apply to each employee and when to report them. A software update does not replace checking records and supporting documents.
For foreign groups, the first question is which entity reports. Employers with staff in the Czech Republic fall within the system, which in practice usually means the group’s Czech-based entity. Foreign employers that post staff to the Czech Republic should check their case separately: depending on the situation, a posting is reported through JMHZ, through the SÚIP portal, or through both.
How Will Automated Tax Checks Work?
The Czech Financial Administration has confirmed that it will verify the correctness of JMHZ information from the beginning of 2027.
In an official clarification published on 22 October, it explains that the system supports ongoing automated checks and earlier identification of errors and inconsistencies.
A separate clarification on tax relief verification describes how more detailed information will help assess child-related tax benefits, other reliefs, bonuses and annual reconciliation. One example is an employee signing a taxpayer declaration simultaneously with multiple employers, potentially creating incorrect or duplicate claims.
Automated verification is not the same as a formal tax inspection of every employer. The confirmed change concerns more systematic checks of submitted information.
The Financial Administration states that these checks concern information already covered by standard payroll procedures. JMHZ 2027 makes it easier for authorities to compare and assess that information. Consequently, consistency between employee declarations, payroll calculations and reports becomes especially important.
Why Has Employee Data Privacy Become Part of the Debate?
Under JMHZ 2027, effective checking depends on reliable access to detailed information. That creates an equally important responsibility to prevent access by people or organisations without the appropriate entitlement.
In June, Podnikatel.cz reported a JMHZ data incident in which some employers could see information about workers employed by other businesses. The Czech Office for Personal Data Protection (ÚOOÚ) told the publication that it had received approximately 50 complaints and submissions.
The ministry acknowledged the incident and said it had taken corrective action and introduced additional technical and control measures.
A July follow-up by Novinky reported a broader scope than initially communicated. Citing information obtained from the ministry, it said the incident concerned 7,281 employees and information sent to almost 3,400 businesses.
These reports concern events in 2026; they do not establish that the same problem remains unresolved today. They explain why employees and employers may seek clarity about access controls, incident handling and accountability.
What Safeguards Protect Employee Information?
The JMHZ 2027 privacy debate extends beyond technical data leaks. It also concerns which information employers request, why it is needed and how it may affect the employment relationship.
An April explanation by Seznam Zprávy documented uncertainty over what workers should provide. It also reported concerns that disclosing disability-related information could expose employees to disadvantage or discrimination.
Employees therefore need clear explanations of reporting requirements. Meanwhile, employers need to distinguish required information from unnecessary additional questions.
The official ČSSZ document on JMHZ security describes access restrictions based on legal entitlement and working roles. It also describes access logs that can be audited and limits on the purposes for which institutions receive information.
The document states that employers are not entitled to access information reported about a worker by another employer. These safeguards describe the intended system; the earlier incidents demonstrate why implementation matters.
How Should Employers Prepare for JMHZ 2027?
Preparation should bring together payroll accuracy, reporting procedures and employee communication. A focused review can cover four areas:
- Payroll software: confirm support for the relevant 2027 reporting changes.
- Employee records: check that declarations and supporting documents match payroll information.
- Responsibilities: identify who checks submissions, investigates inconsistencies and manages corrections.
- Data handling: review access permissions and explain why information is requested.
These are practical preparation steps, rather than a separate list of new statutory obligations.
Conclusions
JMHZ 2027 makes the relationship between reporting and verification more immediate. Authorities expect to identify inconsistencies earlier, while employees need confidence that their information is collected and used appropriately.
For businesses in the Czech Republic, the priority is a payroll process that produces accurate reports and handles personal information responsibly. Axevera’s payroll and accounting services can support a review of records, calculations and reporting processes ahead of the next phase. Contact Axevera to discuss your company’s preparation.
Sources: Czech Financial Administration (22 October 2026), MPSV (5 October 2026), ČSSZ, Podnikatel.cz (8 June 2026), Novinky (16 July 2026) and Seznam Zprávy (9 April 2026). Source articles and official documents are linked above. Information checked as of 26 October 2026.
JMHZ 2027: Common Questions from Employers
What is JMHZ?
The Single Monthly Employer Report (Jednotné měsíční hlášení zaměstnavatele, JMHZ) brings together reporting obligations that were previously spread across several institutions. It was introduced in 2026, and the changes taking effect from 1 January 2027 are a further stage of the same reporting system, not a new obligation.
When did JMHZ start and what changes in 2027?
JMHZ started on 1 April 2026. From 2027 employers report additional tax information, such as the date the employee signed the taxpayer declaration, student relief and the annual total of monthly tax bonuses, which is reported in the January submission. Some annual totals are first reported in January 2028.
Yes. The Czech Financial Administration states that the correctness of reported data will be verified from the start of 2027. JMHZ was designed for continuous automated checks and earlier detection of errors and inconsistencies. According to the Financial Administration, this is not about verifying new facts, but about checking data already covered by standard payroll procedures.
Do foreign employers posting staff to the Czech Republic use JMHZ?
Sometimes. According to Ministry of Labour guidance, a non-EU employer posting a worker to the Czech Republic meets its notification duty through JMHZ. For postings from EU member states, reporting is usually made through the SÚIP portal, and also through JMHZ if the posting creates a Czech income tax or social insurance obligation.
Can an employer see another employer’s data?
No. The ČSSZ document on JMHZ security states that an employer has no access to data an employee provided to another employer, and that access is limited by legal entitlement and role and recorded in auditable logs. A 2026 bug did let some employers see workers of other companies; the ministry acknowledged the incident and introduced additional technical and control measures.
How should employers prepare for JMHZ 2027?
Review four areas: payroll software support for the 2027 changes, consistency between employee declarations and payroll records, responsibilities for checking and correcting submissions, and data handling, including access permissions. A software update does not replace checking records and supporting documents.
