One report, hundreds of data: single monthly employer reporting changes the rules from January 2026

What is the Single Monthly Employer Report and why it’s not just a new form

The Uniform Monthly Employer’s Report (UEMR) is not simply an administrative merger of existing forms into one form. It is a systemic change that fundamentally reshapes the way the state obtains and shares employment, earnings and tax data from employers. One electronic submission will now cover the obligations towards the Czech Social Security Administration, the Ministry of Labour and Social Affairs, the Tax Administration, the Labour Office and other institutions that have been working with separate reports.

The essence of the JMHZ is the centralisation and standardisation of data. The employer will not send different data to different authorities at different times, but will send one report in a structured form every month. From this, the different institutions will take only the data they need. For the state, this means faster and more efficient work with information, but for employers it means higher demands on the quality, completeness and systematic nature of the records kept.

The scope of data covered by the NMHP is significantly broader than what many companies are used to. It is not only about wages and contributions, but also information on individual jobs, hours worked, obstacles to work, commencement and termination of employment. In addition, the data must be consistent with each other as it will be used for multiple legal areas at the same time.

This is why the JMHZ cannot be seen as a technical change to the form. It requires adjustments to payroll and HR processes, linking HR and payroll, and often software changes. Employers who prepare for this change only formally risk that the new ‘one report’ will become a source of knock-on problems across the whole public administration.

Effectiveness of the law versus real start of obligations: the key timeline of 2026

The Uniform Monthly Employer Reporting Act takes effect as early as January 1, 2026, a moment employers should not underestimate. Although the first “sharp” output in the form of a standard single report is not due until April 2026, the obligations associated with the new system kick in significantly earlier and in several follow-up steps.

For the period January to March 2026, the single monthly report is not yet due. However, this does not mean that employers can wait. As early as January, they are already required to keep all the data to the extent required by the new law, i.e., so that it can be sent back later. It is this transitional period that is the most risky in terms of practice – companies have to fulfil their existing obligations (payment of insurance premiums, tax deductions) in parallel and at the same time record data according to the new logic without actually sending them yet.

From 1 April to 30 June 2026, there is a phase of additional reporting. Employers have to retrospectively submit three separate single reports for January, February and March 2026. Only then will the system go into standard mode. The first ‘normal’ single return is submitted for April 2026, by the deadline of 20 May 2026.

The timeline thus clearly shows that the JMHZ is not a one-off start but a process. Employers who do not start to address the new obligations until the spring run the risk of not having complete and correct data for the first few months of the year. It is the backfilling of data that may prove to be the most administratively demanding part of the whole reform.

What data the state will now want and who must report

The Uniform Monthly Employer Reporting will apply to all employers without exception, regardless of size, legal form or number of employees. The obligation applies not only to “traditional” employers with employment relationships, but also to entities employing persons in agreement, small-scale employment or foreign workers. The decisive factor is whether the entity acts as an employer within the meaning of employment, tax and social security law.

The scope of data that employers will have to register and report regularly is significantly wider than before. The JMHZ has three main parts: a summary part with data on the employer, an insurance part relating to social security contributions and an individualised part containing detailed information on individual employees and their occupations. For example, data on the establishment, duration and termination of employment relationships, income, hours worked, obstacles to work, taking leave, temporary incapacity for work or participation in insurance are reported.

A major innovation is the creation of central registers of employers and employees maintained by the Czech Social Security Administration. Each employee will receive a personal identification number and each employment will have its own identifier. Employers will be obliged to keep these registers up to date and report changes within set deadlines.

In practice, this means that data that was previously scattered between different systems or only partially recorded must now be kept in a uniform, structured and complete manner. It is here that the readiness of payroll and HR processes will become apparent – the JMHZ does not accept a ‘simplified regime’ for small or less formal employers.

Penalties, errors and liability: why one wrong report can hurt more than ever

One of the most significant impacts of single monthly employer reporting is the concentration of liability. While individual errors were previously scattered among multiple separate filings and offices, everything is now concentrated into a single report. While this administratively simplifies communication with the state, it also increases the risk that a single error or omission will have simultaneous repercussions against multiple agencies.

The employer is responsible for ensuring that the information provided in the JMHZ is complete, true and submitted on time. If the report is not filed at all or is filed after the deadline, the Czech Social Security Administration will first call for corrections. If the employer does not comply with the obligation even then, he/she runs the risk of penalties. The law allows for fines of thousands to tens of thousands of crowns, and the amount of the fine may take into account, for example, the number of employees involved or the repetition of the violation.

Errors in the content of reports are a specific chapter. Technical defects may lead to the submission being deemed ineffective, i.e. as if it had not been made at all. Formal or factual errors then require the submission of a corrective report, which must be linked to the original dates. Although the system allows for the possibility of corrections and provides feedback, this ‘second chance’ cannot be relied upon as standard operating procedure.

The new scheme therefore emphasises prevention. A single misreport is no longer an isolated problem, but a potential source of knock-on complications – from penalties to delays in employee claims. This is why data quality and internal process control will be more important than ever at JMHZ.

Getting ready on time: software, processes and HR and payroll collaboration

Successfully mastering the single monthly employer report will not be a matter of one click, but the result of systematic preparation. Indeed, the JMHZ strikes at the very heart of payroll and HR processes and forces employers to work with data differently than before. The basic prerequisite is a functional and up-to-date payroll software that will not only be able to produce a single report in the correct format, but above all to keep a continuous record of all the data required by law. Employers should check with software suppliers early on whether the systems will be ready for the new range of data and the new links between them.

But just as important as technology is the review of internal processes. JMHZ links areas that in many companies have operated relatively separately – notably HR, payroll and sometimes external accountants. Information about new hires, changes in hours, work obstacles, or terminations must now be communicated quickly, accurately, and in a standardized format. Any delay or ambiguity can translate into erroneous reporting.

Employers should also use the transition period in the first half of 2026 to train employees who work with the data. JMHZ is not just a new obligation, but a new way of thinking about data – an emphasis on completeness, continuity and long-term traceability. It is the early preparation that will determine whether the single reporting becomes a real simplification or, instead, a permanent source of stress, corrections and penalties.

Summary

The Uniform Monthly Employer Reporting represents one of the biggest changes in employment and payroll administration in recent years. As of January 1, 2026, employers will find themselves under a new regime that centralizes previously fragmented reporting into a single submission, while significantly expanding the scope of data tracked and placing greater demands on its accuracy, completeness, and timeliness. The transition period in the first half of 2026 will be crucial – employers need to record data from January, submit it retrospectively and at the same time prepare for the standard monthly regime from April.

From a practical perspective, this is not just a technical or administrative adjustment, but a change that affects companies’ internal processes, the collaboration between HR and payroll, and accountability to the state and employees. One misreport can have wider implications than before and lead to penalties or complications across the board. Employers that start preparing early, adjust their systems and set clear rules for working with data stand to gain in the long run from the new system. Conversely, those who underestimate the change may face an accumulation of errors at the most sensitive stage of its implementation.