New employer reporting (JMHZ) from 2026: who it applies to and how to submit it

As of 1 January 2026, a new legal regulation has come into effect, fundamentally changing the way employers fulfil their reporting obligations. It introduces the unified monthly employer report (JMHZ), which aims to consolidate the previously fragmented submission of data to various public authorities into a single electronic filing.

The previous system was fragmented. Employers had to submit data to multiple institutions, often at different times and in different formats. JMHZ is intended to gradually eliminate this system and establish a unified method of data submission.

Who is required to submit JMHZ?

The obligation will apply to every employer who employs at least one employee, regardless of their size or legal form. For the purposes of JMHZ, an employer is now also considered to be any entity registered as a payer of personal income tax from dependent activities. The obligation will therefore not only apply to traditional employers but also to entities paying remuneration, even if it is subject only to withholding tax.

What will it include?

The scope of the reported data will be significantly broader than before and will directly affect payroll and HR administration.

The report will include in particular:

• identification data of the employer and employee,
• data on the employment relationship,
• information on income,
• data on assessment bases,
• data relevant for insurance and tax purposes,
• information on tax reliefs,
• data on hours worked,
• selected statistical data, such as the highest level of education achieved by the employee.

The specific scope of the data is defined by Government Regulation No. 417/2025 Coll., which also sets out the format and data structure of the submission.

How will the submission work?

The report will be submitted exclusively electronically, always between the 1st and the 20th day of the following calendar month.

It should be noted that any submission made before the 1st day of the relevant period is invalid.

The submission can be made in three ways:

• via the data mailbox of the Czech Social Security Administration,
• by uploading a file to the ČSSZ ePortal,
• by direct connection of payroll software via an API interface.

The report will be submitted through the Czech Social Security Administration, which will ensure its receipt, basic validation and support for employers. However, the entire system falls under the Ministry of Labour and Social Affairs.

When does the obligation start?

Although the legislation has been effective since 1 January 2026, mandatory reporting will only begin on 1 April 2026. At the same time, it will be necessary to submit data retrospectively for the first three months of the year, i.e. January, February and March. These reports may be submitted by the end of June 2026.

What penalties may apply?

Failure to comply with this obligation may result in a fine of up to CZK 5,000 for each employee for whom the report should have been submitted. For larger employers, this may represent a significant penalty.

What change will affect taxes?

Before the introduction of JMHZ, the tax authorities mainly had access to tax filings and employer tax reconciliations, i.e. data necessary for the administration of personal income tax from employment and withholding tax under the previous regime. JMHZ changes this approach. The tax authorities will now receive not only aggregated data for the employer but also detailed data for each employee and their individual employment relationships.

The report will include in particular data relevant for the calculation of tax advances, information on all employment income, including income paid after termination of employment, as well as the results of the annual tax settlement of advances and tax benefits. From 2027, this regime will be followed by the self-assessment of employment income tax and the abolition of withholding tax for such income.

Not sure how to properly implement JMHZ in your company?

We will be happy to assist you with setting up processes, adjusting your payroll agenda and handling the reporting itself, ensuring full compliance with legislation and minimising unnecessary risks.

Contact us