Partial, Supplementary, and Amended Property Tax Returns

Quick Overview: What Type of Tax Return Should You File?

• You generally filea full tax return when a new obligation to report real property has arisen in a given region.
• You can filea partial declaration if you have already filed a declaration in that region and the change applies only to a portion of the registered real estate.
• You filea corrected return if you discover an error before the deadline expires. The new return replaces the original filing.
• A supplementary return addresses an error discovered after the deadline has passed, if that error would have resulted in a higher or lower tax liability.

Therefore, the decisive factor is not only the type of error or change, but primarily whether the deadline for filing the return has already passed.

Not sure whether you should file a regular, partial, amended, or supplemental return? Tell us what has changed regarding your property. An attorney will assess your situation and alert you to any related legal risks.

Who Must File a Property Tax Return

You do not need to filea property tax return every year. The obligation arises only if a specific change occurred in the previous calendar year that affects the amount of tax or the very existence of the tax liability. These situations include:

Acquisition of a new property

The most common reason for filing a return is the acquisition of real estate. If you acquired ownership of land, an apartment, or a house during the previous year, you are required to file a tax return. This applies regardless of whether you purchased the property, inherited it, or received it as a gift. The decisive factor is that you have become the new owner and that this fact is recorded in the real estate registry.

The return is filed for the year following the acquisition—so if you acquired the real estate in 2025, you must file the return by January 31, 2026.

Changes to Property You Already Own

You must also file a tax return if a significant change has occurred with a property you have owned for some time that affects the amount of tax due. Such changes include, for example:

• completion of construction or an addition to a house,
• a change in the use of a building (e.g., converting a garage into a business premises),
• a change in the land area or its reclassification to a different type (e.g., from a garden to a building lot).

Establishment of Co-Ownership

Another situation that triggers the obligation to file a tax return is the acquisition of a co-ownership share in a property. This may involve, for example, an inheritance or the joint purchase of real estate with another person. In such a case, you may file a separate declaration for your share, or you may agree with the other co-owners to file a single joint declaration on behalf of all co-owners.

Partial Transfer of Real Estate

A tax return must also be filed if you have sold or gifted only a portion of a property but remain the owner of another portion of the same property or of another property in the same region. In such a case, you must report the change, as the scope of ownership changes and, consequently, the amount of your tax liability.

A real estate tax return must therefore be filed whenever a change occurs that affects the creation or modification of a tax liability. In some cases, you will need to file a full tax return, while in others, a partial real estate tax return will suffice.

When to File a Partial Real Estate Tax Return

You file a partial real estate tax return when you have already filed a real estate tax return in the past and a change has now occurred that affects the amount of tax but does not apply to the entire property, only to a part of it. In such a case, you do not need to fill out a completely new tax return— you only need to report the changes that have occurred.

You file a partial return, for example, when:

• you purchase another property in the same region (e.g., land, a house, an apartment),
• you sell one property but still own another property in that region,
• you expand, add an extension to, or demolish a building,
• there is a change in the building’s intended use (e.g., you start renting out a garage as a storage space),
• you begin construction or complete a building and begin using it.

When must you file a regular property tax return?

A formal tax return must always be filed whenever a new tax liability arises. This is particularly the case if:

• You are buying your first property: If you have not owned any property before and are purchasing your first one (such as an apartment, house, or plot of land), you become liable to pay real estate tax for the first time. In this case, you must file a regular tax return in which you provide details about this new property.
• You own real estate in multiple regions: Real estate tax is administered according to the region in which the property is located. Therefore, if you already own property in one region and acquire another in a different region, you must file a separate regular property tax return with the tax office responsible for this new region, regardless of whether you have previously filed a return in another region.

In addition to the regular and partial real estate tax returns, there are also supplemental (full or abbreviated) and amended returns.

From a Lawyer’s Perspective: In practice, people most often make a mistake when they own multiple properties and sell one of them or, conversely, acquire another. They automatically assume that it is sufficient to report only the sold or newly acquired property. However, it is also crucial whether the properties are located in the same region and whether the taxpayer has already filed a return with the relevant tax authority.

Amended Real Estate Tax Return

An amended real estate tax return is filed if you discover, after the deadline for the regular return (after January 31), that the tax amount should have been different from what the tax office previously determined. Typically, this occurs when an error or omission is discovered retroactively that affects the tax amount—whether upward or downward.

The “last known tax” is considered to be the amount that the tax authority most recently and definitively assessed, for example, based on a previously filed return or an issued tax assessment notice. As soon as you discover that the tax should have been higher or lower than this last known amount, you are required to file an amended tax return.

The amended tax return must be filed no later than the end of the month following the month in which you discovered the error. If the newly calculated tax is higher, you must also pay the corresponding difference within the same deadline.

There are two types of amended tax returns:

1. Complete amended tax return: In the case of a complete amended tax return, you must list all your real estate properties again, regardless of which ones were specifically affected by the error. This option is particularly suitable if the change affects a large number of properties or if you want to have your entire tax overview reprocessed and presented clearly. In the return, you must also specify the date on which you discovered the error and the difference compared to the last known tax amount.
2. Abbreviated Amended Return: Conversely, an abbreviated amended return is intended for simpler situations where the error concerns only one or a few properties. In such cases, you only need to report the amended information, along with the date the error was discovered and the calculated difference from the original tax amount.

Did you discover the error after the deadline and aren’t sure whether you need to file an amended return? Don’t put off resolving the issue. When filing an amended return, it’s not just the extent of the error that matters, but also the date you discovered it.

Amended Property Tax Return

You must file an amended tax return if you discover an error in a previously filed return before the statutory deadline for filing has expired —that is, before January 31 of the given year, for example. Typically, this may involve an oversight in calculating the tax, an incorrect statement of the land area, or the omission of a specific property.

The amended return replaces the originally filed tax return, whether it was a regular, partial, or supplemental return. The tax office will then only consider the new, amended return and will no longer take the original one into account.

The return is filed on a standard tax return form. In the header, you must clearly indicate the type of return you are filing (regular, partial, supplemental , or abbreviated supplemental) and also check the box indicating that it is an amended return. This fully replaces the original return, without the need to submit any explanation or amendment.

When and Where to File a Real Estate Tax Return

The return must be filed no later than January 31 of the calendar year in which the tax liability arose. For example, if the Land Registry confirmed the transfer of real estate in December 2025, you must file the return by January 31, 2026.

You can find the real estate tax return form on the Financial Administration’s website, or you can pick it up in person at any local tax office.

You can file your return:

• electronically (e.g., via a data box or the Moje daně portal),
• or in paper form, either in person at the tax office’s reception desk or by mail.

The exception is a partial tax return, which cannot be filed electronically. Therefore, if there is a change (for example, you have purchased additional land) and you would like to file the return electronically, you must either file a full tax return—which includes the new changes—instead of a partial return, or file the partial return in paper form.

You must always file your return with the tax office in the region where the property is located. If you own multiple properties in different regions, you must file a separate return with each regional tax administrator.

What happens if you don’t file a tax return?

If you fail to file a tax return at all and the tax office discovers your omission, you face a fine of 0.05% of the assessed tax for each day of delay. The maximum fine is capped at 5% of the tax, but may not exceed CZK 300,000. However, if you file your return no later than five business days after the statutory deadline, the tax office will not impose a penalty.

You may face further penalties if you file your return but report a lower tax amount than what should have been assessed. If the tax office discovers this, it will assess the difference and impose a penalty of 20% of the additional tax due.

An error in the information regarding ownership, area, or use of the property may affect not only your tax liability but also other legal relationships. Our attorneys will review the documents and propose a safe course of action.

Summary

A regular real estate tax return is filed primarily when a new tax liability arises, while a partial return is used for changes concerning a portion of real estate already reported within the same region. An amended return replaces the original filing if you discover an error before the deadline expires. A supplementary return is used when an error is discovered after the deadline has passed. Returns are generally filed by January 31 of the relevant tax year; however, for the year 2026, the deadline fell on February 2, 2026, due to a weekend. Technically, a partial return cannot be filed electronically, but a complete return can be submitted electronically, for example, by using the pre-fill feature in DIS+.