Find the parcel number for a German address

An address names an entrance; a parcel (Flurstück) names a piece of land. Contracts, authorities and notaries go by the official designation in the real-estate cadastre: Gemarkung, Flur where the state uses it, and parcel number. You can find these free of charge in your state's map viewer. That view is a starting point, not an official extract.

Gemarkung, Flur and parcel number

The land register describes plots by the state's official record, which is the cadastre (§ 2(2) GBO). In Bavaria, Art. 5(3) sentence 2 BayVermKatG makes the parcel the unit in which land is recorded. Brandenburg defines it in § 8(3) BbgVermG as a part of the earth's surface held in the cadastre under its own designation.

In practice the designation has three parts:

• Gemarkung: the cadastral district, often the name of a village or part of town. It is always given.
• Flur: a subdivision of the Gemarkung. It does not exist everywhere; the help page of the Hamburg parcel search notes that some districts have no Flur and the field then stays empty.
• Parcel number: often written as a fraction such as 16/24 (numerator and denominator). Where there is no denominator, some search forms expect a 0, as the Hamburg help explains.

The national ALKIS data model treats Gemarkung and parcel number as mandatory and the Flur as optional. When you write to the municipality, the building authority or the notary, use the parts your state actually records. A house number alone gets you nowhere there.

Finding the parcel for an address

The usual route is the state's map viewer. Search for the address, zoom to the plot and click inside it. The viewer then shows Gemarkung, Flur, parcel number and usually the official area. In North Rhine-Westphalia the viewer is TIM-online, and Geobasis NRW publishes cadastral data free of charge as open data (simplified ALKIS, NRW). In Brandenburg it is the Brandenburg viewer, and under § 10(2) BbgVermG digital base data there is free for any use. The other states' viewers are listed in Geoportals of the 16 states.

After the click, ask three questions:

1. Does the outline match the land being sold, or does the listing include a strip of path, a neighbouring piece or a second parcel?
2. Do Gemarkung, Flur and number match the listing and the draft contract?
3. How recent is the map? After a division, old and new numbers can appear side by side in documents for a while.

A building can stand on two parcels, and one parcel can carry several house numbers. That is why the map check comes before any enquiry to the municipality, the building authority or the notary. The checklist for buying land puts this step first.

ALKIS shows the land, the Grundbuch the rights

ALKIS is the official cadastral information system, the standard shared by the state surveying authorities. According to the Bavarian surveying administration, it holds parcels, buildings, owners, actual land use and soil valuation. The Flurkarte is the map edition of that record, with boundaries, numbers, buildings and addresses.

The land register answers other questions: section I names the owner, section II easements and restrictions, section III mortgages and land charges. The register takes the area figure from the cadastre, and that figure is not covered by public faith under § 892 BGB. The boundary line as the cadastre shows it is covered, according to the prevailing view. So if the register says 1,000 m² and a survey finds 920 m², the register gives you no claim to the difference.

Access rules differ. In Bavaria anyone may look up the parcel designation; owner data requires a legitimate interest (Art. 11(1) sentence 3 BayVermKatG). Brandenburg likewise releases personal data to private parties only with a legitimate interest (§ 10(1) BbgVermG). The public map without owner names is therefore the normal first step. The land register extract comes later, from the seller, with an authorisation or through the notary; Applying for a Grundbuch extract explains how, and Grundbuch and ALKIS explains how to match the two records.

15 states open, Bavaria with limits

Outside Bavaria the state viewers show boundaries and numbers freely. GrundCheck therefore reads the official parcel boundary in 15 states; in Bavaria the order map works with a confirmed map point.

The free BayernAtlas shows the Parzellarkarte, a reduced cadastral map without parcel numbers (LDBV FAQ). You can still search there: with Gemarkung plus numerator and denominator, the BayernAtlas search finds the parcel and sets a marker; only the numbers on the map are missing. The full ALKIS map with numbers is in the paid BayernAtlas-plus at €40.00 a month, cancellable monthly. A single uncertified cadastral map extract from GEODATENONLINE costs €20.00 per retrieval up to A3; it cannot be used for a building application.

When you need an official extract

A screenshot from the viewer carries no official seal. It is enough to name the right parcel and compare its outline with photos of the site. Where an office asks for proof, it is not enough.

For a building application, the site plan needs an extract from the cadastral map. In Bavaria it must show the building plot and the neighbouring plots within at least 50 m and be certified by the cadastral authority or obtained through the retrieval procedure under Art. 11(2) BayVermKatG (§ 7 BauVorlV). The LDBV's cadastral extract for building applications costs €48.00 with up to six map sheets up to A3; because it contains owner data, you have to show a legitimate interest.

For the purchase contract itself you usually need no extract of your own, because the notary checks the land register and the cadastre directly. It is different when only part of a plot is sold: the land registry may, as a rule, split off part of a plot only once that part has its own number in the cadastre (§ 2(3) GBO). How the division works is explained in Dividing a plot.

What the online map does not tell you

The map settles which parcel you are talking about. It does not say who owns it, which easement sits in section II, whether a Baulast burdens the plot, whether access is legally secured or whether a development plan applies. A line on the screen is not a boundary survey either: scale, old surveys and the overlay with aerial imagery can mislead. If a fence or garage stands on the line or there is a dispute with a neighbour, the question belongs with the surveying office or a publicly appointed surveyor; see Boundaries and land survey.

On the GrundCheck home page you search for the address and confirm the parcel on the map. The report then covers exactly that piece of land.