Quick calculator guide for foreign buyers: estimating retroactive Grundsteuer B bills (Sept–Dec 2026)

What the notice shows (and the basic formula)

Municipal Grundsteuer (typical for built property: Grundsteuer B) is set in two stages. First the Finanzamt issues a Steuermessbetrag (a Euro amount), then the municipality applies its Hebesatz (a percentage) to arrive at the annual Grundsteuer. In short: Steuermessbetrag × Hebesatz = annual Grundsteuer. The Steuermessbetrag is fixed by the Steuermessbescheid from the Finanzamt; the municipality’s Grundsteuerbescheid shows the final payable amount. ([lstn.niedersachsen.de](https://lstn.niedersachsen.de/steuer/grundsteuer/grundsteuer-b-grundvermogen-209755.html?utm_source=openai))

On a modern Grundsteuerbescheid you should find at least: the Steuermessbetrag (in €), the Hebesatz (in % or v. H.), the calendar year(s) covered, and a Rechtsbehelfsbelehrung (information about the deadline to object). If a notice covers multiple years or corrects a previous assessment it will list the effective period and any arrears or credits. Read the top‑left block of the notice for those items first. ([hebesatzatlas.de](https://hebesatzatlas.de/lexikon/grundsteuermessbescheid/?utm_source=openai))

Step‑by‑step calculator: how to compute a retroactive bill for Sept–Dec 2026

1) Find the numbers. From the Grundsteuerbescheid note: (a) Steuermessbetrag (EUR per year), (b) Hebesatz (e.g. 350 % shown as 350 v. H.), and (c) the year(s) the bill covers. If the Finanzamt issued a separate Steuermessbescheid, use the Messbetrag there. ([finanzamt.hessen.de](https://finanzamt.hessen.de/grundsteuer/faq-grundsteuer/allgemeines?utm_source=openai))

2) Annual and monthly amounts. Compute annual Grundsteuer = Steuermessbetrag × Hebesatz (express Hebesatz as a decimal, e.g. 350 % = 3,50). Monthly amount = annual amount ÷ 12. Example (illustrative): Steuermessbetrag €200 × Hebesatz 350 % = €700 annual → €58,33 per month. (This is a worked example, not a quoted municipal rate.)

3) Identify the liable months. The tax authority’s notice will state which months/years it demands. If the demand covers months you owned the property before completion/possession, compute the pro‑rata difference for those months. Use exact days if the notice uses dates; otherwise months are commonly treated pro rata by calendar month.

4) Compare to payments already made. Subtract any advance payments or amounts the seller already paid for those months. The result is the remaining net claim. If the municipality lists an interest charge or late‑payment surcharge, include that — it will appear as a separate line on the notice.

5) Example summary. Using the illustration above: municipality demands recalculation for Jan–Dec 2026 with a new annual amount €700. If the seller already paid €300 for Jan–Aug, the buyer would be liable for Sept–Dec (4 months): 4 × €58,33 = €233,32. Net additional payment = €233,32 (unless the contract allocated a different split).

Legal deadlines and who is formally liable

If you want to challenge a Grundsteuer‑Steuermess‑ or Grundsteuerbescheid you must respect the statutory objection (Einspruch) deadline. Under the Abgabenordnung the Einspruch against a tax assessment is generally due within one month after the notice is served (Beginn der Einspruchsfrist depends on the Belehrung in the notice). File it in writing or electronically with the Finanzamt named in the notice. ([gesetze-im-internet.juris.de](https://www.gesetze-im-internet.juris.de/ao_1977/BJNR006130976.html?utm_source=openai))

Formally the tax authority regards the Grundstückseigentümer as tax debtor; a change of ownership often takes effect for taxation only at 1 January of the following year, and municipalities will still pursue the legal taxpayer named in their records if payments are missed. Private purchase contracts almost always allocate the year’s tax between seller and buyer (typically pro rata at possession), but those private arrangements do not change who the Finanzamt will pursue if the bill is unpaid. Read the Bescheid’s addressed name and dates carefully and check your purchase contract wording on “Lastenübergang” or “Übergabestichtag”. ([berlin.de](https://www.berlin.de/sen/finanzen/steuern/informationen-fuer-steuerzahler-/artikel.1049925.php?utm_source=openai))

Deciding whether to raise purchase escrow (practical checklist)

Use the notice and your contract to estimate your net exposure for Sept–Dec 2026 (steps above). Then run these checks before asking the notary to increase escrow:

• Confirm who the Bescheid names and for which dates. If the notice names the seller and the tax period falls before possession, a seller‑side settlement is usual; but municipalities sometimes seek unpaid sums from the last registered owner if a bank chargeback or insolvency occurred. ([hansestadt-uelzen.de](https://www.hansestadt-uelzen.de/home/buerger-service/finanzen-abgaben/grundsteuer_alt/verkauf-eines-grundstueckes.aspx?utm_source=openai))

• Check the Einspruch deadline. If the figures look wrong (wrong floor area, wrong Bodenrichtwert used, wrong ownership fractions) file an Einspruch within one month and instruct the seller to cooperate in evidence exchange. ([gesetze-im-internet.juris.de](https://www.gesetze-im-internet.juris.de/ao_1977/BJNR006130976.html?utm_source=openai))

• If you cannot resolve allocation with the seller, consider asking the notary for a temporary escrow holdback (Treuhand) large enough to cover the net claim plus a margin for interest/fees for the 4 months Sept–Dec. Exact wording and permitted amounts are a matter for your notary; ask them to draft a conditional release tied to final settlement of the municipal claim or to written seller indemnity. Do not rely solely on verbal promises. ([kanzlei-arnimbuck.de](https://kanzlei-arnimbuck.de/wp-content/uploads/2024/10/Der-Immobilienkaufvertrag.pdf?utm_source=openai))

Important: this article is informational. For contract drafting, escrow sizing or a formal Einspruch consult a German notary and a Steuerberater — they must review the specific Bescheid and your purchase deed before you decide on escrow changes.