Gewerbesteuer is the municipal tax on business income, and a GmbH is subject to it by its legal form — even if it does nothing but let a supermarket. Its rental income is fully relieved only through the extended reduction; without it, trade tax typically takes 10.5–17.5% of trade income on top of corporate tax.
• The multiplier of the municipality entitled to levy the tax (§ 4(1) GewStG), and any announced change.
• Whether the extended reduction applies to the specific lease, confirmed by a tax adviser before signing.
• Where it does not apply, the interest add-back on financing costs above €200,000 a year.
• For a GmbH bought as a share deal, its trade-tax assessments and any open tax audit.