Short term rental in an apartment building: zoning, tenancy law and buyer guarantees before acquisition

Short-term rental is an income lever in an apartment building stock and, at the same time, a risk field. Whether it is admissible in a specific property depends on zoning under the spatial planning law, on the building law use and on the tenancy law framework. Anyone acquiring an apartment building with such a use has to check the legal basis early on so that a yield promised in the sales brochure actually holds up.

This article sets out the review axes. It covers the zoning position under the Salzburg Spatial Planning Act 2009, in particular section 31b in the version in force since 1 August 2025, the limits of the Austrian Rent Act (MRG) for short-term rental, building law admissibility and the clauses required in the sale contract and data room.

Why short-term rental is its own review layer

Short-term rental is often presented as a yield opportunity. For the apartment building stock it is a separate review layer. It links zoning, building law, tenancy law and tax law in a way that no single line in the sales brochure can capture. Without its own review layer, income promises end up without foundation.

In practice a separation by type of use helps. A commercial accommodation with reception, cleaning and breakfast is subject to different rules than a holiday flat marketed through platforms without services. Occasional short-term rental alongside a long-term lease has its own evaluation again. The topic page apartment building purchase covers the base questions of an acquisition.

For the buyer, careful research prevents disappointment. For the seller, an honest presentation avoids later assurance issues. The apartment building risk check helps with the initial framing.

Salzburg Spatial Planning Act 2009: diversion of housing and secondary residences

The Salzburg Spatial Planning Act 2009 separates secondary residence use from tourist accommodation. Section 31 governs spatial planning restrictions on secondary residences. Section 31b deals with the diversion of existing housing: since 1 August 2025, using an existing flat for tourist accommodation is in principle a diversion requiring a permit. No permit is needed only where one of the statutory exceptions in section 31b(2) applies.

The specific flat, its zoning, the actual use and any exception or permit therefore have to be reviewed separately. Residential zoning alone does not establish that tourist accommodation is allowed. Conversely, a spatial planning permit does not replace the building and trade law requirements of an accommodation business.

For the purchase the decisive point is whether the actual use is consistent with the zoning position. If the short-term rental takes place without a zoning basis, the authority can order a stop or a return to the zoning-compliant use. The article on monument and old town protection in Salzburg maps further municipality-specific requirements.

MRG scope and short-term rental

Section 1 MRG defines the scope of the Austrian Rent Act. Section 1(2)(1) excludes premises let in the operation of an accommodation business. The actual operating concept, including the ancillary services offered, is decisive; a short contract term alone does not turn a residential letting into an accommodation business. Section 1(2)(4) separately excludes flats or rooms rented by the tenant solely as a secondary residence for recreation or leisure.

Intermediate forms require careful review. Recurring short residential lettings without accommodation services can fall within the MRG if no other exception applies. Which rent, term, termination or indexation rules then apply also depends on full or partial application in the particular building. The topic page on rent rolls and lease agreements maps the tenancy documentation.

For the sale preparation the actual use practice of recent years is important. It provides the basis for the classification as an accommodation business or as an MRG-covered rental. The article on fixed-term leases shows how short lease terms flow into income planning.

Building law and plant licence: limits of change of use

A unit permitted for residential use is factually operated as an accommodation business through recurring short-term rental with services. This can trigger building and trade law requirements, in particular for fire protection, escape routes, reception and plant licence. Without this basis a supervisory authority can order the stop of the use and require modifications.

In the stock a per-unit review is advisable. Not every short-term rental necessarily triggers a change of use; the decisive factor is the overall picture, in particular the frequency, the duration and the services. The topic page on due diligence and the data room maps the typical permit evidence.

For the sale preparation the building file and the permit situation for recent alterations should be reconciled with the current use. The topic page on old buildings, renovation and maintenance shows the construction review depth.

Sale contract clauses and buyer guarantees

The sale contract should map three layers precisely. First, assurances on the zoning admissibility of the use, on existing decisions and on open proceedings. Second, assurances on the building and trade law admissibility and on the plant licence. Third, the treatment of income promises linked to short-term rental.

On the income side, flat income guarantees are of limited value. More precise are undertakings on actual rental periods, on net revenue in defined periods and on the continuation of platform contracts. The topic page on an apartment building sale maps safeguards for risks that are not readily quantified.

For handover and data room, platform accounts, running bookings and open advance payments should be transferred in a structured way. The data room completeness check helps organise the records. The topic page handover and effective date shows how open items are treated at the effective date.

Buyer risk profile and time buffer

For a buyer who wants to continue the existing short-term rental, a realistic risk profile is advisable. It covers zoning admissibility, building and trade law basis, actual demand in the location and the possibility of a regulatory tightening at municipality level. A durable income model absorbs these axes with a base case and sensitivities.

A spatial planning permit or building law change should be completed before the intended operating start. A buyer who enters unresolved proceedings without a buffer risks rental losses. For the initial framing of the time frame the apartment building risk check can help.

For a change of use from long-term to short-term rental, stricter conditions apply. Existing tenants are protected by the MRG; a change of use usually requires the unit to be free and the zoning admissibility must be evidenced.

Practical process and next steps

The starting point is a stock take of zoning, building and trade law basis and actual use. The MRG layer and the tax layer are added. For the data room, platform accounts, booking administration and accounting are structured.

For a sale, assurances, transition clauses and handover logic are inserted into the sale contract. For an acquisition, a list of open questions is drawn up and its answers are sought before the price commitment. BRANDAUER Rechtsanwälte supports owners, sellers and buyers with an apartment building on short-term rental, zoning and tenancy law admissibility.