Written form in German commercial leases: What applies since the text-form reform

Key takeaways

• Since 1 January 2025, commercial leases with a term of more than one year only require text form (email, PDF) instead of strict written form with original signatures. ^2,6
• For legacy leases, the old written-form law continued to apply transitionally – but only “up to and including 1 January 2026”. Today, the text-form regime applies to all commercial leases. ⁵
• The legal consequence of a formal defect remains severe: the lease is deemed concluded for an indefinite period and can be terminated with ordinary notice – despite the agreed fixed term. ^1,2,4
• Written-form cure clauses offer no protection: the Federal Court of Justice declared them invalid in 2017. ⁷

The old written-form trap: A missing signature could unravel a lease

For decades, German commercial tenancy law followed a simple but treacherous rule: a lease concluded for longer than one year required written form – a single deed with original signatures of both parties (§ 550 BGB). If the form was missed, the contract was not void. The consequence was subtler and often worse for tenants planning long-term: the lease was deemed concluded “for an indefinite period” – and could therefore be terminated with ordinary notice, as if the agreed term had never existed. ¹

The trap rarely snapped shut on the original lease. It almost always struck through amendments: the rent adjustment agreed verbally, the space extension “confirmed” by a plain email, the parking space that never made it into a signed deed. Any essential agreement outside written form could render the entire lease terminable. ^1,9

What “terminable with ordinary notice” means in practice

For business premises, ordinary termination is permitted at the latest on the third working day of a calendar quarter, effective at the end of the next calendar quarter (§ 580a Abs. 2 BGB). An example: if notice is received by the third working day of January, the tenancy ends on 30 June – depending on timing, roughly six to nine months remain. Termination is possible at the earliest at the end of one year after handover of the premises. ^4,1

Who the trap hits – and who it helps

For tenants with substantial location investments – shopfitting, restaurant build-outs, practice equipment – premature terminability is an existential threat: the investment is calculated over ten years, but after a formal defect the landlord can terminate early, for instance to re-let at a higher rent. This becomes particularly relevant when the property is sold: the buyer steps into the lease, and it was precisely the buyer that § 550 BGB was historically designed to protect – they should be able to rely on the documented terms. ^1,7

But the trap cuts both ways: tenants could also use a formal defect to escape a burdensome long-term lease – a legal exit lever, limited only by good faith in the individual case (more on this below). ⁷

BGH 2017: The end of cure clauses

To defuse the trap, contract drafters spent years writing so-called written-form cure clauses into commercial leases: both parties undertake to do whatever is needed to satisfy written form on request – and not to terminate for a formal defect in the meantime.

The second half of the judgment matters just as much: invoking the formal defect can be contrary to good faith in the individual case (§ 242 BGB) – for instance where a party uses an amendment that benefits only itself as the occasion to walk away from the entire lease. The “exit lever” is no free pass. ⁷

The reform: Text form instead of written form since 1 January 2025

With the Fourth Bureaucracy Relief Act (BEG IV) of 23 Oct 2024, the legislator significantly lowered the formal hurdle for commercial leases. Since 1 January 2025, § 578 Abs. 1 Satz 2 BGB provides that § 550 applies “with the proviso that a lease concluded for longer than one year not in text form is deemed concluded for an indefinite period”. Via § 578 Abs. 2 BGB this covers all leases of premises that are not residential – offices, shops, warehouses, practices. ^2,6

What text form means

Text form (§ 126b BGB) now only requires: a readable declaration that names the person making it, provided on a durable medium. An email, a PDF scan or a digitally exchanged contract document satisfies this – original signatures and the single paper deed are no longer required. A handshake or a phone call, however, remain form-free – and therefore risky. ³

Transitional law: What applies to legacy leases today?

For leases concluded before 1 January 2025, the old written-form law continued to apply transitionally – in the words of the statute “up to and including 1 January 2026” (Art. 229 § 70 Abs. 1 EGBGB). If a legacy lease was amended on or after 01.01.2025, the new law applied from the amendment onwards. ⁵

As of today (July 2026), the transition phase is over: the text-form regime applies to all commercial leases – including legacy leases. Only residential leases still follow the written form of § 550 BGB; farm leases had a longer transition period (up to and including 01.07.2026). ^5,2,8

Fact check: Four myths examined

Myth 1: “The cure clause in our lease protects us against termination for a formal defect.”

False. Written-form cure clauses have been invalid since the Federal Court of Justice judgment of 27 Sept 2017 – they do not prevent any party from terminating for a formal defect. Only clean documentation itself offers protection; in individual cases a termination may fail on grounds of good faith. ⁷

Myth 2: “Amendments by email are the classic written-form trap – risky!”

Outdated. Since 1 January 2025 (new leases) and since early 2026 (all leases), text form suffices: an email amendment that names the person making the declaration satisfies the form. Many warnings still found online date from before the reform and are obsolete. What remains decisive: the agreement must actually be documented in text form – a purely verbal amendment still violates the form requirement. ^2,3,5,6

Myth 3: “Text form now also applies to residential leases.”

False. § 550 BGB itself is unchanged and still requires written form for residential leases. The text-form proviso appears only in § 578 BGB (land and premises that are not residential) and in farm-lease law. ^1,2,6

Myth 4: “Since the reform there is no formality trap anymore.”

Only partly true. The hurdle is lower, but it still exists: leases or essential amendments outside any text form – handshake, phone call, verbal rent adjustment – still lead to terminability for terms of more than one year. It is not yet settled by the highest courts how strictly the case law on essential contract terms, developed for written form, will be applied to scattered email threads – the conservative approach remains: coherent amendment documents instead of loose email trails. ^2,3,9

Practical checklist for commercial tenants

1. Document the essentials: parties, property and floor area, rent, service charges, term and options must be fully documented in text form – at conclusion and at every amendment. ^2,3
2. Confirm verbal commitments immediately: “As discussed, we agree …” by email, with confirmation from the other side – and archive as PDF. ^3,9
3. Review your existing lease: are there amendments or commitments that were never documented? Then a terminability risk remains even under the new law – document them in text form now. ^2,5
4. Watch your own form clauses: the parties may contractually agree on stricter forms (such as elective written form) – then your own contract governs. ⁹
5. Keep the exit lever in mind: if you want out of a long-term lease, your own records will show whether essential agreements are documented in no form at all. Whether this actually gives rise to a termination right belongs in the hands of legal counsel – the limit is bad faith in the individual case. ^7,4

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