In one sentence
Almost every deadline under German law follows three provisions — Section 187 BGB (start), Section 188 BGB (end), Section 193 BGB (weekends and public holidays) — and most missed deadlines don't happen because someone dawdled, but because of calculation errors at exactly these three points.
Rule 1: The day of the triggering event doesn't count (Section 187(1) BGB)
If a letter reaches you on a Monday and a two-week deadline runs from the date of receipt, the count only starts on Tuesday. The triggering day itself — receipt, service, becoming aware of it — is excluded. This is by far the most common source of error, because intuitively it feels like the day the letter landed in your mailbox "counts".
Important here: what matters is receipt, not the date printed at the top of the letter. A letter dated the 1st that lands in your mailbox on the 5th starts the deadline running on the 5th. So always note down when a letter actually arrived — if in doubt, with a photo of the envelope and the postmark.
Rule 2: Section 188 BGB determines the end
A deadline measured in weeks or months ends at the close of the day whose name or number corresponds to the triggering day. In concrete terms: receipt on Monday the 14th, a two-week deadline — the deadline ends on Monday the 28th at midnight (24:00). Not the Sunday before, and not "two weeks plus the partial first day".
And: the end of a deadline means the close of the entire day. A deadline ending on the 28th is met by a declaration that's received at 23:59 on the 28th — though you'd be wise not to cut it that close, because a submission at that hour is exactly when the dispute over the actual time of receipt tends to start.
Rule 3: Saturday, Sunday, public holiday — Section 193 BGB shifts the deadline to the next business day
If the end of a deadline falls on a Saturday, Sunday, or a state-recognised public holiday at the place where the declaration is to be made, the next business day takes its place instead. Two pitfalls hide in this unassuming sentence:
- Public holidays are a matter for each federal state. Corpus Christi (Fronleichnam) is a public holiday in Bavaria, but not in Hamburg. What matters is the place where the declaration is to be made or the performance is to take place — not where you live.
- The shift doesn't apply to everything. Section 193 BGB shifts the end of a deadline for declarations of intent and for performance obligations. It does not, for example, extend the duration of a tenancy or other types of time periods — if in doubt, this exact question belongs in expert hands.
For court deadlines, Section 222 ZPO refers back to these same BGB rules — so the underlying system stays the same, whether you're responding to a lawyer's letter or to a court order.
The classic mistakes at a glance
- Using the date on the letter instead of the date of receipt as the start of the deadline — the deadline almost always starts with receipt.
- Counting the triggering day itself — Section 187(1) BGB says no.
- Confusing business days with calendar days — Saturday is a business day, even though it doesn't feel like one.
- Applying the public holiday of the wrong federal state.
- Leaving it until the last day — anyone who falls ill or gets stuck in traffic right at the deadline has no buffer left.
How SmartLegalPro handles deadlines
Deadlines are too important to us for pure AI estimates. When the document analysis detects a deadline in your document, a second check runs — and the actual calculation is handled by deterministic code following Sections 187, 188, and 193 BGB, which also knows the movable public holidays for each federal state. In your account's deadline centre, you'll find every detected deadline as a register, plus a deadline calculator for working things out yourself. What the software doesn't replace: the legal assessment of whether a deadline genuinely applies in your specific case and what missing it would mean — if in doubt, the one-click handover connects you with a lawyer.
This article provides general orientation and doesn't replace legal advice in an individual case.
