# The 34-day threshold, as a direct answer

HTML: https://teleworktracker.app/en/blog/34-day-telework-threshold-belgium-luxembourg.html
French: https://teleworktracker.app/blog/seuil-34-jours-teletravail-frontalier-luxembourg.md
Updated: 28 July 2026. Not tax advice.

## Someone asked: what is the 34-day threshold?

**Short answer.** For a Belgian cross-border worker employed in Luxembourg, **34 days per calendar year** is the commonly cited tolerance for days **worked outside Luxembourg**. Below it, the usual frame stays Luxembourg taxation of work-related pay. Beyond it, pay attributable to **all** those outside-Luxembourg days — not just the excess — can become taxable in the country of residence.

## Someone asked: why does it matter so much?

Because it is not "one extra day = a bit more tax". Crossing the threshold is a **regime switch**.

## Someone asked: is my ceiling always 34?

Not necessarily.

- **Proration** — part-time or mid-year start: your personal ceiling is not raw 34.
- **Kind of day** — telework, travel, training outside Luxembourg: it may count even if it does not feel like "working from home".
- **Proof** — a rough spreadsheet rarely holds when someone asks for the history.

## Someone asked: what should I actually track?

1. Your **personal ceiling** (not only generic 34).
2. Every outside-Luxembourg working day that may count — including a fraction of a day (= 1 day).
3. A warning **before** the edge.
4. An exportable history.

Telework Tracker does that tracking (ring, alerts, calendar, Pro PDF). It does not replace a tax adviser.

Next: [how to count](https://teleworktracker.app/en/blog/how-to-count-cross-border-telework-days.md) · [2026 circular](https://teleworktracker.app/en/blog/2026-circular-34-day-rule-luxembourg.md)