# 34 days and 50%: two different counters

HTML: https://teleworktracker.app/en/blog/social-security-telework-threshold-cross-border.html
French: https://teleworktracker.app/blog/securite-sociale-teletravail-frontalier-seuil-49.md
Not social-security or tax advice.

## Someone asked: does the 34-day threshold also apply to social security?

**Answer.** No. **34 days** = taxation of salary (Belgium–Luxembourg treaty). **Social security** = % of working time (EU law). A day is not a percentage.

| | Tax | Social |
| --- | --- | --- |
| Unit | Days | % of time |
| Limit | 34 / year (prorated) | < 25% default, or < 50% with framework agreement |
| Fraction of a day | = 1 day | actual time |
| Business travel | Often in the tax quota | Treated apart from social "telework" |
| Prior filing | None | Employer request + A1 |
| Exceeding | BE tax from 1st day outside LU | Affiliation switch + regularisation |

## Someone asked: how much telework to stay affiliated in Luxembourg?

**Answer.** Default EU rule: **25% or more** of activity in the residence state → that state's scheme (Belgian NSSO for a Belgian resident). Since **1 July 2023**, an EU **framework agreement** (23 EEA states + Switzerland, including BE and LU) allows **less than 50%** telework while keeping the employer's affiliation — **if** a request was filed and an **A1** issued. Without A1, 25% stays the reference.

Authorisation: **max 3 years**, renewable. Employer files with the institution of the establishment state (LU: CCSS).

## Common exclusions

More than two states; telework ≥ 50%; non-telework activity in the residence state (clients, sites); several employers in different states; self-employment on the side.

## Someone asked: is one day a week fine?

**Answer.** Not a single answer. One day/week ≈ 20% of time — often under 25% **and** under 34 days **if** those are the only outside-LU days. Training, travel, and half-days (which count as 1 tax day) can break one counter without breaking the other.

## Someone asked: will 34 increase?

Do not bank on it. Count the rule **in force**.