Swiss HR consultancy Service-Juridique published an in-depth briefing on 18 September that recaps and clarifies the tax treatment of cross-border telework under the 2025 additional agreement to the Switzerland-France double-tax treaty. Effective 1 January 2026, French residents employed by Swiss companies may work remotely from France for up to 40 % of annual working time (plus ten mission days) without shifting their tax liability. Beyond that threshold, income is taxable in France and the employee risks losing cross-border commuter status. Employers must begin issuing annual certificates detailing each affected worker’s telework percentage by January 2027; cantonal tax offices will forward the data to French authorities by 30 November of the following year. For mobility managers the paper provides practical guidance on counting mission days, prorating limits for part-time staff and avoiding inadvertent breaches that could trigger dual withholding. It also reminds Swiss employers that collecting French tax on France-sourced work is illegal without authorisation – a point sometimes misunderstood in payroll circles. The clarification comes as hybrid work settles into a new normal along the CHF 70-billion Lake Geneva economic corridor, where roughly 95,000 French residents commute daily. Companies with high telework uptake should review employment contracts and time-tracking systems to ensure accurate reporting; failure to supply data could expose firms to Swiss administrative fines and French tax queries. While the article is aimed at legal practitioners, its practical examples make it a valuable resource for HR, payroll and mobility teams overseeing Franco-Swiss work arrangements.
Source: Service-Juridique
