Cross-border telework in 2026: what Swiss employers need to do

Income tax and social insurance: two separate questions

Imagine Clara, who lives in Annemasse and works for a small company in Geneva. She would like to spend part of the week working from home. Her employer needs to answer two questions: where will her salary be taxed, and where should social insurance contributions be paid?

Both answers depend on where Clara works, but the rules are different. This is why official information refers to several percentage thresholds.

In practice, Clara could qualify to remain in the Swiss social insurance system while part of her salary becomes taxable in France. An agreement covering social insurance therefore does not settle the tax question.

For the rest of this article, we use the example of a private-sector employee who lives in France and works in Geneva. Tax treatment differs in some other cantons. In Vaud, for example, an employee who meets the conditions of the 1983 frontier-worker agreement is generally taxed in France. The explanations about Geneva payroll tax deductions cannot simply be applied to that employee.

Income tax: what does the 40% limit mean?

For our Geneva employee, the starting point is straightforward: her salary can remain fully taxable in Switzerland if she works remotely from France for no more than 40% of her annual working time, subject to the business-trip rules explained below. The employer then continues to deduct Swiss withholding tax from the whole salary.

Two days a week is a reference point, not an automatic entitlement

In a five-day working week with equal-length days, two days represent 40%. This explains the common statement that a cross-border employee can work from home two days a week.

However, the tax limit is assessed over the year. Part-time schedules also matter: for someone working four days a week, two days at home already represent 50% of their working time.

A simple calculation

Suppose Clara actually worked 220 days during the year, including 77 days from her home in France, with no business trips abroad. Her telework percentage is:

77 days ÷ 220 days × 100 = 35%.

She stays below the 40% limit. On the same 220-day basis, the maximum would be 88 days. This number depends on the working time used in the calculation; it is not a fixed annual allowance for every employee.

The Geneva cantonal tax authority, known as AFC Genève, allows records in days, half-days or hours, provided the employer uses a consistent method for all staff. It also accepts a simplified basis of 240 days a year for full-time work. The examples in this article instead use 220 days actually worked. Annual leave and sick leave are not telework days. For part-time employment or a contract covering only part of the year, the calculation must reflect the relevant employment period and workload.

What happens if telework exceeds 40%?

Now suppose Clara works from home for 99 out of 220 days, or 45%. In this case, the salary attributable to all 99 days worked in France becomes taxable in France. The change applies to every telework day in the year, not just the 11 days above the 88-day limit.

The salary attributable to work carried out in Switzerland remains taxable in Switzerland. The employer must have the salary allocation between the countries and the payroll tax deductions checked. French procedures also need to be considered: you should not simply add a French tax deduction to the payslip without reviewing the applicable process.

Our article on Geneva withholding tax explains how tax is deducted from salary.

Business trips: how does the 10-day allowance work?

A day visiting a client in Lyon or attending training in Paris is not a homeworking day. It is a temporary assignment abroad. These days nevertheless affect the tax calculation.

The rules provide an allowance: up to 10 days of assignments in France or another country can remain taxable in Switzerland, provided they fit within the overall 40% limit. These 10 days are included in the 40%; they are not added on top. The annual 10-day allowance is reduced proportionately for part-time work or employment lasting less than a year, with the result rounded up to a whole day.

On a basis of 220 working days, 80 days at home plus 6 assignment days total 86 days, or 39.09%. Both limits are met: less than 40% in total and fewer than 10 assignment days.

With 86 days at home and 6 assignment days, the result changes. The 88-day maximum leaves room for only 2 assignment days. Under Geneva's rules, the other 4 assignment days are taxable in France, while the homeworking days remain taxable in Switzerland.

Similarly, exceeding 10 assignment days does not automatically make all homeworking days taxable in France. This is why the two categories should be recorded separately. The Geneva tax authority's official examples explain the different cases in French.

Social insurance: what is an A1 certificate for?

Now let us turn to the second question: social insurance contributions. When someone regularly works in two countries, their applicable social security system must be determined. The A1 certificate confirms which country's social security legislation applies. It can therefore demonstrate that the employee remains covered by the Swiss system.

Why the 25% threshold already matters

Take the straightforward case of an employee covered by the Switzerland–EU coordination rules, with one Swiss employer, who works only in Switzerland and from their home in France. Under the ordinary rules, the employee can remain insured in Switzerland if homeworking in France represents less than 25% of their activity.

From 25%, the ordinary rules generally lead to coverage under the French system. However, a framework agreement signed by both France and Switzerland allows Swiss coverage to continue when telework remains below 50% and the other conditions are met. The employer must apply for this arrangement.

A regular schedule of two homeworking days out of five represents 40%. It may satisfy the tax rules, but it exceeds the 25% social insurance threshold. The application to remain in the Swiss system must therefore be dealt with too. Meeting the 40% tax limit alone is not enough.

How do you apply?

The Swiss employer applies for an A1 certificate through its AHV/AVS compensation office, using ALPS, the online platform for these requests. Under the framework agreement, a certificate can cover up to three years and can be renewed.

It is best to apply before the proposed working arrangement begins. For applications submitted since July 2024, backdating under this agreement is limited to three months. Waiting until the end of the year could therefore leave an earlier period outside the certificate's coverage.

Situations that need a separate check

The framework agreement does not cover every employee. Regular client visits in France, a separate self-employed activity, another employer based in an EU country or regular work in a third country can change the assessment. Nationality also matters: the coordination rules discussed here cover Swiss, EU or EFTA nationals within their respective scope.

At 50% telework or more, this framework agreement no longer provides a basis for maintaining Swiss coverage. The competent institution must examine the applicable rules. Even below 25%, the ordinary procedures for determining the applicable legislation and obtaining an A1 certificate still apply. Being below that threshold does not mean there are no formalities.

What must employers record and report in 2026?

In Geneva, employers must track telework and assignment days for employees living in France from 1 January 2026. The 2026 records will be used for the first reporting deadline in January 2027. This makes it important to keep records throughout the year.

A practical record should answer the following questions for each employee:

For Geneva reporting, the employer submits a percentage, rather than simply a number of days. It is entered on the annual withholding-tax summary or sent through ELM or ISeL, the electronic reporting channels. There is no requirement to enter it on the Swiss salary certificate.

If an employee works for several businesses, each employer reports the percentage relating to the work performed for that business. When someone leaves during the year, the employer must provide the certificate for employment lasting less than one year if the employee requests it. This lets the new employer see the days already worked from home or on assignments. That certificate is given to the employee, not sent to the Geneva tax authority.

How should you organise telework in your business?

The arrangement is easier for both employer and employee when everyone knows from the start what is allowed and how it will be recorded. A practical approach is to:

1. Check the employee's circumstances. Where do they live? Do they have another job or a self-employed activity? Do they travel regularly? These answers help identify the applicable rules.
2. Put the arrangement in writing. A contract addendum or telework policy should specify authorised locations, the planned schedule and how to request an extra homeworking day.
3. Resolve the social insurance position. Contact your compensation office about the applicable procedure and, where necessary, apply to maintain Swiss coverage under the framework agreement.
4. Keep a simple, regular record. The employee enters their work locations and business trips; a designated person in the company checks the information each month.
5. Plan ahead for year-end. Compare days already worked and days still planned with the applicable limit. This gives you time to adjust the schedule before a threshold is exceeded.

Employees should also notify you before working from another country. A week of remote work from a holiday destination abroad needs to be checked in advance, even when the annual allowance appears sufficient.

Tax and social insurance records do not replace the other arrangements you need: working hours, equipment, confidentiality and access to company data. For certain roles, particularly where an employee regularly negotiates or concludes contracts from abroad, you should also assess the risk of a permanent establishment. This means the employee's activities could create a taxable business presence for the company in that country. The assessment depends on the facts.

If you are setting up your first HR processes, our article on hiring your first employee in Switzerland explains the wider steps to take.

A clear arrangement makes cross-border telework easier

Cross-border telework is easier to manage when everyone understands the rules. Employees know which days and locations are authorised; employers have the information needed for payroll and reporting.

Start by checking the tax and social insurance position, put the agreed arrangement in writing and track days month by month. These steps help you offer flexibility while keeping your employer obligations under control.

Related articles

• Geneva withholding tax: the rules for 2026
• Swiss work permits: what foreign employees need to know
• Hiring your first employee in Switzerland

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