There are activities which are exempt (e.g. provision of services abroad) and those which are exempt from VAT (e.g. medical or cultural services). In addition, a company is only liable for VAT if its turnover in Switzerland exceeds CHF 100,000. You must therefore register with the Swiss Federal Tax Administration (FTA) and apply for a VAT number when you set up your company.
However, it is also possible that you voluntarily subject yourself to VAT (if your turnover is less than CHF 100,000). If your company expands its business and therefore expects to exceed this threshold, it will also be subject to VAT and must register with the FTA.
Therefore, an extrapolation must be made after three months. If the extrapolated turnover exceeds the threshold of CHF 100,000, the company has to register with the FTA. However, if the threshold value is only exceeded some time after the company is founded, your company must register with the FTA on 1 January of the following year.