Swiss {ai} WeeksA guide by the organisers of an official Swiss {ai} Weeks event · Lugano, 28 October 2026 · Event page
The Effective Prompting GuideSwiss {ai} Weeks · Lugano 2026

The cases of the evening ›

Tax case

Danilo Ceglie: mixed-use expenses of a GmbH (Sagl) in Ticino.

Danilo Ceglie

Danilo Ceglie

Fiduciary and accountant, Fiduciaria Vella

BEFORE · the non-expert's prompt

“I have a GmbH (Sagl) in Ticino. Tell me all the expenses I can write off to pay less tax this year, including my car, phone and dinners with friends and clients.”

What was missingThe distinction between company expenses and private expenses. «Write off» pushes the AI towards Italian percentages and rules.
AFTER · the professional's prompt

Act as my assistant in preparing materials for a client. I look after a GmbH (Sagl) based in Ticino, registered for VAT, with a managing partner (socio gerente) who also uses a company car for private purposes. Prepare a draft information note for the client on the deductibility of mixed-use expenses (car, phone, entertainment expenses (spese di rappresentanza)).

  1. Do not use promises of savings or lists of "everything you can write off". The guiding criterion is that the expense must be justified by business use.
  2. For each item, separate the business share from the private share. Explain the risk of a tax adjustment (ripresa fiscale) as a hidden profit distribution (distribuzione dissimulata di utili) and what documentation is needed (receipts, participants, purpose).
  3. Indicate where the VAT treatment (input tax deduction) and the direct tax treatment may differ, flagging the points to check against the current practice of the Swiss Federal Tax Administration (FTA) and the cantonal tax authority.

Do not quote rates or flat-rate amounts unless you are sure they are up to date: leave a placeholder [to be verified]. Use clear language for a non-technical business owner.