
Tax advisory for architecture firms in Sulgen explained simply
Whether you run a Sàrl, an SA or a sole proprietorship in Sulgen, tax advisory eventually lands on your desk. Here are the practical reference points — legal basis, deadlines and common pitfalls — to decide with a clear head.
The Swiss legal frame for tax advisory
Responsibility for the books is personal: in an SA, organising the accounting is one of the board's non-transferable duties (art. 716a CO); in a Sàrl, the managing directors carry the same duty. Outsourcing the execution never transfers that underlying responsibility, including for a company based in Sulgen.
For tax advisory, the classic early mistake remains mixing private and business: a dedicated bank account and documented private withdrawals eliminate half the discussions with the tax office.
Swiss VAT: rates, threshold and filings
Since 1 January 2024, Swiss VAT rates are 8.1% (standard), 2.6% (reduced — food, books, medicines) and 3.8% (accommodation). Registration becomes mandatory from CHF 100,000 of worldwide annual turnover. For tax advisory, step one is therefore checking the threshold and choosing the right reporting method.
A business in Sulgen that crosses the threshold mid-year must register without delay: retroactive registration with interest always costs more than signing up on time.
Year-end closing: how the mechanics work
Depreciation follows rates accepted by tax practice (property, machinery, IT): staying within those ranges avoids reassessments. Exceeding them is justified — and documented, in Sulgen as anywhere.
The notes complete the figures: valuation principles, liabilities towards pension institutions, contingent liabilities, or the number of full-time positions. Careful notes reduce questions from the auditor and the banks.

Outsource tax advisory or keep it in-house?
The Swiss fiduciary market is dense and governed by professional practice: industry standards, business secrecy, civil liability. Compare offers on three concrete criteria — exact scope (data entry? closing? payroll? VAT?), a named contact person, and the tools used. It prevents year-end misunderstandings.
In Sulgen, as everywhere, the right collaboration rhythm follows the activity: monthly for payroll and data entry, quarterly for VAT, yearly for the closing and tax advice.
Sulgen: what changes, what does not
Sole proprietorship, Sàrl or SA in Sulgen: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Thurgau.
Federal deadlines do not move in Sulgen: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 8583 changes nothing about those rules, only the sender's address.
Frequently asked questions
Can tax advisory be automated with AI?
Largely, yes: automatic document reading, posting suggestions, bank reconciliation via QR references and VAT exports. Human approval remains essential — AI prepares, the professional checks. That is exactly how MyFiducia.ai approaches tax advisory.
Do you need a fiduciary for tax advisory, or can you do it yourself?
Both are defensible. Below CHF 500,000 of revenue, a sole proprietorship may keep simplified accounts itself. As soon as payroll, VAT and a closing with tax stakes are involved, professional support prevents mistakes that cost more than the fees. With a shared platform, the fiduciary does not even need to be in Sulgen.
How long must records related to tax advisory be kept?
Ten years from the end of the financial year concerned (art. 958f CO). Electronic retention is permitted if the integrity and readability of the records are guaranteed — a serious digital archive validly replaces paper binders. A business in Sulgen can therefore archive fully digitally.
What are the legal obligations for tax advisory in Switzerland?
The foundation is the Code of Obligations: proper bookkeeping (art. 957a CO), annual accounts (balance sheet, income statement, notes) and 10-year retention of books and records (art. 958f CO). VAT applies from CHF 100,000 of turnover, and social insurance settlements from the first employee. Nothing is different in Sulgen: federal law applies.
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MyFiducia.ai automates tax advisory for businesses in Sulgen: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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