This page inFRDEENAR

Smiling team looking at a laptop

Tax advisory online in Lengnau (AG): the practical guide

Whether you run a Sàrl, an SA or a sole proprietorship in Lengnau (AG), 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

For an owner in Lengnau (AG), the question is never “do we need accounts?” but “at what level of detail?”. The CO sets the floor; the bank, the tax office and the shareholders set the rest.

Also worth knowing: accounts may be drawn up in the currency most relevant to the business; if that is not the franc, values must additionally be stated in CHF (art. 958d para. 3 CO). Internationally active companies gain books that match their economic reality.

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 Lengnau (AG) as anywhere.

A well-ordered closing file speeds everything up: bank statements at the closing date, a signed inventory, final AHV/LPP/accident settlements, new or amended contracts, and support for the accruals. Tax advisory in Lengnau (AG) then finishes in days, not weeks.

Outsource tax advisory or keep it in-house?

A fiduciary's cost depends first on the quality of the data received: digitised, filed, reconciled documents are processed fast; a box of loose receipts is billed by the hour. Improving the internal preparation of tax advisory lowers fees more surely than any negotiation.

Changing fiduciary is not a drama: the accounting data belongs to the company, and a clean export (entries, chart of accounts, linked documents) allows a transition at year-end. A provider who locks in a client's data says a lot about how it works.

Collaborative desk with laptops and documents, top view

A Swiss SME's accounting calendar

An accounting calendar only lives if it is shared: owner, in-house bookkeeper and fiduciary must see the same deadlines and the same status — the rule holds for every SME in Lengnau (AG).

For tax advisory, two dates lock themselves in every year: the January salary declaration and the general meeting within six months — everything else is planned around them.

Lengnau (AG): what changes, what does not

Sole proprietorship, Sàrl or SA in Lengnau (AG): the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Aargau.

For a business in Lengnau (AG), that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Aargau.

Frequently asked questions

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 Lengnau (AG): federal law applies.

When must a business register for VAT?

As soon as its worldwide annual turnover reaches CHF 100,000 (CHF 250,000 for non-profit sports or cultural associations). Below that, voluntary registration remains possible and often makes sense to reclaim input VAT on investments. The threshold is federal: it applies in Lengnau (AG) as everywhere in Switzerland.

Which documents should be prepared for the year-end closing?

Bank and cash statements at the closing date, the inventory of stock and work in progress, final AHV/LPP/accident settlements, contracts signed or amended during the year, invoices straddling two years and the detail of accruals. With an up-to-date document archive, most of it is already there. The list is identical in Lengnau (AG): the CO dictates it, not the commune.

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 Lengnau (AG) can therefore archive fully digitally.

Also worth reading

In neighbouring municipalities

Switch to accounting that keeps itself up to date

MyFiducia.ai automates tax advisory for businesses in Lengnau (AG): AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.

The application is operated in French.

    Tax advisory online in Lengnau (AG) | MyFiducia.ai