
VAT registration for engineering firms in Mellikon: what every SME should know
Delegate, digitalise or do it all yourself? Around VAT registration in Mellikon, every SME draws its own line. The reference points below — federal law, cantonal practice and lessons from the field — help you place the cursor well.
The Swiss legal frame for VAT registration
For an owner in Mellikon, 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.
Outsource VAT registration or keep it in-house?
The scope goes down in writing: who enters data, who approves payments, who answers the tax office, who keeps the originals. Every “we'll see” at the start becomes a December misunderstanding — in Mellikon as elsewhere.
For VAT registration, the internal-external duo works when both sides see the same file: same entries, same documents, same deadlines. Misunderstandings are born from parallel copies.
Swiss VAT: rates, threshold and filings
The most frequent VAT mistakes are well known: the wrong rate among 8.1%, 2.6% and 3.8%, forgotten self-supplies, and a rushed annual reconciliation. Corrections are due at the latest in the return for the period containing the 180th day after the year-end — the earlier you correct, the less default interest runs.
For an SME in Mellikon, electronic filing of VAT returns has been mandatory since 1 January 2025; the tax administration's online portal is also where extensions are requested and past periods consulted. Combined with accounts that prepare the return automatically, VAT registration stops being a quarterly chore.

Digitalising VAT registration: what actually works
Security is part of digitalisation: named access, tested backups, encryption of sensitive data. A digital accounting file is protected like a safe — because it is one.
An SME in Mellikon that digitalises gains owner time first: less filing, fewer “where is that receipt?” questions, more attention to the trade — that is the real return of VAT registration.
Mellikon: what changes, what does not
Working with a fiduciary from Mellikon no longer depends on geography: the documents of a business in Mellikon are shared online, while the canton Aargau keeps its own deadlines for the tax return.
Federal deadlines do not move in Mellikon: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 5465 changes nothing about those rules, only the sender's address.
Frequently asked questions
What are the legal obligations for VAT registration 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 Mellikon: federal law applies.
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 Mellikon: the CO dictates it, not the commune.
Which social contributions does a Swiss employer pay?
AHV/IV/APG: 5.3% employer share (the same is withheld from the employee); unemployment insurance: 1.1% each up to CHF 148,200 a year; occupational pension (LPP) by age and plan (employer at least 50%); occupational accident insurance paid by the employer; family allowances by canton. For an employer in Mellikon, family allowances follow the canton's rates.
Can VAT registration 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 VAT registration.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates VAT registration for businesses in Mellikon: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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