Side Business While Employed in Germany: 2026 Guide

More money on the side without giving up a stable job — the side business is by far the most common path into self-employment for employees in Germany. Set up correctly, you save tax, stay a Kleinunternehmer, and your employer has no veto. Set up wrong, your first tax assessment costs you €6,000 in back-tax. This guide covers both.

In short: Side businesses alongside employment are legal in Germany and mostly possible without employer approval (but notification is required). Gewerbe (trade) needs a €20-60 registration; freelancers only file a Finanzamt questionnaire. With revenue under €25,000 → Kleinunternehmer (no VAT). Side income is added to your salary and taxed at your marginal rate (30-42%). Rule: put aside 30% of every side-business invoice.

The five-step flow

1. Check your employment contract — is there a side-activity clause?
2. Notify your employer (or obtain written consent, depending on the clause)
3. Freelancer or Gewerbe? → trade registration or straight to the Finanzamt
4. Fragebogen zur steuerlichen Erfassung (tax-registration questionnaire) with the Finanzamt on ELSTER, within 1 month
5. Choose Kleinunternehmer status (in 95% of cases yes)

All five in place, and you’re set to take the first order.

Steps 1-2: handling your employer

Typical clauses

Practically every German employment contract contains one of:

• Notification obligation (most common): you must declare the activity. The employer can only refuse for good cause.
• Consent obligation: you need active written consent before starting.
• Non-compete: you can’t work in direct competition. Often applies even without a clause via loyalty duty.
• No clause at all: you’re freer, but general duty of loyalty still applies.

Notification template

A short, factual message works almost always:

Dear [manager],

I am notifying you of an intended side activity: - Type of activity: [e.g. freelance software development] - Planned scope: max. 10 hours per week, always outside my working hours - Clients: private or business clients unrelated to [company]

The activity does not impair my main job and does not compete with the company.

Best regards …

When the employer can refuse

Only if:

• direct competition with the employer’s business
• combined hours exceed 48/week (ArbZG labour law)
• your main performance noticeably suffers

Everything else they must tolerate.

Step 3: Gewerbe or freelancer?

This is the fork in the road — and the most common source of confusion.

Freelancer (§18 EStG) — no Gewerbe

If your side activity falls into a catalog profession or similar category:

• Software developer, programmer
• Writer, journalist, author
• Graphic designer, photographer (with genuine creative input)
• Consultant (management, IT, tax)
• Lecturer, coach with a pedagogical qualification
• Translator, interpreter
• Architect, engineer
• Medical professions (doctor, therapist, Heilpraktiker)

What you do:

• No trade office, no IHK, no trade tax (Gewerbesteuer)
• Just the Fragebogen zur steuerlichen Erfassung with the Finanzamt on ELSTER — within 1 month of your first order
• Request a tax number (Steuernummer) from the Finanzamt

Gewerbe (§15 EStG)

Everything else: retail (including Etsy, eBay shop), gastronomy, craft work, services without catalog membership, coaching without qualification, content creation/influencer work, brokering.

What you do:

• Gewerbeanmeldung (trade registration) at your city’s Gewerbeamt (€20-60 one-time)
• IHK or HWK membership automatic — under the low-revenue threshold = €0 in contributions
• Trade tax from €24,500 profit/year (below that: €0)
• Additionally, the Fragebogen zur steuerlichen Erfassung with the Finanzamt

In doubt

The freelancer-vs-Gewerbe borderline is often tricky — especially for coaching, consulting, hybrid activities. When unsure, consult a Steuerberater or submit to the Finanzamt and let them classify. Misclassification later is painful: retroactive Gewerbesteuer or forced restructuring.

Steps 4-5: questionnaire + Kleinunternehmer

Fragebogen zur steuerlichen Erfassung

Mandatory within 1 month of your first order. Online on ELSTER:

• Personal data + Steuer-ID
• Activity description
• Expected annual revenue + annual profit (estimate — can be off, but realistic)
• Bank account for VAT payments (if applicable)
• Choice: Kleinunternehmer under §19 UStG, or regular VAT

Kleinunternehmer (§19 UStG) — almost always yes

You qualify as Kleinunternehmer if your revenue:

• Last year ≤ €25,000 (€0 if you’re starting fresh)
• This year expected ≤ €100,000

What this means:

• Invoices without VAT — with the note “Gemäß §19 UStG wird keine Umsatzsteuer berechnet.”
• No monthly VAT advance returns
• No annual VAT return (or only simplified)
• Most side businesses under €25,000 revenue → always choose Kleinunternehmer

Exception: you have business clients who can reclaim VAT and you buy a lot of materials. Then regular VAT can be more lucrative (you claim your input tax). Rare for side business.

Tax maths: how much to set aside

This is where new side-business owners often get stung. Your side-business profit is added to your salary and taxed at your personal marginal rate.

Worked example

Jana, employed marketing manager, salary €70,000 gross. Side business 2026: €8,000 profit (after business expenses).

Without the side business:

• Income tax on €70,000 ≈ €19,000
• Wage tax withheld at source → no back payment

With the side business:

• Income tax on €78,000 ≈ €22,400
• Wage tax already withheld on €70,000 → ~€19,000
• Back payment: ~€3,400
• Effective tax rate on the side income: ~42%

Rule of thumb: Set aside 30% of every side-business receipt (profit, not revenue) into a separate savings account. The back-tax won’t surprise you.

From year two: prepayments

After your first tax assessment, the Finanzamt sets quarterly income-tax prepayments (due March 10, June 10, Sept 10, Dec 10). This smooths the cashflow shock but doesn’t change your total tax burden.

Tax-return appendices

Three additional forms on top of your normal employee return:

• Anlage S (self-employment income) — if you’re a freelancer
• Anlage G (trade income) — if you’re a Gewerbe
• Anlage EÜR (income-surplus calculation) — required for both, shows revenue and expenses
• Anlage N — your normal salary (as before)

What’s deductible

As a side-business owner you have your own “bucket” of business expenses — separate from your employee Werbungskosten.

• Work equipment (laptop, software, tools)
• Home office allowance pro-rated
• Internet and phone pro-rated
• Client trips (€0.30/€0.38 per km or actual costs)
• Office supplies, books, training
• Domain, hosting, online tools, bookkeeping software
• Advertising, marketing, website costs
• Portion of health insurance (if the side business triggers extra premiums)

See also: Freelancer deductions in Germany and VAT for freelancers.

Health insurance: when it gets tricky

As long as you stay primarily employed, your health insurance runs through your employer. The side business is insurance-free.

But if your side-business profit grows too large, your insurer may reclassify you as primarily self-employed — with significantly higher premiums. Typical signals:

• Side-business profit persistently > main salary
• Time spent on side business > 30 h/week
• Side business becomes your “economic focus”

Rule of thumb: keep side-business profit below 50% of your main salary to stay under the radar. Above that, have a proactive chat with your health insurer.

Common mistakes

1. Started without notifying the employer. In the worst case, that’s grounds for immediate termination. Always notify.
2. Wrong classification: registered a Gewerbe for a freelance activity — paying unnecessary IHK or trade tax.
3. No reserves built. First tax bill = €4,000. Account empty.
4. Forgot the questionnaire. First invoice without a tax number = client pulls out.
5. Missed the Kleinunternehmer option — unnecessary VAT bookkeeping and monthly filings.
6. Everything in Excel. With >10 invoices per year, accounting software (from €10/month) pays off — and is itself deductible.

Related topics

• Kleinunternehmer threshold 2026 — when your side business grows
• Freelancer deductions — the EÜR handbook
• Avoiding fake self-employment — critical when the side business is concentrated on one client

How Restio helps

A side business is a textbook Restio use case — many small decisions, tight deadlines, a mixed tax picture of salary + self-employment:

• Onboarding check — answer 8 questions, Restio tells you whether you’re Gewerbe or freelancer, whether Kleinunternehmer fits, and which forms you need. No €300 initial consultation required.
• Reserve tracker — log every invoice, Restio calculates your tax liability live and flags how much to put aside.
• Kleinunternehmer guardian — an alert before you blow the €25,000 threshold, with a timeline and action plan.
• Receipt scanner — photo of a purchase, Restio categorises it as “private” or “side business” and keeps a clean expense ledger.
• Instant answers — “Can I deduct my laptop as an employee?”, “How do I enter this on Anlage S?”, “Do I have to file VAT if I’m Kleinunternehmer?” — in English or German.

A side business is the best form of freedom German tax law allows: stable income plus additional upside, with clear rules. Those who know the rules save thousands. Those who ignore them, pay them.