If you start a side hustle in Germany (like publishing books or affiliate marketing) while working a full-time job, your health insurance provider ( e.g. AOK) will send you a form called “Prüfung der Krankenversicherungspflicht”.

📅 Real-Life App Timeline: What to Expect

They want to confirm that your regular job is still your main focus so you do not have to pay extra health insurance fees on your side income.

Using the official Meine AOK App makes communication incredibly fast, but you need to know the workflow:

Friday: I sent a message to AOK through the app’s text/chat function and attached the 2nd page of the Business Registration (Gewerbeanmeldung).

Monday (Today): AOK replied back through the app and I got a notification of a new message through email. Because a simple document upload isn’t enough for their legal check, they officially requested the full questionnaire form to be filled out.

Here was the email notification I received prompting me to check the AOK App:

Monday (Same Day): I downloaded the form, filled out the required entries completely, attached all 4 necessary supporting documents directly through the app portal, and submitted everything in one message.

Here was the message I sent them including the attachments:

Filling out their form is quite tricky. I find their one page questionnaire can be confusing if not read properly. Below are hepful tips on how to get started:

how to answer the form properly

📋 Step 1: Your Primary Job Details (Angaben als Arbeitnehmer)

In this section, prove that your main job takes up most of your time and provides your main income.

Wöchentliche Arbeitszeit: Enter your official weekly contract hours (e.g., 38.5 or 40 hours).

Durchschnittliches monatliches Bruttoarbeitsentgelt: Write your exact monthly gross salary (Gesamtbrutto) from your latest payslip.

Zeitraum der Beschäftigung: Enter your job’s start date. If your contract has no end date, write “unbefristet” (permanent) in the “bis” (until) field.

💼 Step 2: Your Side-Hustle Details (Angaben zur Selbstständigkeit)

Keep these numbers aligned with what you told the tax office (Finanzamt).

Meine Angaben zur Selbstständigkeit ab dem: The official start date of your business.

Ich bin selbstständig tätig als: Your business title (e.g., “Buchautorin & Online-/Affiliate-Marketing”).

Durchschnittliches monatliches Einkommen: Your estimated monthly net profit (revenue minus expenses).

Tip: If you gave the tax office a yearly estimate, divide that number by 12. If your yearly profit is €300, write €25.

Wöchentliche Arbeitszeit als Selbstständiger: The hours you spend on your side hustle weekly. Keep this low (e.g., 5 or 10 hours). It must be significantly lower than your main job.

Gewerbeum-/abmeldung: If you registered a trade for marketing, check “ja, zum” and fill in your start date.

📎 Step 3: The 4 Required Attachments

Do not send the form alone! When replying in the app, you must upload these four items together:

The Completed Form: Signed and dated at the bottom.

Here is a sample form:

Your Payslip: A photocopy or digital PDF of a recent monthly payslip to prove your main income.

Here’s a cropped copy of mine:

Your Business Registration: A copy of your official Gewerbeanmeldung (make sure to upload all pages!). Note: If the app says “Seiten werden zusammengefügt”, don’t panic! It just means it is combining your pages into one clean document.

Here was mine:

and A Profit Explanation Note (Gewinnschätzung): A short letter explaining your low starting numbers, since you don’t have an official tax paper (Steuerbescheid) yet.

📝 Free German Letter Template for the Profit Note

Copy, paste, and fill out this text on a blank page to upload as your official income estimate:

Erklärung zur Gewinnschätzung für [Your Name]

Sehr geehrte Damen und Herren,

hiermit bestätige ich, dass ich beim Finanzamt für das Jahr der Betriebseröffnung einen erwarteten Gewinn von [e.g., 150,- €] aus gewerblicher Tätigkeit und [e.g., 150,- €] aus selbstständiger Arbeit angegeben habe. Dies entspricht einem kombinierten Jahresgewinn von insgesamt [e.g., 300,- €] bzw. einem durchschnittlichen monatlichen Einkommen von [e.g., 25,- €].

Für das Folgejahr wird ein kombinierter Gesamtgewinn von [e.g., 500,- €] erwartet.

Mit freundlichen Grüßen

[Your Signature]

Here was mine:

💡 The Golden Rule for Side-Hustlers

As long as your side hustle takes up less than 20 hours a week and your monthly profit stays under the legal social security threshold (around €603/month), your side hustle remains 100% contribution-free (beitragsfrei). Your main job continues to pay for your full health insurance!

⚠️ Why You Must Inform your Health Insurance Provider (The Risks of Staying Silent)

Some people think, “My side business makes almost no money, so I don’t need to tell my health insurance.” This is a massive mistake in Germany.

Here is why keeping them informed protects you:

The Tax Office Loophole: When you register your business via ELSTER, the tax office (Finanzamt) automatically shares data with other government bodies [📈]. Eventually, AOK will find out about your side hustle anyway.

The Risk of Back-Payments (Beitragsnachzahlung): If AOK discovers your business months or years late, they will assume by default that you were working full-time on it. They can retroactively change your status to “primarily self-employed” and force you to pay thousands of Euros in back-premiums for the missing months.

It Costs You Nothing to Be Honest: As long as your side hustle stays small, submitting this form changes absolutely nothing about your current insurance. Your monthly premium remains €0 extra, but your file is legally protected and compliant. It gives you 100% peace of mind.

🚀 Conclusion: Compliance Drives Success

At the end of the day, keeping your health insurance company informed isn’t just about avoiding a bureaucratic headache—it is about setting your business up for long-term growth. When your paperwork is 100% compliant, you eliminate financial stress, unexpected back-payments, and legal risks. Ensuring your legal foundation is secure gives you the ultimate peace of mind to focus entirely on what matters most: growing your audience, publishing your books, scaling your marketing channels, and watching your side business progress safely into a thriving success.